Abstract:
There is disclosed a device which realizes a shortcut function without providing any key exclusively used for the shortcut function. When a home key is operated in a state where a lower screen at a lower position of a hierarchical structure is displayed, a home screen at an upper position of the hierarchical structure is displayed, and data to specify the lower screen when the home key is operated are stored in association with the home key. When the home key is operated in a state where the home screen is displayed, the lower screen is displayed based on the stored data to take a shortcut to the lower screen from the home screen.

Description:
PRIORITY INFORMATION 
     This application claims priority to Japanese Patent Application No. 2009-263269, filed on Nov. 18, 2009, which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a screen display control device. More particularly, the invention relates to a device which controls screen display of a hierarchical structure. 
     2. Related Art 
     In various apparatuses, a home screen and a menu screen are usually present. Upon startup of the apparatus, the home screen is displayed as a screen of an uppermost hierarchy, and when keys are operated, various menu screens are displayed as screens of lower hierarchies. Moreover, when a home key is operated in a state where various menu screens of the lower hierarchies are displayed, the display can be returned from the screens to the home screen of the uppermost hierarchy. 
     In JP 2006-101172 A, a technology is disclosed in which when a check button of a regulation switch group is operated in a state where one of a plurality of hierarchized menu screens is displayed, the menu screen which is being displayed is stored as a shortcut menu in a memory. When a function button is depressed in a state where the menu screen is not displayed, a judgment is made as to whether or not the shortcut menu is stored in the memory. When the menu is stored, the menu screen stored in the memory is displayed. When the menu is not stored, the menu screen of the uppermost hierarchy is displayed. 
     Moreover, in JP 2007-249451 A, a technology is disclosed in which when a shortcut key is depressed, a judgment is made as to whether or not one of a plurality of sub-menu screens is being displayed. In a case where the judgment result is affirmative (the screen is being displayed), an identifier of the sub-menu screen which is being displayed is registered as a shortcut menu in a table. When the judgment result is negative (the screen is not displayed), a selection screen of the shortcut menus is displayed. 
     When a specific screen is assigned to this shortcut key and this shortcut key is depressed in a state where an arbitrary screen is displayed, the display can immediately shift to the specific screen, which improves the user&#39;s operability. However, the shortcut key needs to be newly provided in the apparatus. In recent years, the miniaturization of the apparatus and the high function thereof have further advanced, and it has been demanded that various operation keys be arranged in a limited space and that a shortcut function be realized without providing any special key such as the shortcut key. Furthermore, if a key exclusively used for the shortcut function; for example, the shortcut key or the like, is provided in the apparatus, the key is not useless for a user who does not often use the function. 
     SUMMARY 
     According to the present invention, there are provided a device and an apparatus which can simply realize a shortcut function without providing any key exclusively used for the shortcut function. 
     The present invention is a screen display control device which displays a home screen and a plurality of non-home screens of hierarchies lower than the hierarchy of the home screen, the device comprising: means for displaying the home screen, and storing an identifier to specify the non-home screen when a home key is operated in a state where the non-home screen is displayed; and means for displaying the non-home screen specified by the stored identifier when the home key is operated in a state where the home screen is displayed. 
     Moreover, according to the present invention, there is provided a screen display control device which successively displays screens of a hierarchical structure in a display unit, the device comprising: home screen display means for displaying a home screen at an upper position of the hierarchical structure, when a home key is operated in a state where a lower screen at a lower position of the hierarchical structure is displayed; storage means for associating and storing, with the home key, data to specify the lower screen when the home key is operated; and control means for displaying the lower screen based on the data stored in the storage means to take a shortcut to the lower screen from the home screen, when the home key is operated in a state where the home screen is displayed. 
     Moreover, according to the present invention, there is provided an electronic apparatus comprising: a home key; a display unit; and the above screen display control device which displays a screen in the display unit in accordance with the operation of the home key. 
     According to the present invention, the home key can also be used as a key having a shortcut function. Therefore, it is not necessary to newly provide a key exclusively used for the shortcut function. Moreover, in the present invention, the home key executes the shortcut function in the home screen, which can increase a utilization efficiency of the home key. 
     The present invention will be described by reference to the following embodiment, in order to further clarify the invention. However, the following embodiment is merely an illustration, and the scope of the present invention is not limited to the following embodiment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a constitution block diagram of an apparatus in an embodiment; 
         FIG. 2  is a plan view of an apparatus in the embodiment; 
         FIG. 3  is an explanatory view of screen transition of the embodiment; 
         FIG. 4  is an explanatory view of the screen transition of the embodiment; and 
         FIG. 5  is a processing flow chart of the embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, with reference to the drawings an embodiment of the present invention will be described with respect to a portable digital recorder serving as an example of an electronic apparatus. 
       FIG. 1  shows a constitution block diagram of a digital recorder in the present embodiment. The digital recorder comprises a flash memory  16  in which audio data encoded and compressed in an MP3 format are stored. The MP3 audio data stored in the flash memory  16  are read out by a memory controller  18  and supplied to a digital data processing circuit  22 . A device which reproduces the audio data encoded in MP3 is known as an MP3 player. 
     The digital data processing circuit  22  comprises an ROM  10 , an RAM  12 , and a CPU  14 . The CPU  14  comprises an effect processing section  59 , a digital data synthesis section  63 , an MP3 decode section  70 , and an MP3 encode section  72 . The MP3 decode section  70  and the MP3 encode section  72  may be constituted of hardware circuits for exclusive use, or of software. Moreover, the effect processing section  59  and the digital data synthesis section  63  are necessary during mixing processing, but these members are not necessarily required when voice data are simply recorded. 
     The MP3 audio data read out of the flash memory  16  by the memory controller  18  are supplied to the MP3 decode section  70  of the CPU  14 . The MP3 decode section  70  decodes the MP3 audio data to supply the data to the digital data synthesis section  63 . Decode processing in the MP3 decode section  70  is executed in accordance with an MP3 decode program included as a subroutine in a system program stored beforehand in the ROM  10 . The decoded audio data are further supplied to the digital data synthesis section  63  in response to an operation signal from an operation unit  23 . 
     Moreover, the voice data input from a directional or omnidirectional microphone provided at a predetermined position of the digital recorder are converted into digital data by an ADC  26 , and then supplied to the digital data processing circuit  22 . The CPU  14  of the digital data processing circuit  22  subjects the data to effect processing by the effect processing section  59  in response to the operation signal from the operation unit  23  to supply the data to the digital data synthesis section  63 . The digital data synthesis section  63  synthesizes the decoded audio data and the voice data subjected to the effect processing to supply the data to a DAC  27 , and the data are converted into an analog signal by the DAC  27  and output to the outside. In consequence, the MP3 audio data are synthesized with external voice data and output, whereby a user plays a musical instrument or the like in accordance with, for example, a reproduction audio signal, and the data can be mixed and reproduced. The synthesized data from the digital data synthesis section  63  may be output to the DAC  27  and supplied to the MP3 encode section  72 . When the mixing processing is not performed, the voice data input from the microphone are converted into the digital data by the ADC  26  and supplied to the MP3 encode section  72 . 
     The MP3 encode section  72  encodes the voice data or the synthesized data in the case of the mixing in an MP3 system, and the encoded data are stored in the flash memory  16 . The encode processing in the MP3 encode section  72  is executed in accordance with an MP3 encode program included as a subroutine in the system program stored beforehand in the ROM  10  in the same manner as in the MP3 decode section  70 . 
     It is to be noted that the recording of sound in the MP3 format is one example, and the sound may be recorded in another format such as a wav format. Moreover, the sound may be recorded in one of the MP3 format and the wav format in accordance with the operation of the operation unit  23  by the user. Moreover, the voice data input from the directional or omnidirectional microphone may be stereo-recorded in two channels. 
     The digital recorder can be connected to an external computer (PC) via USB, and the flash memory  16  can be accessed from the external PC via the memory controller  18 . That is, when the recorder is connected to the PC, the flash memory  16  is recognized as a USB mass storage device, and file forwarding, copying, file name change, deletion, and the like can be performed by use of the PC. 
     In a display unit  24 , various screens indicating the state of the digital recorder are displayed. Specifically, examples of the screens include a home screen as the screen of an uppermost hierarchy and various menu screens as screens of lower hierarchies. The various menu screens include a function menu screen for setting the function of the digital recorder. The user operates the operation unit  23  to display the screen necessary for the operation of the digital recorder in the display unit  24 . That is, in response to the operation signal from the operation unit  23 , the CPU  14  displays, on the display unit  24 , the screen corresponding to the operation signal in accordance with the system program stored beforehand in the ROM  10 . 
       FIG. 2  shows an appearance diagram (a plan view) of the digital recorder. In an upper part of the digital recorder, directional microphones  30 R,  30 L for stereo sound recording are provided on the left and right sides. The pair of microphones  30 R,  30 L are supported rotatably around a rotary shaft, and can be rotated in the directions indicated by arrows in the drawing. That is, the microphone  30 R can rotate as much as about 90 degrees from its illustrated position in a counterclockwise direction, and the microphone  30 L can rotate as much as about 90 degrees from its illustrated position in a clockwise direction. 
     In addition to a power switch (not shown), the operation unit  23  is provided with a rewind key  23   a , a fast forward key  23   b , a home key  23   c , a sound recording (Rec) key  23   d , a reproduction (play) key  23   e , a stop key  23   f , a function key  23   g , a setting key  23   h , a plus (+) key  23   i , and a minus (−) key  23   j.    
     The home key  23   c  is a key for displaying a home screen of an uppermost hierarchy on the display unit  24 . When the power switch of the digital recorder is turned on to start the digital recorder, the CPU  14  first displays the home screen on the display unit  24 . Moreover, when the user depresses the home key  23   c  in a state where an arbitrary lower hierarchy screen other than the home screen is displayed on the display unit  24 , the CPU  14  displays the home screen on the display unit  24  again. 
     The function key  23   g  is a key for displaying the function menu screen of the lower hierarchy on the display unit  24 . In the function menu screen, the user displays a list of various functions of the digital recorder so that the user selects an arbitrary function. A function menu includes a repeat function, a folder/file function, a reproduction speed function, a file dividing function, a file deleting function, and the like. 
     The setting key  23   h  is a key for displaying a setting menu screen of the lower hierarchy on the display unit  24 . The setting menu screen displays the ON/OFF setting of a digital recorder sound recording mode or a timer, the ON/OFF setting of a speaker, or the like. 
     In such a constitution, there is assumed a case where the user regulates a reproduction speed to a desired speed. In this case, the user starts the digital recorder to display the home screen on the display unit  24 , and then depresses the function key  23   g  to display the function menu screen. Moreover, the user selects the reproduction speed from the function menu, and regulates the parameter of the reproduction speed in a reproduction speed screen. After completing the regulation of the reproduction speed, the user depresses the home key  23   c  to display the home screen in the display unit  24 , and then depresses the reproduction key  23   e  to reproduce a desired tune. 
     On the other hand, when the user desires to regulate the reproduction speed again after reproducing the tune, in a conventional method, the user depresses the function key  23   g  in the home screen again to display the function menu screen, and then selects the reproduction speed screen to regulate the parameter, which complicates the operation. A shortcut key may be provided to assign the reproduction speed screen to the shortcut key, but the shortcut key needs to be newly provided, and it is sometimes difficult to provide the new key in the portable digital recorder having a limited size. 
     To solve the problem, in the present embodiment, the shortcut key is not newly provided, but attention is focused on the home key  23   c , and the home key  23   c  is also used as the shortcut key. That is, the home key  23   c  intrinsically has a function of shifting to the home screen when the home key is depressed in a screen other than the home screen, but the home key  23   c  is provided beforehand with a function of shifting to a screen assigned as a shortcut screen, when the key is depressed in the home screen. 
       FIGS. 3 and 4  show screen transition in the present embodiment. First, in  FIG. 3 , when the user turns on the power switch (Power ON) and the screen normally starts, a home screen (the home screen for the reproduction)  100  of the uppermost hierarchy is displayed on the display unit  24 . It is to be noted that in the home screen  100  for the reproduction started at this time, a reproduction time, a remaining time, the title of the tune which is being reproduced, and the like are displayed. 
     When the user depresses the setting key  23   h  in a state where the home screen  100  is displayed, a setting menu screen  200  is displayed on the display unit  24 . In the setting menu screen  200 , sound record setting, reproduction setting, timer setting, speaker setting, and other setting items are displayed. When the user depresses the rewind key  23   a , the setting key  23   h , or the home key  23   c  in a state where the setting menu screen  200  is displayed, the display returns to the home screen  100  again. 
     Moreover, when the user depresses the function key  23   g  in a state where the home screen  100  is displayed on the display unit  24 , a function menu screen  300  is displayed on the display unit  24 . In the function menu screen  300 , functions such as repeat, folder/file, reproduction speed, file dividing, and file deletion are displayed. When the user depresses the rewind key  23   a , the function key  23   g , or the home key  23   c  in a state where the function menu screen  300  is displayed, the display returns to the home screen again. It is to be noted that even when the user depresses the function key  23   g  in a state where the setting menu screen  200  is displayed, the function menu screen  300  is displayed. When the setting key  23   h  is depressed in a state where the function menu screen  300  is displayed, the setting menu screen  200  is displayed. 
     Moreover, when the user depresses the sound recording key  23   d  in a state where the home screen  100  is displayed on the display unit  24 , a home screen  400  for the sound recording is displayed on the display unit  24 , and the sound recording of the voice data is started. In the home screen  400  for the sound recording, a sound recording time, a sound recording level, a file name, and the like are displayed. When the user depresses the stop key  23   f  in a state where the home screen  400  for the sound recording is displayed, the display returns to the home screen  100 . 
     On the other hand, when the user depresses the power switch to start the digital recorder in a state where no card of the flash memory  16  is connected to the digital recorder, an error screen  500  is displayed on the display unit  24 . When the user connects the card of the flash memory  16  in this state, it is judged that the digital recorder normally starts, and the home screen  100  is displayed on the display unit  24 . When the user depresses the setting key  23   h  in a state where the error screen  500  is displayed, the setting menu screen  200  is displayed. On the other hand, when the user depresses the function key  23   g , an error screen  600  indicating a message “no card is connected” is displayed. 
     Next, with reference to  FIG. 4 , there will be described screen transition in a case where the home key  23   c  is also used as the shortcut key. 
     In  FIG. 4 , when the user depresses the function key  23   g  in a state where the home screen  100  is displayed, the function menu screen  300  is displayed as described above. In this state, when the user depresses the plus key  23   i  or the minus key  23   j  to arbitrarily select an item of the function menu (e.g., moves a cursor to a desired item), and depresses the fast forward key  23   b , a setting screen of the selected item; that is, one of setting screens  300 - 1  to  300 - 5  of the items, is displayed on the display unit  24 . Here, a repeat screen  300 - 1 , a folder/file screen  300 - 2 , a reproduction speed screen  300 - 3 , a file dividing screen  300 - 4 , and a file deletion screen  300 - 5  are shown. As one example, in the reproduction speed screen  300 - 3 , items of the present reproduction speed, fast, slow, and on/off are displayed. 
     When the user depresses the rewind key  23   a  in a state where this screen is displayed, the display returns to the function menu screen  300 . When the home key  23   c  is depressed, the display returns to the home screen  100 . At this time, the CPU  14  detects that the home key  23   c  has been depressed in the screen other than the home screen  100 , stores an identifier of the screen when the home key  23   c  has been depressed, and registers the shortcut screen. Specifically, the identifier of the reproduction speed screen is set to a flag for a shortcut function. 
     When the display returns to the home screen  100  and the user depresses the home key  23   c  in the home screen  100 , the CPU  14  detects that the home key  23   c  has been depressed in the home screen  100 , and refers to a value of the flag for the shortcut function so that the home key  23   c  functions as the shortcut key. Moreover, the identifier of the shortcut screen is acquired with reference to the value of the flag, and the screen specified by the identifier; that is, in this case the reproduction speed screen  300 - 3  is displayed on the display unit  24 . Therefore, when the user simply depresses the home key  23   c  in the home screen  100 , the display can immediately shift to the reproduction speed screen  300 - 3 . The home key  23   c  is intrinsically a key which functions in the screen other than the home screen  100  and which is not used in the home screen  100 . In the present embodiment, attention is focused on this concept, and the home key  23   c  is allowed to function as the shortcut key in the home screen  100 . It can be considered that the home key  23   c  in the home screen  100 , which has heretofore not been used, is allowed to function as an effective key. The home key  23   c  has an intrinsic function (of returning to the home screen  100 ) in the screen other than the home screen  100 , and is allowed to function as the shortcut. key for immediately shifting to the registered screen in the home screen  100 , whereby the shortcut function can be realized without adding any new key. Furthermore, the home key  23   c , which has not been used in the home screen  100 , can be effectively utilized. 
     It is to be noted that the flag of the shortcut function is rewritable, and is rewritten into the identifier of the latest screen, when the identifier of the screen is registered in the flag and then the home key  23   c  is depressed in another screen. For example, when the home key  23   c  is depressed in the reproduction speed screen  300 - 3 , the identifier of the reproduction speed screen  300 - 3  is registered in the flag of the shortcut function. Afterward, when the home key  23   c  is depressed in the repeat screen  300 - 1 , the identifier of the repeat screen  300 - 1  is newly registered in the flag of the shortcut key function. 
     In this way, the value of the flag can be rewritten, and hence it is assumed that when the user depresses the home key  23   c  in various screens, the screen registered as the shortcut screen becomes unclear. Therefore, when the identifier of the screen is registered in the flag of the shortcut function, a certain eye mark or mark for specifying the screen is preferably displayed beforehand on the home screen  100 . For example, in  FIG. 4 , a mark  150  of ‘S’ indicating the reproduction speed screen  300 - 3  is displayed on the home screen  100 . The user visually recognizes the home screen  100 , whereby he or she can easily recognize that the reproduction speed screen  300 - 3  is registered as the shortcut screen in the home key  23   c  at present. Needless to say, this eye mark  150  is set uniquely for each screen. The repeat screen  300 - 1  is indicated by ‘R,’ and the folder/file screen  300 - 2  is indicated by ‘F.’ 
     Moreover, the flag of the shortcut function may be stored in the RAM  12 , but can be stored in the ROM  10 . When the flag is stored in the ROM  10  and the power switch of the digital recorder is turned off, the value of the flag is retained. Next, even after the power switch is turned on, the shortcut can be realized. 
       FIG. 5  shows a processing flow chart of the present embodiment. First, when the user turns on the power switch (S 101 ), the CPU  14  displays the home screen  100  of the uppermost hierarchy in accordance with a program (S 102 ). It is to be noted that when the card of the flash memory  16  is not connected, the error screen (the screen indicating that no card is connected)  500  is displayed instead of the home screen  100  as described above. 
     When the user depresses the function key  23   g  in a state where the home screen  100  is displayed (YES in S 103 ), the CPU  14  displays the function menu screen  300  of the lower hierarchy (S 104 ). Moreover, the function item is selected by the plus key  23   i  or the minus key  23   j , and the fast forward key  23   b  is depressed to display one of the screens  300 - 1  to  300 - 5  of the respective function items (S 105 ). The user appropriately selects the screen to set the function. 
     Next, the CPU  14  judges whether or not the home key  23   c  has been depressed in these screens  300 - 1  to  300 - 5  (S 106 ). When the user depresses the home key  23   c  in, for example, the reproduction speed screen  300 - 3 , the CPU  14  sets the identifier of the reproduction speed screen  300 - 3  to a shortcut function flag Shortcut in response to this key (S 107 ). Then, the home screen  100  is displayed on the display unit  24  (S 108 ). 
     Next, the CPU  14  judges whether or not the home key  23   c  has been depressed in the home screen  100  (S 109 ). When the user depresses the home key  23   c , the CPU  14  displays the screen specified by the identifier set to this flag (in this case, the reproduction speed screen  300 - 3 ) with reference to the value of the flag Shortcut in response to this key (S 110 ). It is to be noted that the identifier of the home screen  100  is set as a default to the flag Shortcut, whereby, when the home key  23   c  is depressed in the home screen  100  (S 102 ) just after the start, the home screen  100  continues to be displayed. 
     It is to be noted that after the home key  23   c  is depressed in the home screen  100  to immediately shift to the reproduction speed screen  300 - 3 , the user shifts to another screen, such as the repeat screen  300 - 1 , and depresses the home key  23   c  in the repeat screen  300 - 1 . In response to the key, the CPU  14  newly sets the identifier of the repeat screen  300 - 1  to the flag Shortcut. That is, the value of the flag Shortcut is overwritten. Therefore, when the user depresses the home key  23   c  in the home screen  100  again after shifting to the home screen  100 , the display does not shift to the reproduction speed screen  300 - 3 , but shifts to the repeat screen  300 - 1 . 
     In this way, according to the present embodiment, when the home key  23   c  is depressed, this depressing is regarded as a trigger to automatically register the screen when the home key  23   c  is depressed as the shortcut screen, which obviates the need for a separate key for registering the shortcut screen. Moreover, when the home key  23   c  is depressed in the home screen  100 , the display immediately shifts to the already registered screen, which obviates the need for a separate key for executing the shortcut. Furthermore, the home key  23   c , which is intrinsically not used in the home screen  100 , is allowed to function as the shortcut key, whereby the home key  23   c  can be effectively utilized. It is to be noted that in the present embodiment, the home key  23   c  has three functions: 
     (1) a function of returning to the home screen  100 ; 
     (2) a function of registering the shortcut screen; and 
     (3) a function of executing the shortcut. 
     The embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and various alterations can be achieved. For example, in the present embodiment, the digital recorder has been described as an example of the apparatus, but the apparatus is not limited to the digital recorder, and the present invention can be applied to an audio device, an information apparatus, a terminal apparatus, a communication apparatus, and the like. Moreover, in the present embodiment, the home key  23   c  is a key which can be depressed, but the type of the key is arbitrary, and a touch switch or the like may be used. 
     Moreover, in the present embodiment, the value of the flag Shortcut can be rewritten (can be overwritten), but a plurality of identifiers may be set. For example, two identifiers; that is, the previous identifier and the present identifier, can be set. In this case, when the home key  23   c  is depressed once in the home screen  100 , the display shifts to a screen registered just before. When the home key  23   c  is depressed continuously twice (double clicked), the display can shift to a screen registered before the previous screen. 
     Furthermore, in the present embodiment, the identifier is set to the flag Shortcut, but the identifier is one example of information for specifying the screen, and arbitrary data for uniquely specifying the screen below the home screen  100  in the hierarchical structure can be set to the flag. Moreover, the flag is not necessarily essential. In short, data for uniquely specifying the screen below the home screen  100  in the hierarchical structure in association with the home key  23   c  may be stored in the ROM  10  or the RAM  12 .