Patent Publication Number: US-2023141581-A1

Title: Method of adjusting size of exposed area of flexible display and electronic device performing the method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a national stage application of International Application No. PCT/KR2022/014145 designating the United States, filed on Sep. 22, 2022, in the Korean Intellectual Property Receiving Office and claiming priority to Korean Patent Application No. 10-2021-0153726, filed on Nov. 10, 2021, in the Korean Intellectual Property Office, and Korean Patent Application No. 10-2022-0010943, filed on Jan. 25, 2022, in the Korean Intellectual Property Office, the disclosures of which are all hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     1. Field Various example embodiments relate to technology for adjusting the size of an exposed area of a flexible display of an electronic device. 
     2. Description of Related Art 
     The development of display technology introduces various expandable displays. For example, such an expandable display may be implemented through a flexible display. The flexible display may be flexible as it uses a plastic film instead of glass. The flexible display is not only thin and light, but also resistant to shock and bendable so that the flexible display may be manufactured in various shapes. Such a flexible display may be used in an industrial field in which a glass substrate-based display has been restrictively or hardly used. 
     SUMMARY 
     A degree of expanding/reducing an area exposed externally on a flexible display may vary depending on the size of each stage. In addition, when a user uses an activated electronic device including a flexible display, there may be two cases: a) where the user intends to use the electronic device as it is, without expanding/reducing the size of an exposed area of the flexible display and b) where the user intends to use the electronic device with the flexible display expanded/reduced according to the purpose of use of the electronic device. When the user intends to expand/reduce the size of the exposed area of the flexible display according to the purpose of use of the electronic device, the user may desire to quickly adjust the size of the exposed area of the flexible display when the electronic device is activated. 
     An example embodiment may provide an electronic device that outputs an affordance for adjusting a size of an exposed area of a flexible display. 
     According to an example embodiment, an affordance may include, but not be limited to, a graphic object, a user interface, an icon, a text object, a window, audio output through a speaker, or vibration through a haptic module, which are shown on a display to induce the user&#39;s action (e.g., control of an electronic device or selection for options visually or audibly output through the electronic device). 
     However, the technical aspects are not limited to the aforementioned aspects, and other technical aspects may be present. 
     According to an example embodiment, an electronic device may include a driving module comprising a motor and/or circuitry, a flexible display having a variable size of an exposed area viewable externally on a side (e.g., one side) as at least a portion of the flexible display is drawn out from an inside of the electronic device by driving of the driving module, at least one memory configured to store executable instructions, and a processor configured to be operatively connected, directly or indirectly, to the driving module, the flexible display, and the at least one memory and control the electronic device. The processor may be configured by executing the instructions to identify a first size of the exposed area, output, on at least a portion of the exposed area, an affordance including at least one selectable user interface (UI) element configured to change a size of the exposed area based on the identified first size, and when a UI element is selected from among the at least one UI element, control the driving module to change the size of the exposed area from the first size to a second size substantially corresponding to a selected UI element. 
     According to an example embodiment, a method performed by an electronic may include outputting, on at least a portion of an exposed area, an affordance for adjust a size of the exposed area when a flexible display has a variable size of an exposed area viewed externally on one side as at least a portion of the flexible display is drawn out from an inside of the electronic device and the flexible display is activated, identifying a target size on the exposed area, based on an input to the affordance, controlling the driving module configured to move the flexible display to have the size of the exposed area correspond to the target size. 
     According to an example embodiment, an electronic device may include a flexible display having a variable size of an exposed area viewed externally on one side as at least a portion of the flexible display is drawn out from an inside of the electronic device, at least one memory configured to store executable instructions, and at least one processor configured to control the electronic device. The processor may be configured to output, on at least a portion of an exposed area, an affordance for adjusting a size of the exposed area when an input of deactivating the flexible display is received, receive information on a second target size of a second target based on an additional affordance, control the flexible display to have the size of the exposed area correspond to the second target size, and deactivate the flexible display. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the present disclosure will be more apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    is a block diagram illustrating an electronic device in a network environment, according to an example embodiment; 
         FIG.  2    is a block diagram of a display module according to an example embodiment; 
         FIGS.  3 A and  3 B  are front perspective views illustrating a reduction state and an expansion state of an electronic device including a flexible display according to various example embodiments; 
         FIG.  4 A and  4 B  are rear perspective views illustrating a reduction state and an expansion state of an electronic device including a flexible display according to various example embodiments; 
         FIG.  5    illustrates an affordance including a plurality of user interface (UI) elements, according to an example embodiment; 
         FIG.  6    is a flowchart of a method of adjusting the size of an exposed area of a flexible display, according to an example embodiment; 
         FIG.  7    is a flowchart of a method of outputting an affordance to include a plurality of UI elements, according to an example embodiment; 
         FIGS.  8 A,  8 B, and  8 C  illustrate a plurality of affordances that vary according to a current size of an exposed area, according to various example embodiments; 
         FIG.  9    is a flowchart of a method of outputting an affordance generated based on a previous size of an exposed area before a flexible display is deactivated, according to an example embodiment; 
         FIG.  10    illustrates an affordance including an additional UI element generated based on a previous size of an exposed area before a flexible display is deactivated, according to an example embodiment; 
         FIG.  11    is a flowchart of a method of outputting an affordance generated based on an application executed in the foreground, according to an example embodiment; 
         FIG.  12    illustrates an affordance including an additional UI element generated based on an application executed in the foreground, according to an example embodiment; 
         FIG.  13    is a flowchart of a method of changing a color of a target UI element, based on the remaining capacity of a battery, according to an example embodiment; 
         FIG.  14    is a flowchart of a method of outputting an affordance generated based on target applications, controlling a flexible display based on an affordance selection input, and executing an application, according to an example embodiment; 
         FIG.  15    illustrates an affordance including a plurality of application icons generated based on target applications, according to an example embodiment; 
         FIG.  16    illustrates a method in which an application icon selected by a user is dragged to a preset target area in an exposed area, according to an example embodiment; 
         FIG.  17    is a flowchart of a method of outputting an affordance based on a coordinate of a reference display determined based on a user&#39;s touch input, according to an example embodiment; 
         FIGS.  18 A and  18 B  illustrate a method of receiving, from a user, a drag input of an affordance output based on a coordinate of a reference display, according to an example embodiment. 
         FIGS.  19 A,  19 B, and  19 C  illustrate a plurality of affordances according to various example embodiments; 
         FIG.  20    is a flowchart of a method of outputting an additional affordance when an input of deactivating a flexible display is received and controlling a flexible display based on an additional affordance, according to an example embodiment; and 
         FIG.  21    illustrates a method of outputting an additional affordance when an input of deactivating a flexible display is received and controlling a flexible display based on an additional affordance, according to an example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, various embodiments of the present disclosure will be described with reference to the accompanying drawings. However, this is not intended to limit the present disclosure to specific embodiments, and it should be understood that various modifications, equivalents, and/or alternatives of the embodiments of the present disclosure are included. 
       FIG.  1    is a block diagram illustrating an electronic device in a network environment, according to an example embodiment. 
       FIG.  1    is a block diagram illustrating an electronic device  101  in a network environment  100  according to embodiments. Referring to  FIG.  1   , the electronic device  101  in the network environment  100  may communicate with an electronic device  102  via a first network  198  (e.g., a short-range wireless communication network), or communicate with at least one of an electronic device  104  or a server  108  via a second network  199  (e.g., a long-range wireless communication network). According to an example embodiment, the electronic device  101  may communicate with the electronic device  104  via the server  108 . According to an example embodiment, the electronic device  101  may include a processor  120 , a memory  130 , an input module  150 , a sound output module  155 , a display module  160 , an audio module  170 , and a sensor module  176 , an interface  177 , a connecting terminal  178 , a haptic module  179 , a camera module  180 , a power management module  188 , a battery  189 , a communication module  190 , a subscriber identification module (SIM)  196 , or an antenna module  197 . In some embodiments, at least one (e.g., the connecting terminal  178 ) of the above components may be omitted from the electronic device  101 , or one or more other components may be added in the electronic device  101 . In some embodiments, some (e.g., the sensor module  176 , the camera module  180 , or the antenna module  197 ) of the components may be integrated as a single component (e.g., the display module  160 ). 
     The processor  120  may execute, for example, software (e.g., a program  140 ) to control at least one other component (e.g., a hardware or software component) of the electronic device  101  connected, directly or indirectly, to the processor  120 , and may perform various data processing or computation. according to an example embodiment, as at least a part of data processing or computation, the processor  120  may store a command or data received from another component (e.g., the sensor module  176  or the communication module  190 ) in a volatile memory  132 , process the command or the data stored in the volatile memory  132 , and store resulting data in a non-volatile memory  134  (which may include internal memory  136  and/or external memory  138 ). According to an example embodiment, the processor  120  may include a main processor  121  (e.g., a central processing unit (CPU) or an application processor (AP)) or an auxiliary processor  123  (e.g., a graphics processing unit (GPU), a neural processing unit (NPU), an image signal processor (ISP), a sensor hub processor, or a communication processor (CP)) that is operable independently of, or in conjoint with the main processor  121 . For example, when the electronic device  101  includes the main processor  121  and the auxiliary processor  123 , the auxiliary processor  123  may be adapted to consume less power than the main processor  121  or to be specific to a specified function. The auxiliary processor  123  may be implemented separately from the main processor  121  or as a part of the main processor  121 . 
     The auxiliary processor  123  may control at least some of functions or states related to at least one (e.g., the display module  160 , the sensor module  176 , or the communication module  190 ) of the components of the electronic device  101 , instead of the main processor  121  while the main processor  121  is in an inactive (e.g., sleep) state or along with the main processor  121  while the main processor  121  is an active state (e.g., executing an application). According to an example embodiment, the auxiliary processor  123  (e.g., an ISP or a CP) may be implemented as a portion of another component (e.g., the camera module  180  or the communication module  190 ) that is functionally related to the auxiliary processor  123 . according to an example embodiment, the auxiliary processor  123  (e.g., an NPU) may include a hardware structure specified for artificial intelligence (AI) model processing. An AI model may be generated by machine learning. Such learning may be performed by, for example, the electronic device  101  in which artificial intelligence is performed, or performed via a separate server (e.g., the server  108 ). Learning algorithms may include, but are not limited to, for example, supervised learning, unsupervised learning, semi-supervised learning, or reinforcement learning. The AI model may include a plurality of artificial neural network layers. An artificial neural network may include, for example, a deep neural network (DNN), a convolutional neural network (CNN), a recurrent neural network (RNN), a restricted Boltzmann machine (RBM), a deep belief network (DBN), and a bidirectional recurrent deep neural network (BRDNN), a deep Q-network, or a combination of two or more thereof, but is not limited thereto. The AI model may additionally or alternatively include a software structure other than the hardware structure. 
     The memory  130  may store various data used by at least one component (e.g., the processor  120  or the sensor module  176 ) of the electronic device  101 . The various data may include, for example, software (e.g., the program  140 ) and input data or output data for a command related thereto. The memory  130  may include the volatile memory  132  or the non-volatile memory  134 . 
     The program  140  may be stored as software in the memory  130 , and may include, for example, an operating system (OS)  142 , middleware  144 , or an application  146 . 
     The input module  150  may receive a command or data to be used by another component (e.g., the processor  120 ) of the electronic device  101 , from the outside (e.g., a user) of the electronic device  101 . The input module  150  may include, for example, a microphone, a mouse, a keyboard, a key (e.g., a button), or a digital pen (e.g., a stylus pen). 
     The sound output module  155  may output a sound signal to the outside of the electronic device  101 . The sound output module  155  may include, for example, a speaker or a receiver. The speaker may be used for general purposes, such as playing multimedia or playing record. The receiver may be used to receive an incoming call. According to an example embodiment, the receiver may be implemented separately from the speaker or as a part of the speaker. 
     The display module  160  may visually provide information to the outside (e.g., a user) of the electronic device  101 . The display module  160  may include, for example, a control circuit for controlling a display, a hologram device, or a projector and control circuitry to control a corresponding one of the display, the hologram device, and the projector. According to an example embodiment, the display module  160  may include a touch sensor adapted to sense a touch, or a pressure sensor adapted to measure an intensity of a force incurred by the touch. 
     The audio module  170  may convert a sound into an electric signal or vice versa. According to an example embodiment, the audio module  170  may obtain the sound via the input module  150  or output the sound via the sound output module  155  or an external electronic device (e.g., an electronic device  102  such as a speaker or a headphone) directly or wirelessly connected to the electronic device  101 . 
     The sensor module  176  may detect an operational state (e.g., power or temperature) of the electronic device  101  or an environmental state (e.g., a state of a user) external to the electronic device  101 , and generate an electric signal or data value corresponding to the detected state. According to an example embodiment, the sensor module  176  may include, for example, a gesture sensor, a gyro sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an infrared (IR) sensor, a biometric sensor, a temperature sensor, a humidity sensor, or an illuminance sensor. 
     The interface  177  may support one or more specified protocols to be used for the electronic device  101  to be coupled with the external electronic device (e.g., the electronic device  102 ) directly (e.g., wiredly) or wirelessly. According to an example embodiment, the interface  177  may include, for example, a high-definition multimedia interface (HDMI), a universal serial bus (USB) interface, a secure digital (SD) card interface, or an audio interface. The connecting terminal  178  may include a connector via which the electronic device  101  may be physically connected to an external electronic device (e.g., the electronic device  102 ). According to an example embodiment, the connecting terminal  178  may include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (e.g., a headphone connector). 
     The haptic module  179  may convert an electric signal into a mechanical stimulus (e.g., a vibration or a movement) or an electrical stimulus which may be recognized by a user via his or her tactile sensation or kinesthetic sensation. According to an example embodiment, the haptic module  179  may include, for example, a motor, a piezoelectric element, or an electric stimulator. 
     The camera module  180  may capture a still image and moving images. According to an example embodiment, the camera module  180  may include one or more lenses, image sensors, ISPs, or flashes. 
     The power management module  188  may manage power supplied to the electronic device  101 . According to an example embodiment, the power management module  188  may be implemented as, for example, at least a part of a power management integrated circuit (PMIC). 
     The battery  189  may supply power to at least one component of the electronic device  101 . According to an example embodiment, the battery  189  may include, for example, a primary cell which is not rechargeable, a secondary cell which is rechargeable, or a fuel cell. 
     The communication module  190  may support establishing a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device  101  and the external electronic device (e.g., the electronic device  102 , the electronic device  104 , or the server  108 ) and performing communication via the established communication channel. The communication module  190  may include one or more communication processors that are operable independently of the processor  120  (e.g., an AP) and that support a direct (e.g., wired) communication or a wireless communication. According to an example embodiment, the communication module  190  may include a wireless communication module  192  (e.g., a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module  194  (e.g., a local area network (LAN) communication module, or a power line communication (PLC) module). A corresponding one of these communication modules may communicate with the external electronic device  104  via the first network  198  (e.g., a short-range communication network, such as Bluetooth™, wireless-fidelity (Wi-Fi) direct, or infrared data association (IrDA)) or the second network  199  (e.g., a long-range communication network, such as a legacy cellular network, a 5G network, a next-generation communication network, the Internet, or a computer network (e.g., a LAN or a wide area network (WAN))). These various types of communication modules may be implemented as a single component (e.g., a single chip), or may be implemented as multiple components (e.g., multiple chips) separate from each other. The wireless communication module  192  may identify and authenticate the electronic device  101  in a communication network, such as the first network  198  or the second network  199 , using subscriber information (e.g., international mobile subscriber identity (IMSI)) stored in the SIM  196 . 
     The wireless communication module  192  may support a 5G network after a 4G network, and next-generation communication technology, e.g., new radio (NR) access technology. The NR access technology may support enhanced mobile broadband (eMBB), massive machine type communications (mMTC), or ultra-reliable and low-latency communications (URLLC). The wireless communication module  192  may support a high-frequency band (e.g., a mmWave band) to achieve, e.g., a high data transmission rate. The wireless communication module  192  may support various technologies for securing performance on a high-frequency band, such as, e.g., beamforming, massive multiple-input and multiple-output (MIMO), full dimensional MIMO (FD-MIMO), an array antenna, analog beam-forming, or a large scale antenna. The wireless communication module  192  may support various requirements specified in the electronic device  101 , an external electronic device (e.g., the electronic device  104 ), or a network system (e.g., the second network  199 ). According to an example embodiment, the wireless communication module  192  may support a peak data rate (e.g., 20 Gbps or more) for implementing eMBB, loss coverage (e.g., 164 dB or less) for implementing mMTC, or U-plane latency (e.g., 0.5 ms or less for each of downlink (DL) and uplink (UL), or a round trip of 1 ms or less) for implementing URLLC. 
     The antenna module  197  may transmit or receive a signal or power to or from the outside (e.g., the external electronic device) of the electronic device  101 . According to an example embodiment, the antenna module  197  may include an antenna including a radiating element including a conductive material or a conductive pattern formed in or on a substrate (e.g., a printed circuit board (PCB)). According to an example embodiment, the antenna module  197  may include a plurality of antennas (e.g., array antennas). In such a case, at least one antenna appropriate for a communication scheme used in a communication network, such as the first network  198  or the second network  199 , may be selected by, for example, the communication module  190  from the plurality of antennas. The signal or the power may be transmitted or received between the communication module  190  and the external electronic device via the at least one selected antenna. According to an example embodiment, another component (e.g., a radio frequency integrated circuit (RFIC)) other than the radiating element may be additionally formed as a part of the antenna module  197 . 
     According to various embodiments, the antenna module  197  may form a mmWave antenna module. According to an example embodiment, the mmWave antenna module may include a PCB, an RFIC disposed on a first surface (e.g., a bottom surface) of the PCB or adjacent to the first surface and capable of supporting a designated a high-frequency band (e.g., the mmWave band), and a plurality of antennas (e.g., array antennas) disposed on a second surface (e.g., a top or a side surface) of the PCB, or adjacent to the second surface and capable of transmitting or receiving signals in the designated high-frequency band. 
     At least some of the above-described components may be coupled mutually and communicate signals (e.g., commands or data) therebetween via an inter-peripheral communication scheme (e.g., a bus, general purpose input and output (GPIO), serial peripheral interface (SPI), or mobile industry processor interface (MIPI)). 
     According to an example embodiment, commands or data may be transmitted or received between the electronic device  101  and the external electronic device  104  via the server  108  coupled with the second network  199 . Each of the external electronic devices  102  and  104  may be a device of the same type as or a different type from the electronic device  101 . according to an example embodiment, all or some of operations to be executed by the electronic device  101  may be executed at one or more external electronic devices (e.g., the external devices  102  and  104 , and the server  108 ). For example, if the electronic device  101  needs to perform a function or a service automatically, or in response to a request from a user or another device, the electronic device  101 , instead of, or in addition to, executing the function or the service, may request one or more external electronic devices to perform at least part of the function or the service. The one or more external electronic devices receiving the request may perform the at least part of the function or the service requested, or an additional function or an additional service related to the request, and may transfer an outcome of the performing to the electronic device  101 . The electronic device  101  may provide the outcome, with or without further processing of the outcome, as at least part of a reply to the request. To that end, a cloud computing, distributed computing, mobile edge computing (MEC), or client-server computing technology may be used, for example. The electronic device  101  may provide ultra low-latency services using, e.g., distributed computing or MEC. In an example embodiment, the external electronic device (e.g., the electronic device  104 ) may include an Internet-of-things (IoT) device. The server  108  may be an intelligent server using machine learning and/or a neural network. according to an example embodiment, the external electronic device  104  or the server  108  may be included in the second network  199 . The electronic device  101  may be applied to intelligent services (e.g., smart home, smart city, smart car, or healthcare) based on 5G communication technology or IoT-related technology. 
       FIG.  2    is a block diagram of a display module according to an example embodiment. 
     Referring to  FIG.  2   , a display module  160  described with reference to  FIG.  1    may include a display  210  and a display driver IC (DDI)  230  configured to control the display  210 . 
     The DDI  230  may include an interface module  231 , a memory  233  (e.g., a buffer memory), an image processing module  235 , or a mapping module  237 . The DDI  230  may receive, for example, image data or image information including an image control signal corresponding to a command for controlling the image data from other components of the electronic device  101  through the interface module  231 . According to an example embodiment, image information may be received by the processor  120  (e.g., the main processor  121  (e.g., an application processor) or the auxiliary processor  123  (e.g., a graphics processing device) operated independently from a function of the main processor  121 ). The DDI  230  may communicate with a touch circuit  250  or a sensor module  176  through the interface module  231 . Also, the DDI  230  may store at least some of the received image information in the memory  233 , for example, in frame units. 
     The image processing module  235  may, for example, pre-process or post-process (e.g., adjusting resolution, brightness, or size) at least some of the image data based on at least a characteristic of the image data or a characteristic of the display  210 . 
     The mapping module  237  may generate a voltage value or a current value corresponding to the image data pre-processed or post-processed by the image processing module  235 . According to an example embodiment, generating the voltage value or the current value may be, for example, performed based on at least some of a property of pixels of the display  210  (e.g., the arrangement of pixels (an RGB-stripe structure or pentile structure), or the size of each sub-pixel). At least some pixels of the display  210  may, for example, be driven at least partially based on the voltage value or the current value, so that visual information (e.g., a text, image, or icon) corresponding to the image data may be presented on the display  210 . 
     According to an example embodiment, the display module  160  may further include the touch circuit  250 . The touch circuit  250  may include a touch sensor  251  and a touch sensor IC  253  configured to control the touch sensor  251 . The touch sensor IC  253  may, for example, control the touch sensor  251  to sense a touch input or a hovering input of a specific position of the display  210 . For example, the touch sensor IC  253  may measure a change in a signal for a specific position of the display  210  (e.g., a voltage, a light amount, resistance, or an electric charge amount) and thus sense a touch input or a hovering input. The touch sensor IC  253  may provide information on the sensed touch input or hovering input (e.g., a position, an area, a pressure, or time) to the processor  120 . According to an example embodiment, at least a part of the touch circuit  250  (e.g., the touch sensor IC  253 ) may be included as a part of the display driver IC  230  or the display  210 , or another component (e.g., the auxiliary processor  123 ) disposed outside the display module  160 . 
     According to an example embodiment, the display module  160  may further include at least one sensor (e.g., a fingerprint sensor, an iris sensor, a pressure sensor, or an illuminance sensor) of the sensor module  176 , or a control circuit for the at least one sensor. In this case, the at least one sensor or the control circuit for the at least one sensor may be embedded in a part of the display module  160  (e.g., the display  210  or the DDI  230 ) or a part of the touch circuit  250 . For example, when the sensor module  176  embedded in the display module  160  includes a biometric sensor (e.g., a fingerprint sensor), the biometric sensor may acquire biometric information related to a touch input (e.g., a fingerprint image) through a partial area of the display  210 . For example, when the sensor module  176  embedded in the display module  160  includes a pressure sensor, the pressure sensor may acquire pressure information related to a touch input on a part or the entire area of the display  210 . According to an example embodiment, the touch sensor  251  or the sensor module  176  may be disposed between pixels of a pixel layer of the display  210  or above or below the pixel layer. 
       FIGS.  3 A and  3 B  are front perspective views illustrating a reduction state and an expansion state of an electronic device including a flexible display according to various embodiments. 
       FIGS.  4 A and  4 B  are rear perspective views illustrating a reduction state and an expansion state of an electronic device including a flexible display according to various embodiments. 
     An electronic device  300  of  FIG.  3 A  may be similar to the electronic device  101  of  FIG.  1   , at least partially, or may further include other components than those of the electronic device  101  of  FIG.  1   . 
     Referring to  FIGS.  3 A to  4 B , the electronic device  300  may include a first housing  310  and a second housing  320  at least partially and movably connected, directly or indirectly, to the first housing  310 . According to an example embodiment, the first housing  310  may include a first plate  311  and a first side frame  312  that extends in a substantially vertical direction (e.g., the z-axis direction) along an edge of the first plate  311 . According to an example embodiment, the first side frame  312  may include a first side surface  3121 , a second side surface  3122  extending from one end of the first side surface  3121 , and a third side surface  3123  extending from the other end of the first side surface  3121 . According to an example embodiment, the first housing  310  may include a first space that is at least partially closed from the outside by the first plate  311  and the first side frame  312 . 
     According to various embodiments, the second housing  320  may include a second plate  321  and a second side frame  322  that extends in a substantially vertical direction (e.g., the z-axis direction) along an edge of the second plate  321 . According to an example embodiment, the second side frame  322  may include a fourth side surface  3221  facing away from the first side surface  3121 , a fifth side surface  3222  extending from one end of the fourth side surface  3221  and at least partially coupled to the second side surface  3122 , and a sixth side surface  3223  extending from the other end of the fourth side surface  3221  and at least partially coupled to the third side surface  3123 . In an example embodiment, the fourth side surface  3221  may extend from a structure other than the second plate  321  and may also be coupled to the second plate  321 . According to an example embodiment, the second housing  320  may include a second space that is at least partially closed from the outside by the second plate  321  and the second side frame  322 . According to an example embodiment, the first plate  311  and the second plate  321  may be disposed to at least partially form the rear surface of the electronic device  300 . For example, the first plate  311 , the second plate  321 , the first side frame  312 , and the second side frame  322  may be formed of, for example, polymer, coated or colored glass, ceramic, metal (e.g., aluminum, stainless steel (STS), or magnesium), or a combination of two or more of the materials stated above. 
     According to various embodiments, the electronic device  300  may include a flexible display  330  disposed to be supported by the first housing  310  and the second housing  320 . According to an example embodiment, the flexible display  330  may include a flat portion supported by the second housing  320 , and a bendable portion extending from the flat portion and supported by the first housing  310 . According to an example embodiment, the bendable portion of the flexible display  330  may be disposed in the first space of the first housing  310  and not exposed to the outside when the electronic device  300  is reduced and may be exposed to the outside to extend from the flat portion while being supported by the first housing  310  when the electronic device  300  is expanded. Accordingly, the electronic device  300  may be a rollable-type electronic device in which a display screen of the flexible display  330  is expanded in response to an expansion operation according to movement of the first housing  310  from the second housing  320 . 
     According to various embodiments, in the electronic device  300 , the first housing  310  may be at least partially inserted into the second space of the second housing  320  and may be coupled to be movable in direction {circle around ( 1 )}. For example, in the reduced state, the electronic device  300  may be maintained in a state in which the first housing  310  and the second housing  320  are coupled such that a distance between the first side surface  3121  and the fourth side surface  3221  is a first distance d 1 . according to an example embodiment, in the expanded state, the electronic device  300  may be maintained in a state in which the first housing  310  protrudes from the second housing  320  to have a second interval distance d in which the first side surface  3121  protrudes from the fourth side surface  3221  by a predetermined distance d 2 . According to an example embodiment, the flexible display  330  may be supported by the first housing  310  and/or the second housing  320  such that both ends thereof have curved edges, in the expanded state. 
     According to various embodiments, the electronic device  300  may automatically transition between the expanded state and the reduced state by a driving unit (or a driving module) disposed in the first space and/or the second space. For example, the driving unit may include a motor. For example, a processor (e.g., the processor  120  of  FIG.  1   ) of the electronic device  300  may be configured to control an operation of the first housing  310  by using the driving unit when an event for a transition between the open state and the closed state of the electronic device  300  is detected. In an example embodiment, the first housing  310  may manually protrude from the second housing  320  through a user&#39;s control. In this example, the first housing  310  may protrude by a desired amount of protrusion by the user, and thus, a screen of the flexible display  330  may vary to have various display areas. Accordingly, the processor (e.g., the processor  120  of  FIG.  1   ) of the electronic device  300  may display an object in various ways in response to a display area corresponding to a predetermined amount of protrusion of the first housing  310  and may control execution of an application program. Each “processor” herein comprises processing circuitry. 
     According to various embodiments, the electronic device  300  may include at least one of an input device (e.g., the input module  150  of  FIG.  1   ) and sound output devices (e.g., the sound output module  155  of  FIG.  1   ), sensor modules (e.g., the sensor module  176  of  FIG.  1   ), camera modules (e.g., the camera module  180  of  FIG.  1   ), a connector port  308  (e.g., the connecting terminal  178  of  FIG.  1   ), a key input device (not shown), or an indicator (not shown). In an example embodiment, at least one of the components described above of the electronic device  300  may be omitted, or the electronic device  300  may further include other components. 
     According to an example embodiment, the input device may include a microphone  303 . In an example embodiment, the input device may include a plurality of microphones  303  arranged to sense a direction of sound. The sound output devices may include speakers  306  (including  306 ′) and  307 . The speakers  306  and  307  may include an external speaker  306  and a phone call receiver  307 . In an example embodiment, when an external speaker  306  is disposed in the first housing  310 , sound may be output through a speaker hole formed in the second housing  320  in the reduced state. According to an example embodiment, the microphone  303  or the connector port  308  may also be formed to have substantially the same configuration. In an example embodiment, the sound output devices may include a speaker (e.g., a piezo speaker) that operates without a separate speaker hole. 
     According to an example embodiment, the sensor modules may generate an electrical signal or a data value corresponding to an internal operating state of the electronic device  300  or an external environmental state. The sensor modules may include, for example, a first sensor module  304  (e.g., a proximity sensor or an illuminance sensor) disposed on the front surface of the second housing  320  and/or a second sensor module  317  (e.g., a heart rate monitoring (HRM) sensor) disposed on the rear surface of the second housing  320 . According to an example embodiment, the first sensor module  304  may be disposed below the flexible display  330  in the second housing  320 . According to an example embodiment, the first sensor module  304  may further include at least one of a proximity sensor, the illuminance sensor, a time of flight (ToF) sensor, an ultrasonic sensor, a fingerprint recognition sensor, a gesture sensor, a gyro sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a color sensor, an IR sensor, a biometric sensor, a temperature sensor, or a humidity sensor. 
     According to an example embodiment, the camera devices may include a first camera device  305  disposed on the front surface of the second housing  320  of the electronic device  300 . And a second camera  316  disposed on the rear surface of the second housing  320 . According to an example embodiment, the electronic device  300  may include a flash  318  near the second camera device  316 . According to an example embodiment, the camera devices may include one or more lenses, an image sensor, and/or an image signal processor (ISP). According to an example embodiment, the first camera device  305  may be disposed under the flexible display  330  and may be configured to capture an object through a portion of an active area of the flexible display  330 . For example, the first camera device  305  may not be visually exposed in an active area of the flexible display  330  and may include a hidden under display camera (UDC). According to an example embodiment, the flash  318  may include, for example, a light-emitting diode (LED) or a xenon lamp. In some embodiments, two or more lenses (e.g., a wide-angle lens and a telephoto lens) and image sensors may be disposed on one surface of the electronic device  300 . 
     According to an example embodiment, the electronic device  300  may include at least one antenna (not shown). According to an example embodiment, the at least one antenna may wirelessly communicate with an external electronic device (e.g., the electronic device  104  of  FIG.  1   ), or may wirelessly transmit and receive power required for charging the electronic device  300 . According to an example embodiment, the antenna may include a legacy antenna, a mmWave antenna, a near field communication (NFC) antenna, a wireless charging antenna, and/or a magnetic secure transmission (MST) antenna. In an example embodiment, an antenna structure may be formed through at least a portion of the first side frame  312  and/or the second side frame  322 , which are formed of metal. 
     The electronic device according to an example embodiment may be one of various types of electronic devices. The electronic device may include, for example, a portable communication device (e.g., a smartphone), a computer device, a portable multimedia device, a portable medical device, a camera, a wearable device, or a home appliance device. According to an example embodiment of the disclosure, the electronic device is not limited to those described above. 
     It should be appreciated that various embodiments of the present disclosure and the terms used therein are not intended to limit the technological features set forth herein to particular embodiments and include various changes, equivalents, or replacements for a corresponding example embodiment. In connection with the description of the drawings, like reference numerals may be used for similar or related components. It is to be understood that a singular form of a noun corresponding to an item may include one or more of the things, unless the relevant context clearly indicates otherwise. As used herein, “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “A, B, or C,” each of which may include any one of the items listed together in the corresponding one of the phrases, or all possible combinations thereof. Terms such as “first”, “second”, or “first” or “second” may simply be used to distinguish the component from other components in question, and do not limit the components in other aspects (e.g., importance or order). It is to be understood that if an element (e.g., a first element) is referred to, with or without the term “operatively” or “communicatively”, as “coupled with,” “coupled to,” “connected with,” or “connected to” another element (e.g., a second element), it means that the element may be coupled with the other element directly (e.g., wiredly), wirelessly, or via at least a third element. 
     As used in connection with various embodiments of the disclosure, the term “module” may include a unit implemented in hardware, software, or firmware, and may interchangeably be used with other terms, for example, “logic,” “logic block,” “part,” or “circuitry”. A module may be a single integral component, or a minimum unit or part thereof, adapted to perform one or more functions. For example, according to an example embodiment, the module may be implemented in a form of an application-specific integrated circuit (ASIC). 
     Various embodiments as set forth herein may be implemented as software (e.g., the program  140 ) including one or more instructions that are stored in a storage medium (e.g., an internal memory  136  or an external memory  138 ) that is readable by a machine (e.g., the electronic device  101 ) For example, a processor (e.g., the processor  120 ) of the machine (e.g., the electronic device  101 ) may invoke at least one of the one or more instructions stored in the storage medium, and execute it. This allows the machine to be operated to perform at least one function according to the at least one instruction invoked. The one or more instructions may include a code generated by a compiler or a code executable by an interpreter. The machine-readable storage medium may be provided in the form of a non-transitory storage medium. Here, the term “non-transitory” simply means that the storage medium is a tangible device, and does not include a signal (e.g., an electromagnetic wave), but this term does not differentiate between where data is semi-permanently stored in the storage medium and where the data is temporarily stored in the storage medium. 
     According to an example embodiment, a method according to various embodiments of the disclosure may be included and provided in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or be distributed (e.g., downloaded or uploaded) online via an application store (e.g., PlayStore™), or between two user devices (e.g., smartphones) directly. If distributed online, at least part of the computer program product may be temporarily generated or at least temporarily stored in the machine-readable storage medium, such as memory of the manufacturer&#39;s server, a server of the application store, or a relay server. 
     According to various embodiments, each component (e.g., a module or a program) of the components described above may include a single entity or multiple entities, and some of the multiple entities may be separately disposed in different components. According to various embodiments, one or more of the components described above may be omitted, or one or more other components may be added. Alternatively or additionally, a plurality of components (e.g., modules or programs) may be integrated into a single component. In such a case, according to various embodiments, the integrated component may still perform one or more functions of each of the plurality of components in the same or similar manner as they are performed by a corresponding one of the plurality of components before the integration. According to various embodiments, operations performed by the module, the program, or another component may be carried out sequentially, in parallel, repeatedly, or heuristically, or one or more of the operations may be executed in a different order or omitted, or one or more other operations may be added. 
     Each embodiment herein may be used in combination with any other embodiment described herein. 
       FIG.  5    illustrates an affordance including a plurality of user interface (UI) elements, according to an example embodiment. 
     According to an example embodiment, an electronic device (e.g., the electronic device  101  of  FIG.  1    and the electronic device  300  of  FIG.  3   ) may include a flexible display (e.g., the flexible display  330  of  FIG.  3   ). 
     The flexible display may have a variable size of an exposed area viewed externally as at least a portion of the flexible display is drawn out from the inside of the electronic device. For example, a processor (e.g., the processor  120  of  FIG.  1   , comprising processing circuitry) of the electronic device may control the flexible display based on a user&#39;s input or an application in operation to adjust (or change) the size of the exposed area of the flexible display. 
     The user may desire to quickly adjust the size of the exposed area of the flexible display when the deactivated electronic device is activated. For example, the user may maintain the flexible display in a state in which the flexible display is reduced while the user is carrying the electronic device but not using the electronic device (e.g., in an inactive state) and maintain the flexible display in a state in which the flexible display is expanded while the user is using the electronic device (e.g., in an active state). Accordingly, the user may desire to quickly adjust the size of an exposed area of the flexible display when the electronic device changes from an inactive state to an active state. 
     According to an example embodiment, the electronic device may output an affordance which may adjust the size of an exposed area of the flexible display when the electronic device is activated and adjust the size of the exposed area based on the output affordance, thus satisfying the user&#39;s need for changing the size of the exposed area of the flexible display quickly. 
     Herein, an affordance may be, for example, a visual representation indicating guidance and performance of changing the size of an exposed area of the flexible display viewed from outside. For example, when the affordance for changing the size of the exposed area of the flexible display is selected by a user&#39;s input (e.g., a touch input or a voice input), the affordance may be an object triggering a change in the size of a screen portion viewed on one side of a display screen of the electronic device. For example, the affordance for changing the size of the exposed area of the flexible display may include an expansion affordance indicating that a screen portion viewed is expandable when the size of the screen portion currently viewed is expandable. For example, the affordance for changing the size of the exposed area of the flexible display may include a reduction affordance indicating that a screen portion viewed is reducible when the size of the screen portion currently viewed is reducible. For example, the affordance for changing the size of the exposed area of the flexible display may include both the expansion affordance and the reduction affordance. Also, the affordance for changing the size may include the amount of a predicted change in size. 
     As an example, the electronic device may perform at least one of an output of a graphic representation indicating a scheduled amount of change determined by a pointing input as an affordance for changing the size of the exposed area of the flexible display, an output of a graphic representation indicating a remaining amount of change while the size of the screen portion viewed is being changed, and an output of a graphic representation indicating sizes additionally changeable from the size of the screen portion currently viewed. 
     According to an example embodiment, when the electronic device is activated, one or more app tiles  511  (e.g., icons) or a screen of an application running in the foreground may be output, based on a current size  510  of an exposed area of the flexible display. In addition, the electronic device may additionally output, on at least a portion of the exposed area, an affordance  520  for adjusting the size of the exposed area. For example, the affordance  520  may include a plurality of user interface (UI) elements  521 ,  522 , and  523  indicating sizes. A user may select one of the plurality of UI elements  521 ,  522 , and  523  (e.g., the UI element  521 ), and the electronic device may control the flexible display to adjust the size of the exposed area to a size  530  corresponding to the UI element  521 , in response of the selection of the UI element  521 . The exposed area adjusted to the size  530  output more app tiles  531  (e.g., icons) than the number of app tiles  511  previously output. 
     The user may select any one of the plurality of UI elements  521 ,  522 , and  523  without a complex control process, so that the user may easily and quickly adjust the size of the exposed area. 
     Described hereinafter is a method of adjusting the size of an exposed area of a flexible display with reference to  FIGS.  6  through  21   . 
       FIG.  6    is a flowchart of a method of adjusting the size of an exposed area of a flexible display, according to an example embodiment. 
     Operations  610  to  640  may be performed by an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ). According to an example embodiment, the electronic device may include a processor (e.g., the processor  120  of  FIG.  1   ) and a flexible display (e.g., the display  210  of the display module  160  or the flexible display  330  of  FIG.  3   ). For example, the flexible display may have a variable size of an exposed area viewed outside as at least a portion of the flexible display is drawn out from the inside of the electronic device. 
     In operation  610 , when the flexible display is activated, the processor of the electronic device may output, on at least a portion of the exposed area, an affordance for adjusting the size of an exposed area. 
     For example, when the flexible display that was previously off is turned on, the processor may determine that the flexible display is activated. For example, when a system is unlocked, the processor may determine that the flexible display is activated. For example, when an input for activating the deactivated electronic device is received, the processor may determine that the flexible display is activated. 
     According to an example embodiment, the affordance may include one or more UI elements indicating each of variable sizes of the exposed area. For example, the sizes of the exposed area may be represented as full expansion, half-expansion, or normal. Full expansion may be the maximum size, or a large size, of the exposed area, normal may be the minimum or a small size of the exposed area, and half-expansion may be the size of the exposed area between full expansion and normal. For example, the user may preset at least some of the sizes of the exposed area. The user may set a specific size between normal and full expansion, and the UI elements may indicate set sizes. The user may preset the sizes. 
     When the user selects a specific UI element of the affordance, the electronic device may quickly adjust the size of the exposed area to a size substantially corresponding to the specific UI element. A method of outputting an affordance including one or more UI elements is described in detail below with reference to  FIGS.  7  to  13   . 
     According to an example embodiment, the affordance may include app icons indicating applications executable on the electronic device. The user&#39;s preferable size of the exposed area for a specific application may be preset. When the user intends to execute a specific application through an app icon in the affordance, the electronic device may quickly adjust the size of the exposed area to a preset size while executing the specific application. A method of outputting the affordance including app icons is described in detail below with reference to  FIGS.  14  to  16   . 
     According to an example embodiment, the affordance may include graphic elements to induce a user&#39;s input (e.g., gesture). The electronic device may receive the user&#39;s input through the graphic elements and adjust the size of the exposed area to a size corresponding to the received user&#39;s input. A method of outputting the affordance including graphic elements to induce the user&#39;s input is described in detail below with reference to  FIGS.  17 ,  18 A, and  18 B . 
     According to an example embodiment, although it is described that the first size of the exposed area is identified when the flexible display is activated in operation  610 , the activation of the flexible display may not be a prerequisite to identifying the first size of the exposed area. For example, even when there is no activation event of the flexible display, the processor of the electronic device may identify the first size of the exposed area of the flexible display and output, on at least a portion of the exposed area, the affordance including at least one selectable UI element for changing the size of the exposed area, based on the identified first size. 
     In operation  620 , the processor of the electronic device may receive information about a target size (e.g., a second size) from the user through the affordance. 
     According to an example embodiment, the user may touch (or select) a target UI element among one or more UI elements in the affordance output on the exposed area, so that the user may input information about the target size to the electronic device. 
     For example, the user may touch (or select) a target app icon among app icons in the affordance output on the exposed area. The processor may determine information about the target size associated with the selected target app icon. 
     For example, the user may perform an input (e.g., dragging and releasing) on the graphic elements of the affordance output on the exposed area so that the user may input information about the target size to the electronic device. 
     According to an example embodiment, the user may input a voice representing the target UI element among the one or more UI elements of the affordance output on the exposed area, so that the user may input information about the target size to the electronic device. 
     When information about the target size has been received from the user, the processor may suspend output of the affordance. That is, the output affordance may be removed. 
     In operation  630 , the processor of the electronic device may control the flexible display to have the size of the exposed area correspond to the target size. For example, the processor may adjust the size of the flexible display, using the driving unit in the first space and/or the second space described with reference to  FIG.  3   . 
     According to an example embodiment, in operation  630 , when one UI among the at least one UI element in the output affordance is selected, the processor of the electronic device may control the driving unit to change the size of the exposed area from a first size (e.g., the current size) to a second size (e.g., the target size) corresponding to the selected UI element. 
     In operation  640 , when the user&#39;s input to the affordance is not performed within a preset time (e.g., operation  620  is not performed), the processor of the electronic device may suspend output of the affordance. For example, the electronic device may suspend output of the affordance so that the affordance disappears immediately or gradually. 
     According to an example embodiment, the preset time for the output affordance may be set differently depending on the type, form, or output state of the affordance. For example, the preset time for each affordance described with reference to the drawings (e.g., the affordance  520  of  FIG.  5   , an affordance  820  of  FIG.  8 A , an affordance  840  of  FIG.  8 B , an affordance  860  of  FIG.  8 C , an affordance  1032  of  FIG.  10   , an affordance  1220  of  FIG.  12   , an affordance  1530  of  FIG.  15   , an affordance  1620  of  FIG.  16   , an affordance  1820  of  FIG.  18 A , an affordance  1860  of  FIG.  18 B , an affordance  1910  of  FIG.  19 A , an affordance  1920  of  FIG.  19 B , an affordance  1930  of  FIG.  19 C , and an affordance  2122  of  FIG.  21   ) may be different from another. 
       FIG.  7    is a flowchart of a method of outputting an affordance to include one or more UI elements, according to an example embodiment. 
     According to an example embodiment, operation  610  described above with reference to  FIG.  6    may include operations  710  through  740  to be described hereinafter with reference to  FIG.  7   . 
     In operation  710 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may determine (or identify) a current size (e.g., the first size) of an exposed area when a flexible display (e.g., the display  210  of the display module  160  or the flexible display  330  of  FIG.  3   ) of the electronic device is activated. 
     According to an example embodiment, the current size of the exposed area may be determined to be any one of normal, half-expansion, and full-expansion. Although it has been described in an embodiment that the sizes of the exposed area are classified into normal, half-expansion, and full expansion, the type and shape of sizes of the exposed area is not limited to the described embodiment. For example, the sizes of the exposed area may be defined based on a screen ratio. 
     In operation  720 , the processor of the electronic device may determine a plurality of UI elements representing each of the sizes, based on the current size. For example, the processor may determine one or more UI elements representing each of the one or more sizes, based on the current size. 
     According to an example embodiment, even if UI elements indicate the same size, a term indicating the size corresponding to the term may vary depending on the current size and the plurality of UI elements may be set to include a term indicating its corresponding size. The plurality of UI elements representing each of the sizes, based on a current size, are described in detail below with reference to  FIGS.  8 A to  8 C . 
     In operation  730 , the processor of the electronic device may generate an affordance to include the plurality of UI elements. For example, the arrangement of the plurality of UI elements in the affordance may vary depending on a determined current size (e.g., the current size determined in operation  710 ). 
     In operation  740 , the processor of the electronic device may output the generated affordance on at least a portion of the exposed area of the flexible display. For example, the affordance may be output at a position that a user easily touches with their finger(s) or other input member. The user may predetermine the position at which the affordance is output. 
       FIGS.  8 A- 8 C  illustrate a plurality of affordances that may vary depending on a current size of an exposed area, according to an embodiment. 
       FIG.  8 A  illustrates an affordance  820  output when a current size  810  of an exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ) is normal,  FIG.  8 B  illustrates an affordance  840  output when a current size  830  of an exposed area is half-expansion, and  FIG.  8 C  illustrates an affordance  860  output when a current size  850  of an exposed area is full or substantially full expansion. 
     According to an example embodiment, a graphic element and a text element in each of UI elements included in the affordances  820 ,  840 , or  860  may vary depending on a relationship between a current size and the size corresponding to each of the UI elements. For example, a size may be expanded when the current size, which is the normal, is adjusted to half-expansion but a size may be reduced when the current size, which is full expansion, is adjusted to half-expansion. 
     In one example with reference to  FIG.  8 A , the processor may generate a first UI element  821  for full expansion, a second UI element  822  for half-expansion, and a third UI element  823  for normal. Since the current size is normal, the third UI element  823  may not include a right arrow indicating that the exposed area is to be expanded or a left arrow indicating that the exposed area is to be reduced. The first UI element  821  and the second UI element  822  may include the right arrow indicating that the exposed area is to be expanded compared to the current size. Also, the third UI element  823  corresponding to the current size may be disposed at the bottom of the affordance  820 , and the first UI element  821  and the second UI element  822  may be disposed in the upper part of the affordance  820 . The arrangement of the UI elements  821 ,  822 , and  823  in the affordance  820  may vary depending on an example embodiment. 
     In one example with respect to  FIG.  8 B , the processor may generate a first UI element  841  for normal, a second UI element  842  for full expansion, and a third UI element  843  for half-expansion. Since the current size is half-expansion, the third UI element  843  may not include a right arrow indicating that the exposed area is to be expanded or a left arrow indicating that the exposed area is to be reduced. The first UI element  841  may include the left arrow indicating that the exposed area is to be reduced compared to the current size. The second UI element  842  may include the right arrow indicating that the exposed area is to be expanded compared to the current size. In addition, the third UI element  843  corresponding to the current size may be disposed at the bottom of the affordance  840 , and the first UI element  841  and the second UI element  842  may be disposed in the upper part of the affordance  840 . The arrangement of the UI elements  841 ,  842 , and  843  in the affordance  840  may vary depending on an example embodiment. 
     In one example with respect to  FIG.  8 C , the processor may generate a first UI element  861  for normal, a second UI element  862  for half-expansion, and a third UI element  863  for full expansion. Since the current size is full expansion, the third UI element  863  may not include the right arrow indicating that the exposed area is to be expanded or the left arrow indicating that the exposed area is to be reduced. The first UI element  861  and the second UI element  862  may include the left arrow indicating that the exposed area is reduced compared to the current size. In addition, the third UI element  863  corresponding to the current size may be disposed at the bottom of the affordance  860 , and the first UI element  861  and the second UI element  862  may be disposed in the upper part of the affordance  860 . The arrangement of the UI elements  861 ,  862 , and  863  in the affordance  860  may vary depending on an example embodiment. 
     Although the affordances including the UI elements indicating the sizes of the exposed area are described with reference to  FIGS.  8 A to  8 C , user settings other than the size of the exposed area may be available for the UI elements. 
     According to an example embodiment, a UI element of the affordance may indicate an aspect ratio of the exposed area. For example, the aspect ratio of the exposed area may include a normal ratio, a 4:3 ratio, a 16:9 ratio, and a full expansion ratio. According to an example embodiment, the UI element of the affordance may indicate a specific layout of a screen output in the exposed area. For example, the layout of the screen may include a mobile layout and a tablet layout. 
     According to an example embodiment, the UI element of the affordance may indicate the number of split screens output in the exposed area. For example, the number of split screens may be 2 to 4. 
       FIG.  9    is a flowchart of a method of outputting an affordance generated based on a previous size of an exposed area before a flexible display is deactivated, according to an example embodiment. 
     According to an example embodiment, operation  610  described above with reference to  FIG.  6    may include operations  910  through  940  to be described hereinafter with reference to  FIG.  9   . 
     In operation  910 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may determine a previous size before the deactivation of a flexible display (e.g., the display  210  of the display module  160  or the flexible display  330  of  FIG.  3   ). That is, the size of the exposed area at the time of the activation of the flexible display may be determined to be the previous size. 
     For example, the size of the exposed area when a user presses a screen-off button may be determined to be the previous size. For example, the size of the exposed area when the user locks a system may be determined to be the previous size. 
     In operation  920 , the processor of the electronic device may determine an additional UI element indicating the previous size. 
     In operation  930 , the processor of the electronic device may generate an affordance to include one or more UI elements (e.g., the UI elements  821 ,  822 , and  823  of  FIG.  8 A , the UI elements  841 ,  842 , and  843  of  FIG.  8 B , or the UI elements  861 ,  862 , and  863  of  FIG.  8 C ) and an additional UI element. The additional UI element and the affordance including the additional UI element are described in detail hereinafter with reference to  FIG.  10   . 
     In operation  940 , the processor of the electronic device may output the generated affordance on at least a portion of the exposed area of the flexible display. 
       FIG.  10    illustrates an affordance including an additional UI element generated based on a previous size of an exposed area before the deactivation of a flexible display, according to an example embodiment. 
     In operation  1010 , a size  1011  of the exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    and the electronic device  300  of  FIG.  3   ) may be half-expanded. Afterwards, for example, a user may press a screen-OFF button to deactivate the flexible display. The size of the exposed area when the flexible display is deactivated may be half-expansion. 
     In operation  1020 , the user may adjust the size of the exposed area in a state in which the flexible display is deactivated. For example, the user may adjust a size  1021  of the exposed area to normal, using a physical force. Afterwards, for example, the user may press a screen-ON button to activate the flexible display. 
     In operation  1030 , the processor of the electronic device may determine a previous size (e.g., half-expansion) before the deactivation of the flexible display and an additional UI element  1033  indicating the previous size. Additionally, the processor may determine a current size  1031  and determine one or more UI elements  1034 ,  1035 , and  1036  based on the current size  1031 . The processor may generate an affordance  1032  to include the additional UI element  1033  and the one or more UI elements  1034 ,  1035 , and  1036  and may output the affordance  1032 . 
       FIG.  11    is a flowchart of a method of outputting an affordance generated based on an application running in the foreground, according to an example embodiment. 
     According to an example embodiment, operation  610  described above with reference to  FIG.  6    may include operations  1110  through  1140  to be described hereinafter with reference to  FIG.  11   . 
     In operation  1110 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may determine (or identify) an application running in the foreground. For example, an application running in a single window may be determined to be the application running in the foreground. For example, applications being executed in a multi-window may be determined to be the applications being executed in the foreground. 
     In operation  1120 , the processor of the electronic device may determine an additional UI element indicating a size preset for a determined application. For example, a user may preset a size for its corresponding application. For example, the processor may preset a size for a corresponding application based on the history of the size set during the execution of the corresponding application in the foreground. 
     According to an example embodiment, the additional UI may include an app icon and a text element indicating the corresponding application. 
     In operation  1130 , the processor of the electronic device may generate an affordance to include one or more UI elements (e.g., the UI elements  821 ,  822 , and  823  of  FIG.  8 A , the UI elements  841 ,  842 , and  843  of  FIG.  8 B , or the UI element  861 ,  862 , and  863  of  FIG.  8 C ) and an additional UI element. 
     In operation  1140 , the processor of the electronic device may output the generated affordance on at least a portion of the exposed area of the flexible display.  FIG.  12    illustrates an affordance including an additional UI element generated based on an application running in the foreground, according to an example embodiment. 
     In operation  1210 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may determine an application (e.g., an e-mail application) running in the foreground. Also, the processor may determine a size  1211  (e.g., normal) of an exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ). 
     The processor may determine an additional UI element  1221  representing a preset size (e.g., half-expansion) of an e-mail application and one or more UI elements  1222 ,  1223 , and  1224 , based on the current size, which is the size  1211 . The processor may generate and output an affordance  1220  to include the additional UI element  1221  and the one or more UI elements  1222 ,  1223 , and  1224 . For example, a user may select the additional UI element  1221  in the affordance  1220 . 
     In operation  1220 , the processor may control the flexible display to have the size of the exposed area of the flexible display correspond to the size of the additional UI element  1221  (e.g., half-expansion and/or expansion to a previous size). For example, as the exposed area of the flexible display increases, the email application may further output a new menu  1222 . As the exposed area of the flexible display increases, the user may more comfortably and efficiently use the e-mail application. 
       FIG.  13    is a flowchart of a method of changing a color of a target UI element, based on the remaining capacity of a battery, according to an example embodiment. 
     According to an example embodiment, operation  1310  described below may be performed before operation  720  described above with reference to  FIG.  7   . Additionally, operation  720  may include the operation  1320 . 
     In operation  1310 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may determine (or identify) the remaining capacity of a battery (e.g., the battery  189  of  FIG.  1   ). 
     In operation  1320 , the processor of the electronic device may change a color of a target IU element differently from other IU elements, based on the remaining capacity of the battery, among one or more UI elements (e.g., the UI elements  821 ,  822 , and  823  of  FIG.  8 A , the UI elements  841 ,  842 , and  843  of  FIG.  8 B , or the UI elements  861 ,  862 , and  863  of  FIG.  8 C ). In an example embodiment, the processor may identify state information of the electronic device corresponding to the target UI element and determine the one or more UI elements based on the state information of the electronic device. For example, the processor may determine a target UI element representing a specific size among the one or more UI elements based on the state information (e.g., the remaining capacity of the battery) and may set a color of the determined target UI element differently from the other UI elements. 
     According to an example embodiment, when the remaining capacity of the battery is less than a preset threshold value (e.g., 5%), the processor may induce a user to keep the size of the flexible display (e.g., the flexible display  330  of  FIG.  3   ) small by displaying colors of the UI elements differently. For example, when the current size is normal, the UI elements indicating expansion may be displayed in red not to recommend to increase the exposed area and the UI elements indicating remaining in the current size may be displayed in green. For example, when the current size is half-expansion or full expansion, the UI element indicating reducing the exposed area may be displayed in green. 
     In an example embodiment, although the battery (e.g., the remaining capacity of the battery) is described as state information of the electronic device corresponding to one or more UI elements, information other than the battery may be included. For example, the processor may determine an operation state of a driving unit (e.g., a motor), a layout of a screen set by a user (e.g., the mobile layout and the tablet layout) and/or the number of split screens to be state information on the electronic device. For example, two UI elements (e.g., the UI elements  821  and  823  of  FIG.  8 A ) may be determined to be the state information of the layout and three 
     UI elements (e.g., the UI elements  821 ,  822 , and  823  of  FIG.  8 A ) may be determined to be the state information of the split screens. In an example embodiment, the processor may change a color of a target UI element (e.g., a UI element indicating a specific size among one or more UI elements) to be different from other UI elements based on change in the determined state information. 
     A method of outputting an affordance including one or more UI elements representing each size is described with reference to  FIGS.  7  to  13   . Described hereinafter with reference to  FIGS.  14  to  17    is a method of executing an application and adjusting the size of an exposed area when a flexible display is activated. 
       FIG.  14    is a flowchart of a method of outputting an affordance generated based on target applications, controlling a flexible display based on an affordance selection input, and executing an application, according to an example embodiment. 
     According to an example embodiment, operation  610  described above with reference to  FIG.  6    may include operations  1410  to  1430 , operation  620  may include operation  1440 , and operation  630  may include operation  1450 . 
     In operation  1410 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may determine a preset number of target applications when a flexible display (e.g., the flexible display  330 ) is activated. 
     For example, an application frequently executed by a user may be determined to be a target application. The application frequently executed by a user may change based on execution history. 
     For example, an application registered as a shortcut by the user may be determined to be the target application. 
     For example, an application running in the foreground before the deactivation of the flexible display may be determined to be the target application. 
     For example, applications executed in the foreground in a multi-window before the deactivation of the flexible display may be determined to be target applications. 
     In operation  1420 , the processor may determine app icons representing each of the target applications. For example, the app icon may be an app tile image or a symbol image of a corresponding application. 
     In operation  1430 , the processor may generate an affordance to include app icons. The affordance including the app icons is described in detail with reference to  FIG.  15   . 
     In operation  1440 , the processor may receive an input of the selection of a first app icon from the user through the affordance. For example, the user may touch the first app icon indicating a target application that the user intends to execute among output app icons. For example, the selection of the first app icon may be input by dragging the first app icon to a preset target area on the exposed area. The input of the drag selection is described in detail below with reference to  FIG.  16   . 
     In operation  1450 , the processor may control the flexible display to have the size of the exposed area of the flexible display correspond to a third size associated with the first app icon. For example, the processor may control the flexible display by controlling a driving unit (or driving module). 
     According to an aspect, the size of the exposed area may be preset for a first application indicated by the first app icon. For example, regarding the first target application, the processor may associate, with the first target application, the third size that the user designates for the first target application in advance. For example, the processor may associate the first target application with the third size in advance, based on the history of the size of the exposed area set during the execution of the first target application in the foreground. 
     In operation  1460 , the processor may execute the first target application in the foreground. 
     For example, operations  1450  and  1460  may be performed concurrently. For example, any one of operations  1450  and  1460  may be performed first. 
       FIG.  15    illustrates an affordance including app icons generated based on target applications, according to an example embodiment. 
     In operation  1510 , a user may perform an input to activate a flexible display (e.g., the flexible display  330 ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ). 
     For example, the user&#39;s input may be a knock on the flexible display. 
     For example, the user&#39;s input may be a drag input  1512 , which is an input of drag a length greater than or equal to a preset length on the flexible display. A processor (e.g., the processor  120  of  FIG.  1   ) of the electronic device may calculate a length of the drag input  1512  from a coordinate  1513  at which a first touch occurs and activate the flexible display in response to the drag input  1512 , which drags to the length equal to or greater than the preset length. The drag input  1512  may be held or released at a coordinate  1514 . 
     For example, the user&#39;s input may be a pattern drag. When the pattern drag matches a preset encryption pattern, the processor may activate the flexible display. 
     According to an example embodiment, when the flexible display is activated, the processor may determine a size  1511  of an exposed area. 
     In operation  1520 , when the user&#39;s input activates the flexible display, the processor of the electronic device may determine target applications and may determine app icons  1531 ,  1532 ,  1533 , and  1534  respectively representing the target applications. For example, the app icon  1531  may correspond to a contact information application, the app icon  1532  may correspond to a message application, the app icon  1533  may correspond to a settings application, and the app icon  1534  may correspond to a multi-window application. 
     According to an example embodiment, the target applications (or the app icons  1531 ,  1532 ,  1533 , and  1534 ) may be determined based on the size  1511  determined of the exposed area. 
     The processor may generate an affordance  1530  to include the app icons  1531 ,  1532 ,  1533 , and  1534 . For example, the processor may determine a coordinate (e.g., coordinate  1514 ) touched last by the user and output the affordance  1530  near the determined coordinate. 
     For example, when the user is holding the touch at the coordinate  1514 , the user may select an app icon by dragging the touch in the direction of an app icon corresponding to the target application that the user intends to execute. 
     For example, when the user releases the touch at the coordinate  1514 , the user may select an app icon by touching an app icon (e.g., the app icons  1531 ,  1532 ,  1533 , and  1534 ) corresponding to the target application the user intends execute. 
     The processor may control the flexible display to adjust the size of the exposed area to the size associated with the selected app icon. Also, the processor may execute the target application corresponding to the app icon in the foreground. When the app icon  1534  representing the multi-window is selected, the processor may adjust the size of the exposed area to a size supported by the multi-window and execute, in the foreground through the multi-window, the applications that have been executed in the multi-window before the activation of the flexible display. 
       FIG.  16    illustrates a method in which an app icon selected by a user is dragged to a preset target area in an exposed area, according to an example embodiment. 
     In operation  1610 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may output an affordance  1620  including app icons  1622 ,  1624 ,  1626 , and  1628 . For example, the location of the affordance  1620  may be determined based on a coordinate  1614  touched last by a user. 
     According to an example embodiment, a portion of an exposed area of a flexible display (the flexible display  330 ) may be preset as a target area  1630 . The target area  1630  may be a selection area. 
     In operation  1640 , the user may transmit a selection input to the electronic device by dragging, to the target area  1630 , the app icon  1626  of an application that the user intends to execute. For example, when the user&#39;s touch is released in a state in which the dragged app icon  1626  is positioned within the target area  1630 , the processor may determine that the selection input of the app icon  1626  has been received from the user. 
       FIG.  17    is a flowchart of a method of outputting an affordance based on a coordinate of a reference display determined based on a user&#39;s touch input, according to an example embodiment. 
     According to an example embodiment, operation  610  described above with reference to  FIG.  6    may include operations  1710  through  1750  to be described hereinafter with reference to  FIG.  17   . 
     In operation  1710 , a processor (e.g., the processor  120  of  FIG.  1   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may determine whether a touch input continues for a preset time based on a user&#39;s touch input when a flexible display (e.g., the flexible display  330  of  FIG.  3   ) is activated. The user may maintain a touch input for the preset time even after the activation of the flexible display to transmit, to the electronic device, their intention to adjust the size of the flexible display through the affordance. 
     In operation  1720 , when the touch input continues for the preset time, the processor of the electronic device may determine a reference display coordinate of the touch input. For example, the processor may determine any one coordinate (e.g., the center coordinate) on the touch input is to be the reference display coordinate. 
     In operation  1730 , the processor of the electronic device may determine a current size of the exposed area of the flexible display. 
     In operation  1740 , the processor of the electronic device may generate an affordance including graphic elements representing sizes different from the current size. For example, the graphic elements may be concentric circles with different radii. The affordance including graphic elements is described in detail below with reference to  FIGS.  18 A and  18 B . 
     In operation  1750 , the processor of the electronic device may output the affordance based on the reference display coordinate. 
       FIGS.  18 A and  18 B  illustrate a method of receiving a drag input from a user with respect to an affordance output based on a reference display coordinate, according to an example embodiment. 
       FIG.  18 A  illustrates a case where a current size  1811  of an exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ).) is normal. 
     In operation  1810 , a processor (e.g., the processor  120  of  FIG.  1   ) of the electronic device may output an affordance  1820  including graphic elements  1822  and  1824 , based on a reference display coordinate  1812  of a touch input. 
     The graphic elements  1822  and  1824  may be determined based on the current size  1811  of the exposed area of the flexible display. For example, when the current size  1811  of the exposed area is normal, the graphic element  1822  having a relatively smaller radius than the graphic element  1824  may represent half-expansion and the graphic element  1824  having a relatively larger radius than the graphic element  1822  may represent full expansion. 
     The user may transmit information about a target size to the electronic device by dragging a touch to a graphic element (e.g., the graphic element  1822 ) corresponding to a desired size of the exposed area from the reference display coordinate  1812 , in operation  1830 . 
     Although in an illustrated embodiment the affordance  1820  is described as an affordance including the graphic elements  1822  and  1824  with different radii of concentric circles, according to an example embodiment, the affordance  1820  may include circular graphic elements with respect to the reference display coordinates  1812  and a drag touch may be performed from the reference display coordinate  1812  within the boundary of a graphic element in order to transmit information about a desired target size to the electronic device. The target size may be determined based on a proportion of a drag from the reference display coordinate  1812  to the boundary of the graphic element. 
     In operation  1840 , the processor of the electronic device may determine a target size  1841  of the exposed area corresponding to the drag input and control the flexible display to have the size of the exposed area correspond to the target size  1841 . 
       FIG.  18 B  illustrates a case where a current size  1851  of an exposed area of the flexible display of the electronic device is full expansion. 
     In operation  1850 , the processor of the electronic device may output an affordance  1860  including graphic elements  1862  and  1864  based on reference display coordinates  1852  of a touch input. 
     The graphic elements  1862  and  1864  may be determined based on the current size  1851  of the exposed area of the flexible display. For example, when the current size  1851  of the exposed area is full expansion, the graphic element  1862  with a relatively smaller radius may represent half-expansion and the graphic element  1864  with a relatively larger radius may represent normal. A text element of “half reduction” may be output in association with the graphic element  1862  since the size of the exposed area needs to be reduced in half to adjust the size of the exposed area from full expansion to half-expansion. Similarly, a text element of “full reduction” may be output in association with the graphic element  1864  since the size of the exposed area needs to be fully reduced in order to adjust the size of the exposed area from full expansion to normal. 
     A user may transmit information on a target size to the electronic device by dragging a touch from the reference display coordinates  1852  to a graphic element (e.g., the graphic element  1864 ) corresponding to the desired size of the exposed area, in operation  1870 . 
     In operation  1880 , the processor of the electronic device may determine a target size  1881  of the exposed area corresponding to a drag input  1870  and control the flexible display to have the size of the exposed area correspond to the target size  1881 . 
       FIGS.  19 A,  19 B, and  19 C  illustrate a plurality of affordances according to various embodiments. 
       FIG.  19 A  illustrates a diagram illustrating an affordance  1910  representing a plurality of sizes of an exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ). 
     According to an example embodiment, an affordance may include a gauge to control the size of the exposed area of the flexible display. The gauge may include points  1911 ,  1913 ,  1915 , and  1917 , and each of the points  1911 ,  1913 ,  1915 , and  1917  may indicate a corresponding size of an exposed area. For example, the point  1911  located leftmost in the gauge may indicate the size of normal and the point  1917  located rightmost in the gauge may indicate the size of full expansion. For example, the affordance  1910  may further include graphic effects  1912  and  1918  to visually convey, to a user, the indication that the point  1911  represents normal and that point  1917  represents full expansion. The points  1913  and  1915  located between the points  1911  and  1917  may represent sizes between normal and full expansion. The user may select any one of the points  1911 ,  1913 ,  1915 , and  1917  to select the size of the exposed area. 
       FIG.  19 B  is a diagram illustrating an affordance  1920  representing sizes of an exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ). 
     According to an example embodiment, the affordance  1920  may include a gauge  1922  to control the size of the exposed area of the flexible display. The gauge  1922  may include areas (e.g., Step  1 , Step  2 , and Step  3 ), and each of the areas may indicate a corresponding size of the exposed area. For example, the leftmost area (e.g., Step  1 ) of the gauge  1922  may indicate the size of normal and the rightmost region (e.g., Step  3 ) of the gauge  1922  may indicate the size of full expansion. 
     According to an example embodiment, the affordance  1920  may further include a graphic effect  1924  to visually convey, to a user, the size of the exposed area corresponding to a selected area. The graphic effect  1924  may be output differently according to an area selected by the user in the gauge  1922 . For example, a graphic effect may be output which corresponds to an area that the user is selecting by a drag touch. The size of the exposed area may be adjusted to a size corresponding to the area, on which the user releases the touch. 
       FIG.  19 C  is a diagram illustrating an affordance  1930  representing sizes of an exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ). 
     According to an example embodiment, the affordance  1930  may include a gauge  1932  to control the size of the exposed area of the flexible display. A user may move a point  1934  in the gauge  1932  to input a desired size of the exposed area to the electronic device. For example, the leftmost side of the gauge  1932  may indicate the size of normal and the rightmost side of the gauge  1932  may indicate the size of full expansion. For example, the affordance  1930  may further include graphic effects  1936  and  1938  to visually provide, to the user, the indication that the leftmost side of the gauge  1932  indicates the size of normal and the rightmost side of the gauge  1932  indicates the size of full expansion. The user may move the point  1934  within the gauge  1932  to select the size of the exposed area. For example, the point  1934  may be moved in a free-stop manner, but is not limited to the described embodiment. 
       FIG.  20    is a flowchart of a method of outputting an additional affordance when an input of deactivating a flexible display is received and controlling a flexible display based on the additional affordance, according to an example embodiment. 
     Operations  2010  to  2040  may be performed by an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ). According to an example embodiment, the electronic device may include a processor (e.g., the processor  120  of  FIG.  1   ) and a flexible display (e.g., the display  210  of the display module  160  or the flexible display  330  of  FIG.  3   ). 
     In operation  2010 , in response to receiving an input of deactivating the flexible display, the processor of the electronic device may output an additional affordance, which adjusts the size of an exposed area of the flexible display, on at least a portion of the exposed area. 
     For example, when a user presses a screen-OFF button, the processor may determine that an input of deactivating the flexible display is received. 
     For example, the additional affordance may include one or more UI elements representing each size. The additional affordance may include a UI element indicating the minimum or a small size of the exposed area. 
     In operation  2020 , the processor of the electronic device may receive information about a fourth size from the user through the additional affordance. For example, when the user touches a target UI element of the additional affordance, the processor may determine a second target size indicated by the target UI element. 
     In operation  2030 , the processor of the electronic device may control the flexible display to have the size of the exposed area correspond to the fourth size. For example, the processor may control a driving unit (or a driving module) to control the flexible display. 
     Each “module” here may comprise circuitry. 
     In operation  2040 , the processor of the electronic device may deactivate the flexible display. 
     According to an example embodiment, operations  2010  through  2040  may be performed after operation  640  described with reference to  FIG.  6    is performed. 
       FIG.  21    illustrates a method of outputting an additional affordance when an input of deactivating the flexible display is received and controlling the flexible display based on the additional affordance, according to various embodiments. 
     In operation  2110 , a size  2111  of an exposed area of a flexible display (e.g., the flexible display  330  of  FIG.  3   ) of an electronic device (e.g., the electronic device  101  of  FIG.  1    and the electronic device  300  of  FIG.  3   ) may be half-expansion. Thereafter, for example, a user may press a screen-OFF button to transfer a deactivation input to the electronic device. 
     In operation  2120 , a processor (e.g., the processor  120  of  FIG.  1   ) of the electronic device may generate and output an additional affordance  2122  to adjust the size of the exposed area. For example, the additional affordance  2122  may include one or more UI elements  2123 . The UI element  2123  may be associated with normal. 
     According to an example embodiment, the processor may blur or darken the screen of the exposed area and brighten only a portion in which the additional affordance  2122  is output, in response to an input of deactivating the flexible display. 
     The user may touch the UI element  2123  of the additional affordance  2122  to input information about the fourth size to the electronic device. 
     In operation  2130 , the processor of the electronic device may control the flexible display to have the size of the exposed area correspond to a second target size  2131  and then deactivate the flexible display. Contrary to the above, the processor of the electronic device may deactivate the flexible display and then control the flexible display to have the size of the exposed area correspond to the second target size  2131 . 
     According to an example embodiment, an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may include a driving module, a flexible display (e.g., the flexible display of  FIG.  3   ) having a variable size of an exposed area viewed externally on one side as at least a portion of the flexible display is drawn out from the inside of the electronic device by driving of the driving module (comprising a motor and/or circuitry), at least one memory (e.g., the memory  130  of  FIG.  1   ) configured to store executable instructions, and a at least one processor (e.g., the processor of  FIG.  1   ) configured to be operatively connected, directly or indirectly, to the driving module, the flexible display, and the at least one memory and control the electronic device. The at least one processor may be configured by executing the instructions to identify a first size of the exposed area, output, on at least a portion of the exposed area, an affordance (e.g., the affordance  520  of  FIG.  5   , the affordance  820  of  FIG.  8 A , the affordance  840  of  FIG.  8 B , the affordance  860  of  FIG.  8 C , the affordance  1032  of  FIG.  10   , the affordance  1220  of  FIG.  12   , the affordance  1530  of  FIG.  15   , the affordance  1620  of  FIG.  16   , the affordance  1820  of  FIG.  18 A , the affordance  1860  of  FIG.  18 B , the affordance  1910  of  FIG.  19 A , the affordance  1920  of  FIG.  19 B , or the affordance  1930  of  FIG.  19 C ) including at least one selectable UI element configured to change the size of the exposed area based on the identified first size, and when a UI element is selected from among the at least one UI element, control the driving module to change the size of the exposed area from the first size to a second size corresponding to a selected UI element. 
     According to an example embodiment, the processor may be configured by executing the instruction to determine at least one selectable UI element representing at least one size, based on the identified first size and generate the affordance to include the at least one determined UI element. 
     According to an example embodiment, an arrangement of the at least one UI element in the affordance may vary depending on the identified first size. 
     According to an example embodiment, the processor may be configured by executing the instructions to determine a previous size before the deactivation of the flexible display, determine an additional UI element indicating the previous size, and generate the affordance to include at the least one UI element and the additional UI element. 
     According to an example embodiment, the processor may be configured by executing the instructions to identify an application being executed in the foreground, determine an additional UI element indicating a preset size for the application, and generate an affordance to include the at least one UI element and the additional UI element. 
     According to an example embodiment, the electronic device may further include a battery (e.g., the battery  189  of  FIG.  1   ) configured to supply power to the electronic device, and the processor may be configured by executing the instructions to identify the remaining capacity of the battery and change a color of a selected UI element differently from other UI elements among the at least one UI element. 
     According to an example embodiment, the processor may be configured by executing the instructions to suspend an output of the affordance when a user&#39;s input to the affordance is not received within a preset time. 
     According to an example embodiment, the processor may be configured by executing the instructions to determine that the flexible display is active when the electronic device is unlocked and identify the first size of the exposed area when the flexible display is activated. 
     According to an example embodiment, the processor may be configured by executing the instructions to determine that the flexible display is active when an input of activating the deactivated electronic device is received and may identify the first size of the exposed area when the flexible display is activated. 
     According to an example embodiment, the processor may be configured by executing the instructions to determine a preset number of target applications when the flexible display is activated and determine a plurality of app icons respectively representing the target applications, wherein a first app icon of the plurality of app icons is associated with a third size preset for the first target application, may generate the affordance to include the plurality of the app icons, may control the driving module to have the size of the exposed area correspond to the third size when an input of the selection of the first app icon is received based on the affordance, and execute the first target application in the foreground. 
     According to an example embodiment, the preset number of target applications may be applications executed in the foreground of the electronic device in a multi-window before the deactivation of the flexible display. 
     According to an example embodiment, the processor is configured by executing the instructions to generate the affordances to include the plurality of app icons and an additional icon representing the multi-window, control the flexible display to have the size of the exposed area correspond to the size of the multi-window when the input of the selection of the additional icon is received through the affordance, and execute the target applications in the foreground through the multi-window. 
     According to an example embodiment, the processor may be configured by executing the instructions to preset a third size of the first target application based on history of the size of the exposed area set during the execution of the first target application in the foreground. 
     According to an example embodiment, the input of the selection of the first app icon may be an input of dragging the first app icon to a preset target area in the exposed area. 
     According to an example embodiment, the processor may be configured by executing the instructions to determine whether the touch input continues for a preset time when the flexible display is activated based on a user&#39;s touch input, determine a reference display coordinate of the touch input when the touch input continues for the preset time, determine the first size of the exposed area, generate the affordance including graphic elements representing sizes different from the first size, and output the affordance based on the reference display coordinate. “Based on” as used herein covers based at least on. 
     According to an example embodiment, the processor may be configured by executing the instructions to receive a drag input indicating the second size from the user through the affordance. 
     According to an example embodiment, the processor may be configured by executing the instructions to output an additional affordance for adjusting the size of the exposed area of at least a portion of the exposed area, when an input of deactivating the flexible display is received, control the driving module to change the size of the exposed area to a fourth size corresponding to the input to the additional affordance, and deactivate the flexible display. 
     According to an example embodiment, a method performed by an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may include, when a flexible display (e.g., the flexible display  330  of  FIG.  3   ) has a variable size of an exposed area viewed externally on one side as at least a portion of the flexible display is drawn out from the inside of the electronic device and the flexible display is activated, outputting, on at least a portion of the exposed area, an affordance for adjusting the size of the exposed area (e.g., the affordance  520  of  FIG.  5   , the affordance  820  of  FIG.  8 A , the affordance  840  of FIG. 
       8 B, the affordance  860  of  FIG.  8 C , the affordance  1032  of  FIG.  10   , the affordance  1220  of  FIG.  12   , the affordance  1530  of  FIG.  15   , the affordance  1620  of  FIG.  16   , the affordance  1820  of  FIG.  18 A , the affordance  1860  of  FIG.  18 B , the affordance  1910  of  FIG.  19 A , the affordance  1920  of  FIG.  19 B , or the affordance  1930  of  FIG.  19 C ) (e.g., operation  610  of  FIG.  6   ), identifying a target size of the exposed area, based on an input to the affordance (e.g., operation  620  of  FIG.  6   ), and controlling a driving module (comprising a motor and/or circuitry) configured to move the flexible display to have the size of the exposed area correspond to the target size (e.g., operation  630  of  FIG.  6   ). 
     According to an example embodiment, an electronic device (e.g., the electronic device  101  of  FIG.  1    or the electronic device  300  of  FIG.  3   ) may include a flexible display (e.g., the flexible display  330  of  FIG.  3   ) having a variable size of an exposed area viewed externally on one side as at least a portion of the flexible display is drawn out from the inside of the electronic device, at least one memory (e.g., the memory  130  of  FIG.  1   ) configured to store executable instructions, and at least one processor (e.g., the processor  120  of  FIG.  1   ) configured to control the electronic device. The processor may be configured to output, on at least a portion of an exposed area, an additional affordance (e.g., the affordance  2122  of  FIG.  21   ) configured to adjust the size of the exposed area when an input of deactivating the flexible display is received, receive information on the size of a second target based on the additional affordance, control the flexible display to have the size of the exposed area correspond to the size of the second target, and deactivate the flexible display. 
     The embodiments described herein may be implemented using a hardware component, a software component and/or a combination thereof. A processing device may be implemented using one or more general-purpose or special-purpose computers, such as, for example, a processor, a controller and an arithmetic logic unit (ALU), a DSP, a microcomputer, a field-programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor or any other device capable of responding to and executing instructions in a defined manner 
     The processing device may run an OS and one or more software applications that run on the OS. The processing device also may access, store, manipulate, process, and create data in response to execution of the software. For purpose of simplicity, the description of a processing device is used as singular; however, one skilled in the art will appreciate that a processing device may include multiple processing elements and multiple types of processing elements. For example, the processing device may include a plurality of processors, or a single processor and a single controller. In addition, different processing configurations are possible, such as parallel processors. 
     The software may include a computer program, a piece of code, an instruction, or some combination thereof, to independently or uniformly instruct or configure the processing device to operate as desired. Software and data may be embodied permanently or temporarily in any type of machine, component, physical or virtual equipment, computer storage medium or device, or in a propagated signal wave capable of providing instructions or data to or being interpreted by the processing device. The software also may be distributed over network-coupled computer systems so that the software is stored and executed in a distributed fashion. The software and data may be stored by one or more non-transitory computer-readable recording mediums. 
     The methods according to the above-described embodiments may be recorded in non-transitory computer-readable media including program instructions to implement various operations of the above-described embodiments. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. The program instructions recorded on the media may be those specially designed and constructed for the purposes of embodiments, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of non-transitory computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROM discs and/or DVDs; magneto-optical media such as optical discs; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher-level code that may be executed by the computer using an interpreter. 
     The above-described devices may be configured to act as one or more software modules in order to perform the operations of the above-described examples, or vice versa. 
     As described above, although the embodiments have been described with reference to the limited drawings, a person skilled in the art may apply various technical modifications and variations based thereon. For example, suitable results may be achieved if the described techniques are performed in a different order and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents. While the disclosure has been illustrated and described with reference to various embodiments, it will be understood that the various embodiments are intended to be illustrative, not limiting. It will further be understood by those skilled in the art that various changes in form and detail may be made without departing from the true spirit and full scope of the disclosure, including the appended claims and their equivalents. It will also be understood that any of the embodiment(s) described herein may be used in conjunction with any other embodiment(s) described herein. 
     Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.