Patent Publication Number: US-2016247484-A1

Title: Method for Generating Display Frame and Terminal Device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/CN2014/090003, filed on Oct. 31, 2014, which claims priority to Chinese Patent Application No. 201310547960.5, filed on Nov. 6, 2013, both of which are hereby incorporated by reference in their entireties. 
    
    
     TECHNICAL FIELD 
     The present invention relates to the field of communications technologies, and in particular, to a method for generating a display frame and a terminal device. 
     BACKGROUND 
     In a display refreshing procedure of a terminal device such as a mobile phone on which an operating system such as an Android system is installed, a process of displaying any display frame is as follows: each application such as a desktop or flow control executes a render operation to render respective images separately, after all the applications complete the render operations, the system executes a compose operation to compose a display frame from the images rendered by the applications, for example, putting an image to the bottom and sticking an image, and output the display frame to a screen for final display. Therefore, duration of displaying a display frame mainly depends on: a maximum value among duration for the applications to execute the render operations, duration for the system to execute the compose operation, and duration of outputting the display frame to the screen. 
     A vertical synchronization (Vsync) refreshing mechanism is introduced to improve smoothness of the display frame. In the Vsync refreshing mechanism, a Vsync signal is sent to generate periodic interruption such that any render operation executed by each application or any compose operation executed by the system is triggered and activated by the Vsync signal. In this way, the entire display refreshing procedure can be performed orderly. 
     However, when a mobile phone has a hardware configuration with low performance, the duration of the render operations or the compose operation may be greater than a Vsync signal cycle. As a result, frame skipping appears, thereby reducing timeliness of display refreshing of the system. 
     SUMMARY 
     In view of this, a problem to be resolved in the present invention is how to optimize a display frame rate of a system for a terminal device to effectively improve timeliness of display refreshing. 
     To resolve the foregoing problem, according to a first aspect, the present disclosure provides a method for generating a display frame, including the following steps: when an execution result of a render operation of each application currently running on a terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition, adjusting a render execution manner of each application and a compose execution manner of the application framework layer, executing, by each application, a render operation in the adjusted render execution manner to render an image of each application, and executing, by the application framework layer, a compose operation in the adjusted compose execution manner to compose a display frame from the images of the applications. 
     With reference to the first aspect, in a first possible implementation manner, determining that an execution result of a render operation of each application currently running on the terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition includes, if a duration for the applications to execute the render operations exceeds a rendering time threshold, determining that the predetermined condition is met, or, if a quantity of consecutive times that the duration for the applications to execute the render operations exceeds a rendering time threshold exceeds a quantity of consecutive times threshold, determining that the predetermined condition is met, or, if a duration for the application framework layer to execute the compose operation exceeds a composing time threshold, determining that the predetermined condition is met, or, if a quantity of consecutive times that the duration for the application framework layer to execute the compose operation exceeds a composing time threshold exceeds the quantity of consecutive times threshold, determining that the predetermined condition is met. 
     With reference to the first aspect, in a second possible implementation manner, determining that an execution result of a render operation of each application currently running on the terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition includes, if a system frame rate during the application executing the render operation and the application framework layer executing the compose operation is lower than a frame rate threshold within a set time range, determining that the predetermined condition is met. 
     With reference to the first aspect or either one of the foregoing possible implementation manners, in a third possible implementation manner, executing, by each application, a render operation in the adjusted render execution manner includes executing, by each application, the render operation in the adjusted render execution manner according to a virtual Vsync signal, wherein the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay and executing, by the application framework layer, a compose operation in the adjusted compose execution manner includes executing, by the application framework layer, the compose operation in the compose execution manner according to the virtual Vsync signal to compose the display frame from the images of the applications. 
     With reference to the third possible implementation manner of the first aspect, in a fourth possible implementation manner, after composing a display frame from the images of the applications, the method includes sending, according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     To resolve the foregoing problem, according to a second aspect, the present disclosure provides a method for generating a display frame, including executing, by each application currently running on a terminal device, the render operation in a render execution manner according to a virtual Vsync signal to render an image of each application, wherein the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay and executing, by an application framework layer of the terminal device, a compose operation in the compose execution manner according to the virtual Vsync signal to compose a display frame from the images of the applications. 
     With reference to the second aspect, in a first possible implementation manner, after composing a display frame from the images of the applications, the method includes sending, according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     To resolve the foregoing problem, according to a third aspect, the present disclosure provides a terminal device, including an adjusting unit, configured to, when an execution result of a render operation of each application currently running on the terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition, adjust a render execution manner of each application and a compose execution manner of the application framework layer, a rendering unit, connected to the adjusting unit and configured to instruct each application to execute a render operation in the adjusted render execution manner to render an image of each application, and a composing unit, connected to the adjusting unit and configured to instruct the application framework layer to execute a compose operation in the adjusted compose execution manner to compose a display frame from the images of the applications. 
     With reference to the third aspect, in a first possible implementation manner, the terminal device further includes a determining unit, connected to the adjusting unit and configured to determine that the execution result of the render operation of each application currently running on the terminal device or the compose operation of the application framework layer of the terminal device meets the predetermined condition. The determining unit includes at least one of the following subunits: a first determining subunit, configured to determine, if a duration for the applications to execute the render operations exceeds a rendering time threshold, that the predetermined condition is met, a second determining subunit, configured to determine, if a quantity of consecutive times that duration for the applications to execute the render operations exceeds a rendering time threshold exceeds a quantity of consecutive times threshold, that the predetermined condition is met a third determining subunit, configured to determine, if duration for the application framework layer to execute the compose operation exceeds a composing time threshold, that the predetermined condition is met and a fourth determining subunit, configured to determine, if a quantity of consecutive times that duration for the application framework layer to execute the compose operation exceeds a composing time threshold exceeds quantity of consecutive times threshold, that the predetermined condition is met. 
     With reference to the first possible implementation manner of the third aspect, in a second possible implementation manner, the determining unit further includes a fifth determining subunit, configured to determine, if a system frame rate during the application executing the render operation and the application framework layer executing the compose operation is lower than a frame rate threshold within a set time range, that the predetermined condition is met. 
     With reference to the third aspect or either one of the foregoing possible implementation manners, in a third possible implementation manner, the rendering unit is further configured to instruct each application to execute the render operation in the adjusted render execution manner according to a virtual Vsync signal, wherein the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay; and the composing unit is further configured to instruct the application framework layer to execute the compose operation in the compose execution manner according to the virtual Vsync signal to compose the display frame from the images of the applications. 
     With reference to the third possible implementation manner of the third aspect, in a fourth possible implementation manner, the terminal device further includes a sending unit, connected to the composing unit and configured to send, after the display frame is composed from the images of the applications and according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     To resolve the foregoing problem, according to a fourth aspect, the present disclosure provides a terminal device, including a delayed rendering unit, configured to instruct each application currently running on the terminal device to execute the render operation in a render execution manner according to a virtual Vsync signal to render an image of each application, wherein the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay and a delayed composing unit, configured to instruct an application framework layer of the terminal device to execute a compose operation in the compose execution manner according to the virtual Vsync signal to compose a display frame from the images of the applications. 
     With reference to the fourth aspect, in a first possible implementation manner, the terminal device further includes a sending unit, connected to the delayed composing unit and configured to send, after the display frame is composed from the images of the applications and according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     According to the method for generating a display frame and the terminal device in embodiments of the present disclosure, a terminal device can control a render execution manner of each application and a compose execution manner of an application framework layer according to an execution result of a render operation of each application currently running or a compose operation of the application framework layer of the terminal device in order to reduce frame skipping caused by an improper render execution manner and an improper compose execution manner, which effectively optimizes a display frame rate of a system of the terminal device, thereby effectively improving timeliness of display refreshing of the terminal device. 
     According to the following detailed descriptions of exemplary embodiments with reference to accompanying drawings, other features and aspects of the present disclosure become clearer. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Accompanying drawings that are included in the specification and that constitute a part of the specification illustrate, along with the specification, exemplary embodiments, features, and aspects of the present disclosure, and are used to explain principles of the present disclosure. 
         FIG. 1  shows a flowchart of a method for generating a display frame according to an embodiment of the present disclosure. 
         FIG. 2  shows a schematic diagram of a display refreshing principle framework of an Android system in a method for generating a display frame according to an embodiment of the present disclosure. 
         FIG. 3  shows a schematic diagram of a Vsync display refreshing mechanism of an Android system in a method for generating a display frame according to another embodiment of the present disclosure. 
         FIG. 4  shows a schematic diagram of a case in which a processing result of a render operation meets a predetermined condition in a method for generating a display frame according to another embodiment of the present disclosure. 
         FIG. 5  shows a schematic diagram of a case in which a processing result of a compose operation meets a predetermined condition in a method for generating a display frame according to another embodiment of the present disclosure. 
         FIG. 6  shows a flowchart of a method for generating a display frame according to still another embodiment of the present disclosure. 
         FIG. 7  shows a schematic diagram of a Vsync display refreshing mechanism that is of an Android system and obtained in manner 1 in a method for generating a display frame according to still another embodiment of the present disclosure. 
         FIG. 8  shows a schematic diagram of a Vsync display refreshing mechanism that is of an Android system and obtained in manner 2 in a method for generating a display frame according to still another embodiment of the present disclosure. 
         FIG. 9  shows a flowchart of a method for generating a display frame according to an embodiment of the present disclosure. 
         FIG. 10  shows a flowchart of a method for generating a display frame according to still another embodiment of the present disclosure. 
         FIG. 11  shows a structural block diagram of a terminal device according to an embodiment of the present disclosure. 
         FIG. 12  shows a structural block diagram of a terminal device according to another embodiment of the present disclosure. 
         FIG. 13  shows a structural block diagram of a terminal device according to an embodiment of the present disclosure. 
         FIG. 14  shows a structural block diagram of a terminal device according to another embodiment of the present disclosure. 
         FIG. 15  is a schematic structural diagram of a mobile terminal according to an embodiment of the present disclosure. 
         FIG. 16  is a schematic structural diagram of another mobile terminal according to an embodiment of the present disclosure. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Various exemplary embodiments, features, and aspects of the present disclosure are described in detail in the following with reference to accompanying drawings. In the accompanying drawings, identical reference numerals denote elements that have an identical or similar function. Although various aspects of the embodiments are shown in the accompanying drawings, unless otherwise specified, the accompanying drawings are not necessarily drawn to scale. 
     The specific term “exemplary” herein means “used as an example, embodiment or illustrative”. Any embodiment described as “exemplary” herein is not necessarily interpreted as being superior to or better than other embodiments. 
     In addition, to better describe the present disclosure, many specific details are provided in the following specific implementation manners. A person skilled in the art shall understand that the present disclosure may still be implemented even without some specific details. In other instances, well-known methods, means, elements, and circuits are not specifically described, so as to highlight the subject of the present disclosure. 
     Embodiment 1 
       FIG. 1  shows a flowchart of a method for generating a display frame according to an embodiment of the present disclosure. As shown in  FIG. 1 , the method for generating a display frame includes the following steps: 
     Step S 110 : In a case in which an execution result of a render operation of each application currently running on a terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition, adjust a render execution manner of each application and a compose execution manner of the application framework layer. 
     Step S 120 : Each application executes a render operation in the adjusted render execution manner to render an image of each application. 
     Step S 130 : The application framework layer executes a compose operation in the adjusted compose execution manner to compose a display frame from the images of the applications. 
       FIG. 2  shows a schematic diagram of a display refreshing principle framework of an Android system in a method for generating a display frame according to an embodiment of the present disclosure. As shown in  FIG. 2 , the Android system is used as an example. A process from rendering an image on a terminal device such as a mobile phone by a user by using each application program (application for short) to display the image on a screen such as a liquid crystal display (LCD) screen may specifically include the following steps: 
     First, at an application layer, each application separately executes a render operation according to its own application design status, and after the render operation processing is complete, each application sends a rendered image to a server, such as the SurfaceFlinger service of the Android system, responsible for screen refreshing of an application framework layer. 
     Second, at the application framework layer, the system has three frame buffers (FBs), and the three FBs can be used cyclically. The SurfaceFlinger finds an idle FB from the three FBs, and superimposes multiple images, which are rendered by the applications, by means of a compose operation according to application configuration information. The application configured information may indicate, for example, which image should be put to the bottom, which image should be stuck, and which image uses a transparent effect in order to obtain an image finally displayed on the LCD screen, that is, a display frame. 
     Finally, at a kernel layer, a mobile display process (MDP) module may transmit the display frame through a mobile display digital interface (MDDI) to a display hardware (including a display controller and a screen), such as LCD hardware (including an LCD controller and the LCD screen), and the display frame is the image finally displayed on the screen. 
     In the Android system, the system determines a configuration policy according to hardware configuration information of the terminal device and information about each application currently running on the terminal device. For example, the system determines a render execution manner of each application and a compose execution manner of the application framework layer. At the application layer, each application may execute the render operation in the render execution manner in the configuration policy to render an image of each application, and send the rendered image to the SurfaceFlinger; at the application framework layer. The SurfaceFlinger finds the idle FB, and executes the compose operation in the compose execution manner in the configuration policy to compose the display frame from the images of the applications. At the kernel layer, the MDP module transmits the display frame to the screen to perform displaying. 
     For example, the render operation may be an operation of image rendering completed by each application on an instruction of the terminal device in response to an operation manually entering a text or a character, rendering an image, or dragging a menu, completed by the user by means of sliding on the screen. The render execution manner may be a software manner, a hardware manner, or another manner. The compose execution manner may also be a software manner, a hardware manner, or another manner. The software manner is generally implementing the render operation using an algorithm in a central processing unit (CPU) of the terminal device. The hardware manner is generally implementing the render operation using a dedicated chip in a graphic processing unit (GPU) or the MDP of the terminal device. If a hardware function of the terminal device is powerful and complex enough, more render execution manners and compose execution manners can further be provided. 
     According to the method for generating a display frame in this embodiment, a terminal device can control a render execution manner of each application and a compose execution manner of an application framework layer according to an execution result of a render operation of each application currently running or a compose operation of the application framework layer of the terminal device in order to reduce frame skipping caused by an improper render execution manner and an improper compose execution manner, which optimizes a display frame rate of a system of the terminal device, thereby improving timeliness of display refreshing of the terminal device. 
     Embodiment 2 
     A main difference between a method in this embodiment and the method shown in  FIG. 1  lies in that an application running status and a system load status are determined with reference to factors such as a duration of a render operation and a duration of a compose operation. In step S 110  of  FIG. 1 , determining that an execution result of a render operation of each application currently running on a terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition may specifically include at least one of the following cases: 
     Case 1: If a duration for the applications to execute the render operations exceeds a rendering time threshold, it is determined that the predetermined condition is met. 
     Case 2: If a quantity of consecutive times that the duration for the applications to execute the render operations exceeds a rendering time threshold exceeds a quantity of consecutive times threshold, it is determined that the predetermined condition is met. 
     Case 3: If a duration for the application framework layer to execute the compose operation exceeds a composing time threshold, it is determined that the predetermined condition is met. 
     Case 4: If a quantity of consecutive times that the duration for the application framework layer to execute the compose operation exceeds a composing time threshold exceeds a quantity of consecutive times threshold, it is determined that the predetermined condition is met. 
     A total duration used from rendering an image by each application to finally displaying the image on a screen of the terminal device (hand-following duration) depends on the duration of the render operation (render duration), the duration of the compose operation (compose duration), and a display refreshing duration. 
     The render duration is the duration of the render operation, that is, duration of rendering an image by an application. The render duration is affected by the following factors: 
     (1) A policy for rendering the image by the application. For example, the application may directly render a current image, or the image can be displayed only after some required information is acquired. For example, if a contact list needs to be displayed, current information about a contact list of a mobile phone needs to be acquired first from a database of the terminal device, and the extra time required for acquiring the information also needs to be calculated as a part of the render duration. 
     (2) A size of the image rendered by the application. For example, the application may need to render a full-screen image or modify a small icon. Generally, a larger image that needs to be rendered indicates a longer render duration. 
     (3) A manner of rendering the image by the application. The application may execute the render operation on the terminal device in a software manner (for example, using an algorithm in the CPU of the terminal device for implementation) or in a hardware manner (for example, using a dedicated chip in a GPU or an MDP of the terminal device for implementation). If the software manner is used for rendering, a CPU frequency and a current CPU load status have great impact on the render duration. If the hardware manner is used for rendering, a GPU processing capability and a current GPU load status have great impact on the render duration. In addition, one application may generally be freely installed on different mobile phones using different hardware configurations. CPU processing frequencies, GPU display processing capabilities, and the like of different mobile phones differ greatly. For a same application, an effect of rendering an image in the hardware manner may be better on some mobile phones with strong GPU processing capabilities, whereas an effect of rendering an image in the software manner may be better on some mobile phones with strong CPU capabilities and weak GPU capabilities. 
     The compose duration is a duration of superimposing multiple images by a SurfaceFlinger at the application framework layer of a system. The compose duration is affected by the following factors: 
     (1) A current processing capability and a current load status of system hardware. The system generally uses a GPU manner to execute the compose operation by default. Therefore, the GPU processing capability and a current GPU load status have great impact on the compose duration. 
     (2) A quantity of images on which the system performs the compose operation. Generally, a larger quantity of images on which the system needs to perform the compose operation indicates a longer compose duration. 
     The display refreshing duration is a duration of transferring a frame of image in an FB to a screen such as an LCD screen by a mobile phone. The display refreshing duration is affected by the following factors: 
     (1) A size of a data amount of the frame of image to be displayed on the screen. A larger size of the data amount of the frame of image to be displayed on the screen indicates a longer display refreshing duration. 
     (2) A bus transmission rate, that is, a bus transmission rate at which the MDP module transmits an image to the screen through an MDDI. A higher bus transmission rate indicates a longer display refreshing duration. 
     For a specific terminal device such as a mobile phone, display refreshing duration of a same display frame is generally fixed and usually meets a requirement of a Vsync display refreshing mechanism of an Android system, unless a manufacturer of the mobile phone uses an extremely low hardware configuration to support an LCD screen of a very large size. 
     In summary, actual render duration and actual compose duration are quite unstable due to impact from many factors, which affects a display frame rate (frame rate) of the system. 
       FIG. 3  shows a schematic diagram of a Vsync display refreshing mechanism of an Android system in a method for generating a display frame according to another embodiment of the present disclosure. As shown in  FIG. 3 , a Vsync refreshing mechanism is introduced in a Google&#39;s Jelly Bean version of the Android system. The Vsync refreshing mechanism is actually as follows: a “heartbeat”, that is, a system Vsync signal is inserted in an entire display procedure, where the Vsync signal is sent by a display controller to a CPU for generating a Vsync interrupt, so as to control each render operation and compose operation to be completed according to the heartbeat. In this way, all key steps in the entire display process are integrated into a unified Vsync management mechanism. There are two frequencies of Vsync signals: 60 hertz (Hz) and 75 Hz, which are applicable to terminal devices with different hardware configurations. If the render duration, compose duration, and display refreshing duration of each frame can all be controlled to be within a Vsync signal cycle, it can be ensured that a stability of a frame rate reaches an ideal value, thereby ensuring smoothness of the display frame. The Vsync signal cycle is a time interval at which the display controller sends a Vsync signal. 
     For example, as shown in  FIG. 3 , it is assumed that the Vsync signal cycle is T, and a signal transmission delay is not considered. After the first Vsync signal Vsync 1  arrives at the CPU, the CPU forwards the first Vsync signal Vsync 1  to each application, and each application begins to execute a render operation in response to a user&#39;s touch slide operation on a screen. Multiple images rendered by the applications are obtained after each application completes the render operation. If the render operations are completed within one Vsync signal cycle ,a remaining duration in a cycle of the Vsync signal Vsync 1  is a waiting duration. After the second Vsync signal Vsync 2  arrives at the CPU, the CPU forwards the second Vsync signal Vsync 2  to the system. The system begins to execute a compose operation to perform composing on the multiple images rendered by the applications, and a display frame is generated after the system completes the compose operation. If the compose operation is completed within one Vsync signal cycle, a remaining duration in a cycle of the Vsync signal Vsync 2  is a waiting duration. After the third Vsync signal Vsync 3  arrives at the CPU, the system begins to execute display refreshing, and finally displays the display frame on the screen. Therefore, the duration of generating the display frame is T 0 =2T. 
       FIG. 4  and  FIG. 5  show schematic diagrams of cases in which a processing result of a render operation and/or a compose operation meets a predetermined condition in a method for generating a display frame according to another embodiment of the present disclosure. It is assumed that both a rendering time threshold and a composing time threshold are one Vsync signal cycle. As shown in  FIG. 4 , in the second frame, render duration exceeds one Vsync signal cycle. As a result, frame skipping (a frame loss) appears because no display frame is displayed on a screen in a cycle of the fourth Vsync signal Vsync 4 . Similarly, as shown in  FIG. 5 , in the second frame, compose duration exceeds one Vsync signal cycle. As a result, frame skipping appears because no display frame is displayed on the screen in the cycle of the fourth Vsync signal Vsync 4 . A frame rate is reduced in both of the foregoing cases. Therefore, a frame loss can be avoided by controlling the render duration and the compose duration to be in one Vsync signal cycle, thereby ensuring the frame rate. 
     In a possible implementation manner, an application running status and a system load status are determined with reference to factors such as a set time range and a system frame rate. In step S 110  of  FIG. 1 , determining that an execution result of a render operation of each application currently running on a terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition may further include: 
     Case 5: If the system frame rate during the application executes the render operation and the application framework layer executes the compose operation is lower than a frame rate threshold within the set time range, it is determined that the predetermined condition is met. 
     Whether a current configuration policy is proper may be determined according to the frame rate. A proper frame rate needs to be obtained by performing statistics collection after a period of time, for example, after 100 to 200 frames are generated, and then the proper frame rate is compared with a set frame rate threshold. The frame rate threshold may be preset according to a hardware configuration of the terminal device. For example, if a Vsync signal frequency of the terminal device is 60 Hz, the frame rate threshold may be set to 60 frames per second. If an actual frame rate detected in this case is 59 frames per second, it is determined that a processing result of the render operations of the applications and/or the compose operation of the system meets the predetermined condition, that is, the current configuration policy is improper, and a render execution manner of the applications and/or a compose execution manner of the system need/needs to be adjusted. 
     The rendering time threshold and the composing time threshold may be separately determined according to a recommended configuration in an empirical database or a historical configuration in a historical database. The rendering time threshold may be the same as or different from the composing time threshold. 
     An empirical database may be established in the system of the terminal device. A recommended configuration may be obtained by testing various possible combinations of compose execution manners of different terminal devices and render execution manners of different applications according to hardware processing capabilities of various common terminal devices and various common applications, and the recommended configuration may be put into the empirical database. The recommended configuration may be a combination of the render execution manner of each application on the terminal device and the compose execution manner of the system. When a user starts an application, the recommended configuration may be used as a current configuration policy. 
     In addition, a historical database may further be established in the system of the terminal device. For example, on the terminal device, after each time the user starts the application and generates a display frame, if a detected frame rate is higher than the frame rate threshold, the system may automatically record a combination of a current render execution manner of the application and a current compose execution manner of the system as a historical configuration, and put the historical configuration into the historical database. When the user starts the application again, the historical configuration may be used as a current configuration policy. In this way, the current configuration policy does not need to be redetermined, thereby reducing system load. 
     Further, in an actual process of using the terminal device, an actual running status of each application and an actual load status of the system change dynamically. Therefore, the duration of the render operations and the duration of the compose operation also change dynamically. In the empirical database, allowable fluctuation ranges of the render duration of the applications and the compose duration of the system may be obtained according to results of multiple tests on the render duration of the applications and the compose duration of the system on the terminal device. 
     For example, in the empirical database or the historical database, a rendering time threshold R 0  and a composing time threshold C 0  in the recommended configuration or the historical configuration of each application may be obtained, and a fluctuation range (r 1 , r 2 ) of the render duration and a fluctuation range (c 1 , c 2 ) of the compose duration in the recommended configuration may further be obtained by performing statistics collection according to the results of the multiple tests on the render duration of the applications and the compose duration of the system on the terminal device. According to this, a render fluctuation coefficient is α 1 =(r 1 +r 2 )/2r 0 , and a compose fluctuation coefficient is α 2 =(c 1 +c 2 )/2c 0 . Therefore, an updated rendering time threshold is R=R 0 *α 1 , and an updated composing time threshold is C=C 0 *α 2 . 
     According to the method for generating a display frame in this embodiment, an application running status and a system load status are determined with reference to factors such as the duration of a render operation, the duration of a compose operation, a set time range, or a system frame rate. In this way, a render execution manner of each application and a compose execution manner of an application framework layer are adjusted, thereby effectively improving timeliness of display refreshing of a terminal device. 
     Embodiment 3 
       FIG. 6  shows a flowchart of a method for generating a display frame according to still another embodiment of the present disclosure. In  FIG. 6 , steps of which marks are the same as those in  FIG. 1  have the same functions. For brevity, detailed descriptions of these steps are omitted. As shown in  FIG. 6 , a main difference between the method shown in  FIG. 6  and the method shown in  FIG. 1  lies in that when both render duration and compose duration are less than one cycle of a system Vsync signal, a virtual Vsync signal is used to reduce hand-following duration, thereby further improving timeliness of display refreshing. 
     In detail, step S 120  may further specifically include the following step: 
     Step S 610 : Each application executes the render operation in the adjusted render execution manner according to a virtual Vsync signal, wherein the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay. 
     Accordingly, step S 130  may further specifically include the following step: 
     Step S 620 : The application framework layer executes the compose operation in the compose execution manner according to the virtual Vsync signal to compose the display frame from the images of the applications. 
     After step S 620 , the method may further include the following steps: 
     Step S 630 : Send, according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     As shown in  FIG. 3 , for some terminal devices with hardware configurations having high processing capabilities, if the render operations and the compose operation are completed far before one Vsync signal cycle ends, the remaining duration is wasted in a process of waiting for a Vsync signal to arrive. The remaining duration is also referred to as waiting duration. For example, according to a result of a test on a terminal device using a Qualcomm MSM8*30 platform, the render duration is about 6 millisecond (ms) to 8 ms, and in this case, the waiting duration after the render operations are executed within the Vsync signal cycle is about 8 ms to 10 ms. The compose duration is about 10 ms to 12 ms, and in this case, the waiting duration after the compose operation is executed within the Vsync signal cycle is about 4 ms to 6 ms. A user feels that display refreshing of the terminal device is not timely due to existence of the waiting duration. Therefore, the virtual Vsync signal may be used to improve timeliness of the display refreshing of the terminal device such that the render operations are started only after the virtual Vsync signal arrives. The virtual Vsync signal is a delayed signal obtained after the system Vsync signal experiences a set delay Δt 1 . A value of Δt 1  may be preset according to hardware configurations of different terminal devices. 
     A specific manner of executing the render operations and the compose operation according to the virtual Vsync signal in step  610  and step  620  may include the following manners: 
     Manner 1: The virtual Vsync signal triggers the render operations and the compose operation.  FIG. 7  shows a schematic diagram of manner 1 in a method for generating a display frame according to still another embodiment of the present disclosure. As shown in  FIG. 7 , it is assumed that a Vsync signal cycle is T, and a signal transmission delay is not considered. After the first Vsync signal Vsync 1  arrives at a CPU, a virtual Vsync signal Vsync- 1  is obtained after the delay Δt 1 , the CPU forwards the virtual Vsync signal Vsync- 1  to each application, and each application begins to execute a render operation in response to a user&#39;s touch slide operation on a screen. Multiple images rendered by the applications are obtained after each application completes the render operation. If the render operations are completed within one Vsync signal cycle, the remaining duration in a Vsync- 1  cycle is the waiting duration. After the second Vsync signal Vsync 2  arrives at the CPU, a virtual Vsync signal Vsync- 2  is obtained after the delay Δt 1 , the CPU forwards the virtual Vsync signal Vsync- 2  to a system, an application framework layer begins to execute a compose operation to perform composing on the multiple images rendered by the applications, and a display frame is generated after the compose operation is completed. If the compose operation is completed within one Vsync signal cycle, the remaining duration in the Vsync 2  cycle is the waiting duration. After the third Vsync signal Vsync 3  arrives at the CPU, the system begins to execute display refreshing, and finally displays the display frame on the screen. 
     The duration of generating the display frame is T 1 =2T−Δt 1 , and compared with the duration T 0  of generating the display frame in  FIG. 3 , it can be learned that T 1 &lt;T 0 . Therefore, hand-following duration is reduced in manner 1 such that the render operations can reflect a latest render operation performed by the user by means of touch sliding on the screen, thereby improving the timeliness of the display refreshing. 
     Manner 2: The virtual Vsync signal triggers render operations, and a mechanism that the virtual Vsync signal needs to be waited for to arrive between the render operations and a compose operation is cancelled such that the render operations and the compose operation can be executed continuously, thereby completing a latest render operation performed by a user by means of touch sliding on a screen. 
       FIG. 8  shows a schematic diagram of manner 2 in a method for generating a display frame according to still another embodiment of the present disclosure. As shown in  FIG. 8 , it is assumed that a Vsync signal cycle is T, and a signal transmission delay is not considered. After the first Vsync signal Vsync 1  arrives at a CPU, a virtual Vsync signal Vsync- 1  is obtained after a delay Δt 2 , the CPU forwards the Vsync- 1  signal to each application, each application begins to execute a render operation in response to a user&#39;s touch slide operation on a screen, and multiple images rendered by the applications are obtained after each application completes the render operation. In this case, a system immediately begins to execute a compose operation to perform composing on the multiple images rendered by the applications, and a display frame is generated after the system completes the compose operation. If the compose operation is completed within one Vsync signal cycle, the remaining duration in a Vsync 2  cycle is the waiting duration. After the third Vsync signal Vsync 3  arrives at the CPU, the system begins to execute display refreshing, and finally displays the display frame on the screen. The duration of generating the display frame is T 2 =2T−Δt 2 . Compared with  FIG. 3 , T 2 &lt;T 0  such that the render operations can reflect a latest render operation performed by a user by means of touch sliding on the screen, thereby improving the timeliness of the display refreshing. 
     In addition, in manner 2, because the render operations and the compose operation can be executed continuously, a value of the delay Δt 2  in manner 2 can be greater than a value of Δt 1  in manner 1 such that the render operations can reflect an updated render operation performed by the user by means of touch sliding on the screen, thereby further improving timeliness of the display refreshing. 
     According to the method for generating a display frame in this embodiment, a virtual Vsync signal obtained after a system Vsync signal is delayed is used to trigger each application to begin to execute a render operation. In this way, a hand-following duration can be effectively reduced in a case in which both render duration and compose duration are less than one cycle of the Vsync signal, thereby further improving timeliness of display refreshing of a terminal device. 
     Embodiment 4 
       FIG. 9  shows a flowchart of a method for generating a display frame according to an embodiment of the present disclosure. 
     As shown in  FIG. 9 , the method includes the following steps: 
     Step S 910 : Each application currently running on a terminal device executes the render operation in a render execution manner according to a virtual Vsync signal to render an image of each application, where the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay. 
     Step S 920 : An application framework layer of the terminal device executes a compose operation in the compose execution manner according to the virtual Vsync signal to compose a display frame from the images of the applications. 
     In a possible implementation manner, after step S 920 , the following step may further be included: 
     Step S 1010 : Send, according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     For a specific mechanism and a beneficial effect of the method for generating a display frame in this embodiment, reference may be made to  FIG. 6  to  FIG. 8  and related descriptions thereof. 
     Embodiment 5 
       FIG. 11  shows a structural block diagram of a terminal device according to an embodiment of the present disclosure. 
     As shown in  FIG. 11 , the terminal device mainly includes an adjusting unit  1110 , a rendering unit  1120 , and a composing unit  1130 . The adjusting unit  1110  is configured to in a case in which it is determined that an execution result of a render operation of each application currently running on the terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition, adjust a render execution manner of each application and a compose execution manner of the application framework layer. The rendering unit  1120  is connected to the adjusting unit  1110  and is configured to instruct each application to execute a render operation in the adjusted render execution manner to render an image of each application. The composing unit  1130  is connected to the adjusting unit  1110  and is configured to instruct the application framework layer to execute a compose operation in the adjusted compose execution manner to compose a display frame from the images of the applications. 
       FIG. 12  shows a structural block diagram of a terminal device according to another embodiment of the present disclosure. 
     As shown in  FIG. 12 , in a possible implementation manner, the terminal device further includes a determining unit  1210 , connected to the adjusting unit  1110  and configured to determine that the execution result of the render operation of each application currently running on the terminal device or the compose operation of the application framework layer of the terminal device meets the predetermined condition. The determining unit  1210  includes at least one of the following subunits: a first determining subunit  1211  configured to determine, if duration for the applications to execute the render operations exceeds a rendering time threshold, that the predetermined condition is met, a second determining subunit  1212  configured to determine, if a quantity of consecutive times that duration for the applications to execute the render operations exceeds a rendering time threshold exceeds a times threshold, that the predetermined condition is met, a third determining subunit  1213  configured to determine, if duration for the application framework layer to execute the compose operation exceeds a composing time threshold, that the predetermined condition is met. And a fourth determining subunit  1214  configured to determine, if a quantity of consecutive times that duration for the application framework layer to execute the compose operation exceeds a composing time threshold exceeds the times threshold, that the predetermined condition is met. 
     As shown in  FIG. 12 , in a possible implementation manner, the determining unit  1210  further includes a fifth determining subunit  1215  configured to determine, if a system frame rate during the application executes the render operation and the application framework layer executes the compose operation is lower than a frame rate threshold within a set time range, that the predetermined condition is met. 
     In a possible implementation manner, the rendering unit  1120  is further configured to instruct each application to execute the render operation in the adjusted render execution manner according to a virtual Vsync signal, where the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay. The composing unit  1130  is further configured to instruct the application framework layer to execute the compose operation in the compose execution manner according to the virtual Vsync signal. 
     As shown in  FIG. 12 , in a possible implementation manner, the terminal device further includes a sending unit  1220 , connected to the composing unit  1130  and configured to send, after the display frame is composed from the images of the applications and according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     For a specific mechanism and a beneficial effect for generating a display frame by the terminal device, reference may be made to  FIG. 1  to  FIG. 8  and related descriptions thereof 
     Embodiment 6 
       FIG. 13  shows a structural block diagram of a terminal device according to an embodiment of the present disclosure. 
     As shown in  FIG. 13 , the terminal device mainly includes a delayed rendering unit  1310  and a delayed composing unit  1320 . The delayed rendering unit  1310  is configured to instruct each application currently running on the terminal device to execute the render operation in a render execution manner according to a virtual Vsync signal to render an image of each application, where the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay. The delayed composing unit  1320  is configured to instruct an application framework layer of the terminal device to execute a compose operation in the compose execution manner according to the virtual Vsync signal to compose a display frame from the images of the applications. 
       FIG. 14  shows a structural block diagram of a terminal device according to another embodiment of the present disclosure. 
     As shown in  FIG. 14 , in a possible implementation manner, the terminal device further includes a sending unit  1410 , connected to the delayed composing unit  1320  and configured to send, after the display frame is composed from the images of the applications and according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     For a specific mechanism and a beneficial effect for generating a display frame by the terminal device, reference may be made to  FIG. 9  to  FIG. 10  and related descriptions thereof 
     Embodiment 7 
       FIG. 15  is a schematic structural diagram of a mobile terminal according to an embodiment of the present disclosure. The mobile terminal provided in this embodiment of the present disclosure may be configured to implement the methods implemented in the embodiments of the present disclosure shown in  FIG. 1  and  FIG. 2 . For ease of description, only a part related to the embodiments of the present disclosure is shown. For specific undisclosed technical details, reference may be made to the embodiments of the present disclosure shown in  FIG. 1  to  FIG. 8 . 
     The mobile terminal may be a terminal device such as a mobile phone, a tablet computer, a notebook computer, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA). In this embodiment of the present disclosure, an example in which the mobile terminal is a mobile phone is used for description.  FIG. 15  shows a block diagram of a partial structure, related to the embodiments of the present disclosure, of a mobile phone  300 . 
     As shown in  FIG. 15 , the mobile phone  300  includes parts such as a radio frequency (RF) circuit  320 , a memory  330 , an input unit  340 , a display unit  350 , a gravity sensor  360 , an audio frequency circuit  370 , a processor  380 , and a power supply  390 . A person skilled in the art may understand that the structure, shown in  FIG. 15 , of the mobile phone does not impose a limitation on the mobile phone, and the mobile phone may include more or less parts than those shown in the figure, or a combination of some parts, or different part arrangements. 
     The following describes the constituent parts of the mobile phone  300  in detail with reference to  FIG. 15 : 
     The RF circuit  320  may be configured to receive and transmit a signal during information reception and transmission or a call process, especially, transmit, after receiving downlink information of a base station, the downlink information to the processor  380  to perform processing; and transmit uplink data to the base station. Generally, the RF circuit includes but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, and the like. In addition, the RF circuit  320  may further communicate with a network and other devices by means of wireless communication. The wireless communication may use any communications standard or protocol, including but not limited to global system of mobile communication (GSM), general packet radio service (GPRS), code division multiple access (CDMA), wideband code division multiple access (WCDMA), long term evolution (LTE), an email, a short messaging service (SMS), and the like. 
     The memory  330  may be configured to store a software program and a module. The processor  380  executes various functional applications of the mobile phone  300  and processes data by running the software program and the module that are stored in the memory  330 . The memory  330  may mainly include a program storage area and a data storage area, where the program storage area may store an operating system, an application program required by at least one function (such as a voice playing function and an image playing function), and the like; and the data storage area may store data (such as audio data, image data, and a phone book) created according to usage of the mobile phone  300 , and the like. In addition, the memory  330  may include a high-speed random access memory and may further include a non-volatile memory, for example, at least one disk memory component, a flash memory component, or another non-volatile solid-state memory component. 
     The input unit  340  may be configured to receive entered digit or character information, and generate key signal input related to a user setting and function control of the mobile phone  300 . The input unit  340  may include a touchscreen  341  and another input device  342 . The touchscreen  341  is also referred to as a touch panel, and may collect a touch operation performed by a user on or around the touchscreen  341  (for example, an operation performed by the user on the touchscreen  341  or around the touchscreen  341  by using any suitable object or accessory such as a finger or a stylus), and drive a corresponding connecting apparatus according to a preset pattern. Optionally, the touchscreen  341  may include two parts: a touch detection apparatus and a touch controller. The touch detection apparatus detects a touch direction of the user, detects a signal generated by the touch operation, and transmits the signal to the touch controller; the touch controller receives touch information from the touch detection apparatus, converts the touch information into coordinates of a contact, and then sends the coordinates of the contact to the processor  380 , and can receive a command sent from the processor  380  and execute the command. In addition, the touchscreen  341  may be implemented in various manners such as resistive type, capacitive type, infrared type, and surface acoustic wave. In addition to the touchscreen  341 , the input unit  340  may further include the another input device  342 . The another input device  342  may include but is not limited to one or more of the following: a physical keyboard, a functional button (such as a volume control button and a power switch button), a trackball, a mouse, a joystick, and the like. 
     The display unit  350  may be configured to display information entered by the user or information provided for the user and various menus of the mobile phone  300 . The display unit  350  may include a display panel  351 . Optionally, the display panel  341  may be configured in a form such as a LCD and an organic light-emitting diode (OLED). Further, the touchscreen  341  may cover the display panel  351 . When detecting the touch operation on or around the touchscreen  341 , the touchscreen  341  transfers the touch operation to the processor  380  to determine a type of a touch event, and then the processor  380  provides corresponding visual output on the display panel  351  according to the type of the touch event. In  FIG. 15 , the touchscreen  341  and the display panel  351  are used as two independent parts to implement input and output functions of the mobile phone  300 ; however, in some embodiments, the touchscreen  341  and the display panel  351  may be integrated to implement the input and output functions of the mobile phone  300 . 
     The gravity sensor  360  may detect values of accelerations of the mobile phone in various directions (three axes generally), and detect a value and a direction of gravity when the mobile phone is in a still state, and may be configured to recognize an application of a mobile phone posture (for example, landscape-to-portrait switch, a related game, and magnetometer posture calibration), a function related to vibration recognition (such as a pedometer and a knock), and the like. 
     The mobile phone  300  may further include another sensor such as a light sensor. The light sensor may include an ambient light sensor and a proximity sensor. The ambient light sensor may adjust luminance of the display panel  341  according to lightness of ambient light; the proximity sensor may detect whether an object approaches or touches the mobile phone, and may turn off the display panel  341  and/or backlight when the mobile phone  300  moves near an ear. Other sensors such as a gyroscope, a barometer, a hygrometer, a thermometer, and an infrared sensor may further be configured on the mobile phone  300 , and details are not described herein again. 
     The audio frequency circuit  370 , a loudspeaker  371 , and a microphone  372  may provide an audio interface between the user and the mobile phone  300 . The audio frequency circuit  370  may transmit an electrical signal converted from received audio data to the loudspeaker  371 , and the loudspeaker  371  converts the electrical signal into a sound signal and outputs the sound signal; on another aspect, the microphone  372  converts a collected sound signal into an electrical signal, and the audio frequency circuit  370  receives the electrical signal and converts the electrical signal into audio data, and then outputs the audio data to the RF circuit  320  to send to, for example, another mobile phone, or outputs the audio data to the memory  330  to perform further processing. 
     The processor  380  is a control center of the mobile phone  300 , is connected to each part of the entire mobile phone through various interfaces and lines, and executes various functions of the mobile phone  300  and processes data by running or executing the software program and/or the module stored in the memory  330  or invoking the data stored in the memory  330 , thereby performing overall monitoring on the mobile phone. Optionally, the processor  380  may include one or more adjusting units. Preferably, the processor  380  may integrate an application processor and a modem processor, where the application processor mainly processes an operating system, a user interface, an application program, and the like, and the modem processor mainly processes wireless communication. It may be understood that the modem processor may also not be integrated in the processor  380 . 
     The mobile phone  300  further includes the power supply  390  (such as a battery) supplying power to each part. Preferably, the power supply may be logically connected to the processor  380  by using a power management system such that the power management system implements functions such as charging management, discharging management, and power consumption management. 
     Although not shown in the figure, the mobile phone  300  may further include a wireless fidelity (Wi-Fi) module, a Bluetooth module, and the like, and details are not described herein again. 
     In this embodiment of the present disclosure, the memory  330  is further configured to store program code including a computer operation instruction. The program may be used for adjusting a render execution manner of each application and a compose execution manner of the application framework layer in a case in which it is determined that an execution result of a render operation of each application currently running on the terminal device or a compose operation of an application framework layer of the terminal device meets a predetermined condition, instructing each application to execute a render operation in the adjusted render execution manner to render an image of each application, and instructing the application framework layer to execute a compose operation in the adjusted compose execution manner to compose a display frame from the images of the applications. 
     In a first possible implementation manner, the program may further be used for, if a duration for the applications to execute the render operations exceeds a rendering time threshold, determining that the predetermined condition is met. If a quantity of consecutive times that duration for the applications to execute the render operations exceeds a rendering time threshold exceeds a quantity of consecutive times threshold, determining that the predetermined condition is met. If a duration for the application framework layer to execute the compose operation exceeds a composing time threshold, determining that the predetermined condition is met. If a quantity of consecutive times that duration for the application framework layer to execute the compose operation exceeds a composing time threshold exceeds the quantity of consecutive times threshold, determining that the predetermined condition is met. 
     In a second possible implementation manner, the program may further be used for, if a system frame rate during the application executes the render operation and the application framework layer executes the compose operation is lower than a frame rate threshold within a set time range, determining that the predetermined condition is met. 
     In a third possible implementation manner, the program may further be used for: instructing each application to execute the render operation in the adjusted render execution manner according to a virtual Vsync signal, where the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay, and instructing the application framework layer to execute the compose operation in the compose execution manner according to the virtual Vsync signal to render the display frame from the images of the applications. 
     In a fourth possible implementation manner, the program may further be used for: sending, after the display frame is composed from the images of the applications and according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     For a specific mechanism and a beneficial effect for generating a display frame by the terminal device, reference may be made to  FIG. 1  to  FIG. 8  and related descriptions thereof 
     Embodiment 8 
       FIG. 16  is a schematic structural diagram of a mobile terminal according to an embodiment of the present disclosure. The mobile terminal provided in this embodiment of the present disclosure may be configured to implement the methods implemented in the embodiments of the present disclosure shown in  FIG. 1  and  FIG. 2 . For ease of description, only a part related to the embodiments of the present disclosure is shown. For specific undisclosed technical details, reference may be made to the embodiments of the present disclosure shown in  FIG. 9  and  FIG. 10 . 
     The mobile terminal may be a terminal device such as a mobile phone, a tablet computer, a notebook computer, an UMPC, a netbook, or a PDA. In this embodiment of the present disclosure, an example in which the mobile terminal is a mobile phone is used for description.  FIG. 16  shows a block diagram of a partial structure, related to the embodiments of the present disclosure, of a mobile phone  400 . 
     As shown in  FIG. 16 , the mobile phone  400  includes parts such as a RF circuit  420 , a memory  430 , an input unit  440 , a display unit  450 , a gravity sensor  460 , an audio frequency circuit  470 , a processor  480 , and a power supply  490 . A person skilled in the art may understand that the structure, shown in  FIG. 16 , of the mobile phone does not impose a limitation on the mobile phone, and the mobile phone may include more or less parts than those shown in the figure, or a combination of some parts, or different part arrangements. 
     The following describes the constituent parts of the mobile phone  400  in detail with reference to  FIG. 16 : 
     The RF circuit  420  may be configured to receive and transmit a signal during information reception and transmission or a call process, especially, transmit, after receiving downlink information of a base station, the downlink information to the processor  480  to perform processing; and transmit uplink data to the base station. Generally, the RF circuit includes but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a LNA, a duplexer, and the like. In addition, the RF circuit  420  may further communicate with a network and other devices by means of wireless communication. The wireless communication may use any communications standard or protocol, including but not limited to GSM, GPRS, CDMA, WCDMA, LTE, an email, a SMS, and the like. 
     The memory  430  may be configured to store a software program and a module. The processor  480  executes various functional applications of the mobile phone  400  and processes data by running the software program and the module that are stored in the memory  430 . The memory  430  may mainly include a program storage area and a data storage area, where the program storage area may store an operating system, an application program required by at least one function (such as a voice playing function and an image playing function), and the like; and the data storage area may store data (such as audio data, image data, and a phone book) created according to usage of the mobile phone  400 , and the like. In addition, the memory  430  may include a high-speed random access memory and may further include a non-volatile memory, for example, at least one disk storage component, a flash memory component, or another non-volatile solid-state memory component. 
     The input unit  440  may be configured to receive entered digit or character information, and generate key signal input related to a user setting and function control of the mobile phone  400 . The input unit  440  may include a touchscreen  441  and another input device  442 . The touchscreen  441  is also referred to as a touch panel, and may collect a touch operation performed by a user on or around the touchscreen  441  (for example, an operation performed by the user on the touchscreen  441  or around the touchscreen  441  by using any suitable object or accessory such as a finger or a stylus), and drive a corresponding connecting apparatus according to a preset pattern. Optionally, the touchscreen  441  may include two parts: a touch detection apparatus and a touch controller. The touch detection apparatus detects a touch direction of the user, detects a signal generated by the touch operation, and transmits the signal to the touch controller; the touch controller receives touch information from the touch detection apparatus, converts the touch information into coordinates of a contact, and then sends the coordinates of the contact to the processor  480 , and can receive a command from the processor  480  and execute the command. In addition, the touchscreen  441  may be implemented in various manners such as resistive type, capacitive type, infrared type, and surface acoustic wave. In addition to the touchscreen  441 , the input unit  440  may further include the another input device  442 . The another input device  442  may include but is not limited to one or more of the following: a physical keyboard, a functional button (such as a volume control button and a power switch button), a trackball, a mouse, a joystick, and the like. 
     The display unit  450  may be configured to display information entered by the user or information provided for the user and various menus of the mobile phone  400 . The display unit  450  may include a display panel  451 . Optionally, the display panel  441  may be configured in a form such as an LCD and an OLED. Further, the touchscreen  441  may cover the display panel  451 . When detecting the touch operation on or around the touchscreen  441 , the touchscreen  341  transfers the touch operation to the processor  480  to determine a type of a touch event, and then the processor  480  provides corresponding visual output on the display panel  451  according to the type of the touch event. In  FIG. 16 , the touchscreen  441  and the display panel  451  are used as two independent parts to implement input and output functions of the mobile phone  400 ; however, in some embodiments, the touchscreen  441  and the display panel  351  may be integrated to implement the input and output functions of the mobile phone  300 . 
     The gravity sensor  460  may detect values of accelerations of the mobile phone in various directions (three axes generally), and detect a value and a direction of gravity when the mobile phone is in a still state, and may be configured to recognize an application of a mobile phone posture (for example, landscape-to-portrait switch, a related game, and magnetometer posture calibration), a function related to vibration recognition (such as a pedometer and a knock), and the like. 
     The mobile phone  400  may further include another sensor such as a light sensor. Specifically, the light sensor may include an ambient light sensor and a proximity sensor. The ambient light sensor may adjust luminance of the display panel  441  according to lightness of ambient light; the proximity sensor may detect whether an object approaches or touches the mobile phone, and may shut off the display panel  441  and/or backlight when the mobile phone  400  moves near an ear. Other sensors such as a gyroscope, a barometer, a hygrometer, a thermometer, and an infrared sensor may further be configured on the mobile phone  400 , and details are not described herein again. 
     The audio frequency circuit  470 , a loudspeaker  471 , and a microphone  472  may provide an audio interface between the user and the mobile phone  400 . The audio frequency circuit  470  may transmit an electrical signal converted from received audio data to the loudspeaker  471 , and the loudspeaker  471  converts the electrical signal into a sound signal and outputs the sound signal; on another aspect, the microphone  472  converts a collected sound signal into an electrical signal, and the audio frequency circuit  470  receives the electrical signal and converts the electrical signal into audio data, and then outputs the audio data to the RF circuit  420  to send to, for example, another mobile phone, or outputs the audio data to the memory  430  to perform further processing. 
     The processor  480  is a control center of the mobile phone  400 , is connected to each part of the entire mobile phone through various interfaces and lines, and executes various functions of the mobile phone  400  and processes data by running or executing the software program and/or the module stored in the memory  430  or invoking the data stored in the memory  430 , thereby performing overall monitoring on the mobile phone. Optionally, the processor  480  may include one or more adjusting units. Preferably, the processor  480  may integrate an application processor and a modem processor, where the application processor mainly processes an operating system, a user interface, an application program, and the like, and the modem processor mainly processes wireless communication. It may be understood that the modem processor may also not be integrated in the processor  480 . 
     The mobile phone  400  further includes the power supply  490  (such as a battery) supplying power to each part. Preferably, the power supply may be logically connected to the processor  480  by using a power management system such that the power management system implements functions such as charging management, discharging management, and power consumption management. 
     Although not shown in the figure, the mobile phone  400  may further include a Wi-Fi module, a Bluetooth module, and the like, and details are not described herein again. 
     In this embodiment of the present disclosure, the memory  430  is further configured to store program code including a computer operation instruction. The program may be specifically used for instructing each application currently running on the terminal device to execute the render operation in a render execution manner according to a virtual Vsync signal to render an image of each application, where the virtual Vsync signal is a delayed signal obtained after a system Vsync signal experiences a set delay, and instructing an application framework layer of the terminal device to execute a compose operation in the compose execution manner according to the virtual Vsync signal to compose a display frame from the images of the applications. 
     In a first possible implementation manner, the program may further be used for sending, after the display frame is composed from the images of the applications and according to the first system Vsync signal after the application framework layer composes the display frame from the images of the applications, the display frame to a screen of the terminal device to perform displaying. 
     In conclusion, the foregoing descriptions are merely exemplary embodiments of the present disclosure, but are not intended to limit the protection scope of the present disclosure. Any modification, equivalent replacement, and improvement made without departing from the spirit and principle of the present disclosure shall fall within the protection scope of the present disclosure.