Abstract:
An apparatus and a method for inputting a function key. The apparatus and method provide convenience with which a user can use function keys of a QWERTY-type keyboard, such as direction keys and cursor movement keys, in a small-sized terminal. Also, the apparatus and method enable easy input of various function keys, and can thus increase the efficiency of inputting the function keys.

Description:
PRIORITY 
       [0001]    This application claims priority under 35 U.S.C. §119(a) to an application filed in the Korean Industrial Property Office on Aug. 23, 2007 and assigned Serial No. 2007-84942, the contents of which are hereby incorporated by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention generally relates to a terminal equipped with a touch-screen, and more particularly to an apparatus and method for inputting a function key. 
         [0004]    2. Description of the Related Art 
         [0005]    Recently, mobile communication terminals, including cell phones, Personal Digital Assistants (PDAs), etc., equipped with standard QWERTY-type keypads for computer keyboards have appeared. Accordingly, a user has convenience in that he/she can easily input a key by using a relevant terminal in the same manner as when he/she uses a computer. 
         [0006]    Meanwhile, a user moves a location of a cursor and edits characters usually in a character editing mode. The cursor is generally a small symbol indicating a location for modifying or inputting a particular character, and is usually displayed as a blinking underline or an inverted square. Accordingly, when editing characters, the user can designate a location for editing, moving the location of the cursor. 
         [0007]    In order to move the location of the cursor, the user uses direction keys or cursor movement keys in a QWERTY-type keyboard. The direction keys include an upward (↑) key, a downward (↓) key, a leftward (←) key and a rightward (→) key, and are used to move the cursor in upward, downward, leftward, and rightward directions, respectively. Also, the cursor movement keys include a Page Up key, a Page Down key, a Home key and an End key. Among them, the Page Up key is used to move the cursor upward by one page, whereas the Page Down key is used to move the cursor downward by one page. Also, the Home page is used to move the cursor to the beginning of a sentence or a document, whereas the End key is used to move the cursor to the end of a sentence or a document. Accordingly, in the character mode, the user can more easily edit characters when he/she uses the direction keys and the cursor movement keys. 
         [0008]    A conventional QWERTY-type keyboard is normally equipped with function keys, such as direction keys and cursor movement keys for moving a location of a cursor. However, since function keys as described above are implemented as separate keys in conventional keyboards, when a user intends to input a desired function key, there is inconvenience in that he/she must select a relevant function key from among the function keys. Moreover, when a QWERTY-type keypad is intended to be applied to a mobile communication terminal, the application has difficulties in implementing all keys according to the layout of the QWERTY-type keyboard in the terminal which is getting smaller. 
         [0009]    Due to the above-described problems, a need exists for a method capable of efficiently configuring a keypad and providing more various function keys. 
       SUMMARY OF THE INVENTION 
       [0010]    Accordingly, the present invention substantially solves the above-described problems occurring in the prior art, and provides an apparatus and a method for more conveniently inputting each function key by efficiently displaying the function keys, such as direction keys and cursor movement keys, on a touch-screen of a terminal. 
         [0011]    In accordance with an aspect of the present invention, there is provided a method for inputting a function key in a terminal equipped with a touch-screen, the method including determining whether a Press event occurs in a function key area enabling selective use of any direction keys and cursor movement keys; when the Press event occurs, respectively assigning any of the direction keys and the cursor movement keys to key areas, and displaying the keys respectively assigned to the key areas; and when a Release event occurs in the function key area, releasing the assignment of the displayed keys to restore each of the key areas to a display state that was present before the occurrence of the Press event, and displaying the restored key areas. 
         [0012]    In accordance with another aspect of the present invention, there is provided an apparatus for inputting a function key, the apparatus including a touch-screen for outputting a character received as an input, displaying a function key area enabling selective use of any direction keys and cursor movement keys, and generating any of a Press event, a Release event, and a Drag event in response to an input of a user; a memory for storing therein functions respectively corresponding to the direction keys and the cursor movement keys; and a control unit for controlling the touch-screen to display the function key area on the touch-screen, respectively assigning any of the direction keys and the cursor movement keys to key areas and displaying the keys respectively assigned to the key areas when the Press event occurs in the function key area, and releasing the assignment of the displayed keys to restore each of the key areas to a display state that was present before the occurrence of the Press event and displaying the restored key areas when the Release event occurs in the function key area. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The above and other features, aspects, and advantages of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
           [0014]      FIG. 1  is a block diagram illustrating a configuration of a terminal providing function keys according to the present invention; 
           [0015]      FIG. 2  an illustrative view showing a keypad displayed on a touch-screen according to the present invention; 
           [0016]      FIGS. 3(   a ) and  3 ( b ) are illustrative views showing direction keys and cursor movement keys respectively displayed in key areas according to the present invention; 
           [0017]      FIG. 4  is a flowchart illustrating a control process of selecting the direction keys in character editing mode according to the present invention; 
           [0018]      FIG. 5  is a flowchart illustrating a control process of selecting the cursor movement keys in the character editing mode according to the present invention; 
           [0019]      FIG. 6  is a flowchart illustrating a control process of displaying the direction keys or the cursor movement keys based on a touch input time in the character editing mode according to the present invention; 
           [0020]      FIG. 7  are illustrative views showing a selection process of a Select key according to the present invention; and 
           [0021]      FIGS. 8(   a ) and  8 ( b ) are illustrative views showing a selection process of a Lock key according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. 
         [0023]    The present invention provides an apparatus and a method for inputting a function key. To this end, a terminal equipped with a touch-screen according to the present invention determines whether a Press event occurs in a function key area enabling selective use of either direction keys or cursor movement keys. When a Press event occurs, the terminal respectively assigns any of the direction keys and cursor movement keys to key areas, and displays the keys respectively assigned to the key areas. When a Release event occurs in the function key area, the terminal releases the assignment of the displayed keys to restore each of the key areas to a display state that was present before the occurrence of the Press event, and displays the restored key areas. Accordingly, the present invention provides convenience in that a user can use more function keys in the terminal, and can easily select various function keys. 
         [0024]    A description will now be made of a configuration of a terminal providing function keys according to an embodiment of the present invention with reference to  FIG. 1 . 
         [0025]    Referring to  FIG. 1 , the terminal providing the function keys includes a Radio Frequency (RF) unit  100 , a memory unit  110 , a touch-screen  120 , and a control unit  130 . 
         [0026]    The RF unit  100  performs a radio communication function of the terminal. The memory unit  110  includes a Read Only Memory (ROM) and a Random Access Memory (RAM) for storing multiple programs and data therein. Particularly, the memory  110  stores therein, for example, Hangul, English, numerals, special characters, etc., referred to herein as “characters”, displayed in character areas of the touch-screen  120  for a keypad function according to the present invention. Also, the memory  110  stores therein functions respectively corresponding to the direction keys and the cursor movement keys corresponding to the function keys according to the present invention. The direction keys include at least one of an upward (↑) key, a downward (↓) key, a leftward (←) key, and a rightward (→) key. The cursor movement keys include at least one of a Page Up key, a Page Down key, a Home key, and an End key. 
         [0027]    The touch-screen  120  is a display which can detect a location of touch when a human hand or an object touches a character or a particular location displayed on a screen thereof, and can then perform particular processing by using stored software. The touch-screen  120  receives touch input from a user and displays expression data under the control of the control unit  130 , or displays an operation state of the terminal and multiple pieces of information as icons and characters. Particularly, the touch-screen  120  to which the present invention is applied displays character areas for character input and an input editor window for editing input characters under the control of the control unit  130 . Also, in a character editing mode, the touch-screen  120  outputs a character received as input through the character area to the input editor window, and displays a cursor indicating a location for editing along with the output character. 
         [0028]    Meanwhile, the touch-screen  120  displays a function key area enabling selective use of any of the direction keys and the cursor movement keys, and generates a Press event in response to the input of the user. Also, the touch-screen  120  generates a Release event and a Drag event in response to the input of the user in each of the key areas which respectively display the direction keys or the cursor movement keys. The Press event occurs when a particular key area is pressed, and the Release event occurs when the pressing of the particular key area is released. Also, the Drag event occurs when a Drag input is received from the user in the key areas displayed on the touch-screen  120 . Accordingly, the user can easily input a desired function key in the input scheme as described above. 
         [0029]    The control unit  130  performs an overall control operation of the terminal. Also, according to the present invention, the control unit  130  determines whether a Press event occurs in a function key area. When it is determined that a Press event occurs, the control unit  130  respectively assigns any of the direction keys and cursor movement keys to the key areas, and displays the keys respectively assigned to the key areas. When a Release event occurs in the function key area, the control unit  130  releases the assignment of the direction keys or the cursor movement keys, respectively displayed in the key areas. The release of the assignment is performed so that the control unit  130  may restore each of the key areas to a display state that was present before the occurrence of the Press event and display the restored key areas. 
         [0030]    Meanwhile, if a Press event occurs again in a state of restoring the key areas to display the restored key areas, the control unit  130  respectively displays, in the key areas, keys different from the keys previously displayed in the key areas among the direction keys and the cursor movement keys. For example, if the direction keys are first displayed in response to the occurrence of the Press event, the cursor movement keys are displayed in response to the next occurrence of a Press event. Accordingly, the present invention provides the user with convenience in that he/she can selectively use the direction keys or the cursor movement keys when editing characters. 
         [0031]    A description will now be made of a keypad displayed on the touch-screen according to the present invention with reference to  FIG. 2 . 
         [0032]    Referring to  FIG. 2 , multiple characters are displayed in a QWERTY format in each character area in the keypad. Also, several editing keys used when inputting characters are displayed in the key areas on the right side of the character areas. The following description will be made of a function key area  200  enabling selective use of the function keys, such as the direction keys and the cursor movement keys, among the displayed editing keys according to the present invention. 
         [0033]    Referring to  FIG. 2 , an identifier indicating usable keys of either the direction keys or the cursor movement keys is displayed in the function key area  200 . Accordingly, when an identifier indicating that it is possible to use the direction keys is displayed in the unction key area  200 , the user can select and use each of upward (T), downward (↓), leftward (←), and rightward (→) direction keys displayed as illustrated via function key area  300  in  FIG. 3(   a ). Other than this, when an identifier indicating the use of the cursor movement keys is displayed in the function key area  200 , the user can select and use each of the cursor movement keys, including Page Up, Page Down, Home, and End keys, displayed as illustrated via function key area  310  in  FIG. 3(   b ). As described above, in the present invention, the user views the identifier displayed in the function key area  200  of  FIG. 2 , and can recognize currently usable keys among the direction keys and the cursor movement keys. 
         [0034]    A description will now be made of a control process of selecting the direction keys in a character editing mode according to the present invention with reference to  FIG. 4 . 
         [0035]    Referring to  FIG. 4 , the description is made taking, as an example, a case of displaying the identifier indicating that it is possible to use the direction keys, referred to herein as the “direction key identifier”, in the function key area. 
         [0036]    Accordingly, while performing the character editing mode, the control unit  130  determines in step  400  whether a Press event occurs in the function key area displaying the direction key identifier. If it is determined that a Press event occurs, the control unit  130  proceeds to step  402 , respectively assigns the direction keys to the key areas, and displays the direction keys respectively assigned to the key areas. Accordingly, the direction keys are displayed as illustrated in  FIG. 3(   a ). 
         [0037]    Namely, when the Press event occurs in the function key area  300  of  FIG. 3(   a ) displaying the direction key identifier, each of the upward (↑), downward (↓), leftward (←), and rightward (→) direction keys is displayed in the relevant key area located in each direction, centering on the function key area  300  where the Press event occurs. According to the present invention, the direction keys can be displayed in either two or more character areas respectively assigned at least one character for character input, a pop-up window, or others. Namely, the direction keys may be displayed instead of key items or characters in all of the key areas displayed on the touch-screen  120 , and may be displayed in a newly generated pop-up window. According to the present invention, it may be possible to change a display scheme of the direction keys in various forms. 
         [0038]    In a state of displaying the direction keys as described above, the control unit  130  proceeds to step  404 , and determines whether a Drag event or a Release event occurs. If it is determined that a Drag event occurs, the control unit  130  proceeds to step  406 , and directs any of the direction keys in response to the Drag event. If it is determined in step  408  that a Release event occurs, the control unit  130  proceeds to step  410 , and moves a cursor in a relevant direction of the directed direction key. 
         [0039]    Specifically, referring to  FIG. 3(   a ), if the direction keys are assigned to the key areas and displayed in the key areas, respectively, the control unit  130  determines whether a Drag event occurs. If it is determined that a Drag event occurs, the control unit  130  directs any of the direction keys in a direction of the Drag event. When it is determined that a Release event occurs in a directed direction key area, the control unit  130  moves the cursor in a particular direction corresponding to the directed direction key. For example, if a Release event occurs in an area (i.e. a direction key area) displaying the rightward (→) direction key from among the upward (↑), downward (↓), leftward (←), and rightward (→) direction keys, the control unit  130  moves the cursor sideways by a character in the right direction. 
         [0040]    Meanwhile, if it is determined in step  404  that a Release event occurs, the control unit  130  proceeds to step  412 . In step  412 , the control unit  130  displays an identifier indicating that it is possible to use the cursor movement keys, referred to herein as a “cursor movement key identifier”, instead of the direction key identifier in the function key area. At this time, the control unit  130  releases the assignment of the upward (↑), downward (↓), leftward (←), and rightward (→) direction keys, which are assigned to the key areas and displayed in the key areas, respectively. Then, the control unit  130  restores each of the relevant key areas to a display state that was present before the occurrence of the Press event in the function key area. For example, if the leftward (←) direction key is assigned instead of “JKL” to a character area displaying “JKL”, and is displayed in the character area, the control unit  130  releases the assignment of the leftward (←) direction key, and then displays “JKL” again. Accordingly, a user has convenience with which he/she can input a direction key and can then continue to input characters. 
         [0041]    In the present invention, when a Release event occurs immediately after the occurrence of a Press event in the function key area displaying the direction key identifier, the control unit  130  displays the cursor movement key identifier in the function key area so that the user can use the cursor movement keys instead of the direction keys. Namely, the control unit  130  changes an identifier displayed in the function key area from the direction key identifier to the cursor movement key identifier, thereby informing the user that the use of the cursor movement keys is designated. In order to determine whether the cursor movement keys are used, the control unit  130  proceeds from step  412  to the next step. In  FIG. 4 , a symbol “A” representing a step following step  412  is used in order to show that step  412  as illustrated in  FIG. 4  may be connected to step  500  as illustrated in  FIG. 5 . 
         [0042]    Steps following step  412  will now be described referring to  FIG. 5 , which illustrates a control process of selecting the cursor movement keys in the character editing mode according to the present invention. 
         [0043]    Referring to  FIG. 5 , the control unit  130  determines in step  500  whether a Press event occurs in a function key area displaying the cursor movement key identifier. If it is determined that a Press event occurs, the control unit  130  proceeds to step  502 , respectively assigns the cursor movement keys to the key areas, and displays the cursor movement keys respectively assigned to the key areas. Namely, when a Press event occurs in a function key area  310  displaying the cursor movement key identifier, the control unit  130  displays each of the Page Up, Page Down, Home, and End keys corresponding to the cursor movement keys in a key area located in each direction, centering on the function key area  310  where the Press event occurs, as illustrated in  FIG. 3(   b ). 
         [0044]    In a state where the cursor movement keys are displayed as described above, the control unit  130  proceeds to step  504 , and determines whether a Drag event or a Release event occurs. If it is determined that a Drag event occurs, the control unit  130  proceeds to step  506 , and directs any of the cursor movement keys in response to the Drag event. When it is determined in step  508  that a Release event occurs, the control unit  130  proceeds to step  510 , and moves the cursor in a relevant direction of the directed cursor movement key. In other words, the control unit  130  moves a location of the cursor either on a sentence-by-sentence basis or on a page-by-page basis in a particular direction corresponding to the directed cursor movement key. As described above, a process of selecting the cursor movement keys is similar to the process of selecting the direction keys. Accordingly, when the cursor movement keys are respectively displayed in the key areas, the user selects a desired one of the cursor movement keys through a Drag event, and generates a Release event, so that he/she can perform a function corresponding to the relevant cursor movement key. 
         [0045]    Meanwhile, when it is determined in step  504  that a Release event occurs, the control unit  130  proceeds to step  512 , and displays the direction key identifier instead of the cursor movement key identifier in the function key area. Namely, when a Release event occurs immediately after the Press event occurs in the function key area, in a toggle scheme, the control unit  130  changes an identifier from the cursor movement key identifier to the direction key identifier, and displays the changed direction key identifier. Accordingly,  FIG. 5  illustrates all steps in such a manner that they are completed, but the control unit  130  returns to step  400  and repeats the steps as described above. Accordingly, the user has convenience in that he/she can more conveniently select and use either the direction keys or the cursor movement keys through the process as described above. 
         [0046]    In another embodiment of the present invention, by selecting a direction of a Drag event differently from the embodiment as described above, a user can input the direction keys or the cursor movement keys. Specifically, the control unit  130  determines whether a Drag event occurs when a Press event occurs in the function key area displaying the direction key identifier or the cursor movement key identifier. At this time, even though a Press event occurs, the control unit  130  does not display the direction keys or the cursor movement keys. Accordingly, the control unit  130  can separately display relevant information so that the user can recognize which key corresponds to each direction in either the direction keys or the cursor movement keys along with the identifier in the function key area. 
         [0047]    Meanwhile, according to another embodiment of the present invention, if it is determined that a Drag event occurs, the control unit  130  detects a direction of the Drag event, centering on the function key area. Then, the control unit  130  identifies a key corresponding to the detected direction among either the direction keys or the cursor movement keys, and performs a function corresponding to the identified key when a Release event occurs. Namely, when the identified key is a direction key, the control unit  130  moves a location of a cursor on a character-by-character basis. Other than this, when the identified key is a cursor movement key, the control unit  130  moves the location of the cursor either on a sentence-by-sentence basis or on a page-by-page basis. Through the method as described above, the user can save time used to input a function key. 
         [0048]    In the two embodiments as described above, the control unit  130  selectively displays either the direction keys or the cursor movement keys based on whether there exists a Drag event. Also, the control unit  130  may display the direction keys or the cursor movement keys based on a duration time of a Press event in the function key area. A description of this will now be made referring to  FIG. 6 , which illustrates a control process of displaying the direction keys or the cursor movement keys based on a touch input time in the character editing mode according to of the present invention. 
         [0049]    Referring to  FIG. 6 , while performing the character editing mode, the control unit  130  determines in step  600  whether a Press event occurs in the function key area displaying the direction key identifier. When it is determined that a Press event occurs, the control unit  130  proceeds to step  602 , and measures a touch input time. According to this embodiment of the present invention, the term “touch input time” refers to an elapsed time from a time point of the occurrence of a Press event in the function key area. The touch input time is used as reference for selective display of either the direction keys or the cursor movement keys shown in  FIG. 6 . 
         [0050]    Accordingly, the control unit  130  compares a touch input time with a critical time, and determines whether a Release event occurs within the critical time. If it is determined that a Release event does not occur, the control unit  130  proceeds to step  606 , respectively assigns the direction keys to the key areas, and displays the direction keys respectively assigned to the key areas. When it is determined in step  608  that a Drag event occurs, the control unit  130  proceeds to step  610 , and directs any of the direction keys in response to the Drag event. Then, the control unit  130  determines in step  612  whether a Release event occurs in an area displaying the directed direction key. If it is determined that a Release event occurs, the control unit proceeds to step  614 , and moves a cursor in a relevant direction of the directed direction key. 
         [0051]    Meanwhile, when it is determined in step  604  that the Release event occurs within the critical time, the control unit  130  proceeds to step  616 , and displays the cursor movement key identifier instead of the direction key identifier in the function key area. After the cursor movement key identifier is displayed in the function key area, the control unit  130  may change the cursor movement key identifier to the direction key identifier and display the changed direction key identifier, in response to the touch input time, as described above. 
         [0052]    In  FIG. 6 , if a time when a Press event occurs in the function key area exceeds the critical time, the control unit  130  respectively assigns either the direction keys or the cursor movement keys to the key areas and displays the relevant keys respectively assigned to the key areas, in response to an identifier displayed in the function key area. On the contrary, if a time when a Press event occurs in the function key area does not exceed the critical time, the control unit  130  changes an identifier displayed in the function key area from the direction key identifier to the cursor movement key identifier or vice versa. 
         [0053]    As described above, the present invention provides a method for inputting the function keys, such as the direction keys and the cursor movement keys, in various ways, and accordingly, provides the advantages that the convenience of the user increases and the user can use more function keys even in a small-sized terminal. 
         [0054]    Meanwhile, in order to more easily use the function keys as described above, the present invention additionally provides a Select key and a Lock key. According to the present invention, the Select key is used to specify characters output in the input editor window on a block-by-block basis. When a Press event occurs in the function key area  700  displaying the cursor movement key identifier as illustrated in  FIG. 7 , the Select key  710  is additionally assigned to a relevant key area along with the cursor movement keys, and is displayed in the relevant key area. This is also the same when the direction keys are simultaneously displayed while the direction key identifier is displayed in the function key area  700 . Accordingly, the user directs the Select key  710  through a Drag event and then generates a Release event, so that he/she can specify characters on a block-by-block basis. 
         [0055]    In the same manner as the Select key, the Lock key is assigned to a relevant key, area along with the direction keys or the cursor movement keys, and is displayed in the relevant key area. The Lock key is used so that the direction keys or the cursor movement keys may continue to be displayed even after a Release event occurs. A description of the Lock key as described above will be made as follows referring to  FIGS. 8(   a ) and  8 ( b ).  FIG. 8(   a ) shows that the Lock key  810  is displayed along with the cursor movement keys. Hence, the user generates a Press event in the function key area  800  and then selects an area (i.e. a Lock key area) displaying the Lock key  810  through a Drag event. Then, the user generates a Release event in the Lock key area, so that the cursor movement keys respectively displayed in the key areas can be fixedly displayed. At this time, according to the present invention, the Lock key area as described above can be changed to an area (i.e. an Unlock key area) displaying an Unlock key  820 , and the Unlock key can then be displayed in the Unlock key area, as illustrated in  FIG. 8(   b ). For this reason, when the user intends to release the function of fixedly displaying the cursor movement keys, he/she selects the Unlock key  820 , so that he/she can input each of the cursor movement keys in the original way. Similarly to this, after the Select key is input by the user, the Select key may also be changed to an Unselect key, and the Unlock key is displayed in the relevant key area. Hence, the user has convenience in that he/she can more conveniently input the direction keys and the cursor movement keys by using the Select and Lock keys. 
         [0056]    While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Therefore, the spirit and scope of the present invention should be understood to be defined not by described embodiments thereof but by the appended claims and equivalents of the appended claims.