Patent Publication Number: US-2009228837-A1

Title: Display controller and item display method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from Japanese Patent Application Serial No. 2008-056894, filed Mar. 6, 2008, which is incorporated herein in its entirety by reference. 
     TECHNICAL FIELD 
     The invention pertains generally to a display controller and an item display method for performing processing that corresponds to a selected item when a user makes a selection while, for example, menu items or other plural items are displayed. 
     BACKGROUND 
     Japanese Kokai Patent Application No. 2002-351618 discloses a technology for selecting menu items by performing operations on a liquid crystal panel that works as a touch panel and has plural menu items displayed on it. 
     As taught therein, for example, the plural menu items for the operation of a DVD recording/playback device are displayed on a touch panel, and the user&#39;s operating location on the touch panel (the location where the user touches the touch panel) is detected. Here, a menu item selection region for recognizing the menu item is provided for each menu item. When the user&#39;s touching location is within the menu item selection region of a certain menu item, processing corresponding to the menu item is executed by the DVD recording/playback device. 
     BRIEF SUMMARY 
     According to one embodiment of the invention, plural operation items are displayed, and when a touching location on the display screen is detected, if the detected user&#39;s touching location corresponds to plural operation item selection regions on the display screen which allows selection of various operation items, processing is executed so that the operation item corresponding to a certain operation item selection region is selected according to a prescribed condition. 
     Details of this embodiment and others are described in additional detail hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein: 
         FIG. 1  is a block diagram illustrating a vehicle onboard system in which embodiments of the invention can be adopted; 
         FIG. 2  is a diagram illustrating the menu item display regions and menu item selection regions of the menu image displayed by the vehicle onboard system pertaining to Embodiment 1 of the invention; 
         FIG. 3  is a diagram illustrating the processing performed by the vehicle onboard system in Embodiment 1 in which the operated menu item is selected based on the position of the centroid of the menu item selection region; 
         FIG. 4  is a flow chart illustrating the processing performed in the vehicle onboard system pertaining to Embodiment 1 in which the operated menu item is selected based on the position of the centroid of the menu item selection region; 
         FIG. 5  is a diagram illustrating display of the user&#39;s touching location on the display screen in the vehicle onboard system pertaining to Embodiment 1; 
         FIG. 6  is a diagram illustrating the processing performed in the vehicle onboard system pertaining to Embodiment 2 of the invention in which the operated menu item is selected based on the size of the menu item selection region; 
         FIG. 7  is a flow chart illustrating the processing performed in the vehicle onboard system pertaining to Embodiment 2 in which the operated menu item is selected based on the size of the menu item selection region; 
         FIG. 8  is a diagram illustrating the vehicle onboard system pertaining to Embodiment 3 of the invention in which the menu item selection region is displayed; 
         FIG. 9  is a diagram illustrating the list display of the menu item selection region when there are overlapped menu item selection regions in the vehicle onboard system in Embodiment 4 of the invention; 
         FIG. 10  is a diagram illustrating the menu item display region and menu item selection region that tracks the user&#39;s touching location in the vehicle onboard system pertaining to Embodiment 5 of the invention; and 
         FIG. 11  is another figure illustrating the menu item display region and menu item selection region tracking the user&#39;s touching location in the vehicle onboard system pertaining to Embodiment 5. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     According to Japanese Kokai Patent Application No. 2002-351618, to prevent failure in identifying the menu item when the user&#39;s touching location corresponds to plural menu item selection regions, the image containing the menu items in the vicinity of the user&#39;s touching location is enlarged, and the user is prompted to perform the selection operation again. However, when the proportion of overlap of one menu item selection region with another menu item selection region is high, it may be impossible to select the desired menu item according to the user&#39;s touching location. 
     In contrast, embodiments of the invention taught herein provide a display controller and item display method that can ensure execution of the item desired by the user when plural items are displayed. Even when plural operation item selection regions overlap each other, it is still possible to select the operation item corresponding to a certain operation item selection region, and it is possible to execute the item desired by the user when plural items are displayed. 
     In the following, certain embodiments of the invention are explained with reference to the figures. 
     Embodiment 1 
     Embodiments of the display controller and item display method of the invention, for example, may be adopted on a vehicle onboard system pertaining with the configuration shown in  FIG. 1 . This vehicle onboard system has the following functions: a navigation function, an audio playback function for reproducing the audio signals recorded on a CD (compact disk), HDD or other recording media, or a radio broadcast program, and an image playback function for reproducing image signals recorded on a DVD (Digital Versatile Disc), HDD or other recording media. 
     This vehicle onboard system controls the display of images and various types of information on display part  2  by means of controller  1 . Also, the vehicle onboard system lets the user perform various operations by displaying menu information, including plural menu items (operation items), on display part  2 . In the following, the menu items as operation items for selection by the user are explained. However, the invention is not limited to this, and the invention also allows operations for listing information, icons, etc. 
     As the sources of the image, audio and various the types of information, the vehicle onboard system has CD playback part  3 , radio receiver  4 , TV receiver  5  as well as selector  5   a , DVD playback part  6 , HD recording/playback part  7 , navigation part  8  and GPS information receiver  8   a . Also, for the output of image, audio and various types of information, the vehicle onboard system has the following parts: distribution processing part  9  connected to parts  3 - 8 , audio processing part  10  and speaker  11 , image processing part  12  and image output part  13 . In addition, for detecting the running state of the vehicle, the vehicle onboard system has vehicle speed sensor  14  that supplies vehicle speed information and shift position sensor  15  that supplies shift position information to controller  1 . 
     Controller  1  is implemented by, for example, a microcomputer including a random access memory (RAM), a read-only memory (ROM) and a central processing unit (CPU), along with various input and output connections. Generally, processing of arithmetic and logic operations (that is, control) performed by controller  1  is performed by execution by the CPU of one or more software programs stored in ROM. Of course, some or all of the functions can be implemented by hardware components. 
     Display part  2  displays the images recorded on a DVD, TV images and an operation menu as a display screen. Display part  2  includes liquid crystal panel  21  for display of the various types of information on the display screen, and touch panel  22  made of transparent film switches or the like for detecting user operations in touching the display screen. Liquid crystal panel  21  performs operations according to the video data sent from image output part  13  in order to display the DVD or TV images. Also, according to the menu images supplied by image output part  13 , liquid crystal panel  21  displays the menu image for the operation of the various parts of the vehicle onboard system. Touch panel  22  outputs the display screen touching location information to controller  1  when a user&#39;s touching location on the display screen is detected. 
     CD playback part  3  reads CD audio data recorded on a CD and outputs them to distribution processing part  9 . Radio receiver  4  receives radio broadcast signals and outputs the radio audio data to distribution processing part  9 . TV receiver  5  receives television broadcast signals received by selector  5   a  and outputs them as TV video data to distribution processing part  9 . DVD playback part  6  reads video data recorded on a DVD and outputs them as DVD video data to distribution processing part  9 . HD recording/playback part  7  reads the signals recorded on a magnetic disk and outputs them to distribution processing part  9 , and at the same time, information sent from distribution processing part  9  is recorded on the magnetic disk. 
     HD recording/playback part  7  can also store data for the route searching map, maps and scenic spot display map for use by navigation part  8 , in addition to audio data for music, music titles and other music information data. In addition, HD recording/playback part  7  is also used for temporary storage for processing of registration location information, recommended path information and other data registered in navigation part  8 . 
     Navigation part  8  performs display of the map data stored in HD recording/playback part  7  and the current location, setting of the destination, searching for the recommended path from the current location of the vehicle to the destination set by the user with reference to the map data recorded in HD recording/playback part  7 , guidance along the recommended path, notification of traffic information, etc. Based on the current location information sent from GPS information receiver  8   a , navigation part  8  performs display of the current location and guidance along the recommended path. GPS information receiver  8   a  receives the GPS signal from GPS satellites and computes the current location information of the vehicle based on the GPS signal. 
     For example, according to the operations performed by the user on touch panel  22 , a control signal is sent from controller  1  to CD playback part  3 , radio receiver  4 , TV receiver  5 , DVD playback part  6 , HD recording/playback part  7  and navigation part  8 . As a result, operation of CD playback part  3 , radio receiver  4 , TV receiver  5 , DVD playback part  6 , HD recording/playback part  7  and navigation part  8  is performed according to the control signals. 
     Distribution processing part  9  selectively takes the data sent from CD playback part  3 , radio receiver  4 , TV receiver  5 , DVD playback part  6 , HD recording/playback part  7  or navigation part  8  as input, outputs the audio data to audio processing part  10 , and outputs the video data and menu image data to image processing part  12 . For example, distribution processing part  9  sends control signals according to the user&#39;s operations on touch panel  22 . According to the control signals, distribution processing part  9  then performs switching operations to distribute data sent from CD playback part  3 , radio receiver  4 , TV receiver  5 , DVD playback part  6 , HD recording/playback part  7  and navigation part  8 . 
     Audio processing part  10  processes the audio data fed from distribution processing part  9  and performs adjustment of the output level of the sound, adjustment of the frequency characteristics, and adjustment of the sonic field characteristics (characteristics of echo and reverberation due to display processing, etc.). Audio processing part  10  consists of a digital signal processor comprising DSP, etc. The audio processing performed by audio processing part  10  is adjusted according to a control signal from controller  1  according to user operations in adjusting the sound output level. The audio signal processed with audio processing part  10  is amplified by an amplifier (not shown in the figure), and the sound is output from speaker  11 . 
     Image processing part  12  performs various types of image processing, such as processing of video data and menu image data to adjust the hue and brightness of the displayed image, to adjust contrast, to divide or enlarge/shrink the image, to perform overlapped display of text, etc. Image processing part  12  comprises an image memory that stores the video data and menu image data, a digital processor consisting of a DSP that performs digital arithmetic and logic operations processing for the video data and menu image data stored in the image memory, VRAM (video RAM) that stores the display output image, etc. The processing performed by image processing part  12  is adjusted according to control signals from controller  1  according to user operations. 
     Image output part  13  drives liquid crystal panel  21  to display images on display part  2  based on the data stored in the VRAM of image processing part  12 . Image output part  13  comprises a converter for converting the data stored in the VRAM of image processing part  12  to the image signals for driving liquid crystal panel  21 , an amplifier, a synchronization signal generator, etc. The operation of image output part  13  is controlled by control signals from controller  1 . 
     In this way, controller  1  controls distribution processing part  9 , image processing part  12  and image output part  13 , and it works as a display control for displaying plural menu items displayed on liquid crystal panel  21  of display part  2 . 
     Controller  1  performs overall control of the various parts according to the touching location information detected by way of touch panel  22 . When CD playback part  3 , radio receiver  4 , TV receiver  5  and navigation part  8  are controlled, controller  1  reads the menu information stored beforehand in, for example, HD recording/playback part  7 , and outputs the menu image data from HD recording/playback part  7  to distribution processing part  9 . 
     The menu information stored in HD recording/playback part  7  includes plural menu items arranged in various hierarchical layers among multiple hierarchical layers and includes information for displaying plural menu items in a single image. The menu information contains menu video data having plural menu items arranged on a single screen for each hierarchical layer and coordinate information indicating the menu item selection regions that allow selection of the various menu items on touch panel  22 . In addition to the choices available for selection by the user, an OK button and a cancel button may also be included as menu items. 
     According to the control signals from controller  1 , HD recording/playback part  7  uses the menu information as references in forming the menu video data from the plural menu items. Here, menu information for the operation of CD playback part  3 , radio receiver  4 , TV receiver  5  and navigation part  8  stored in HD recording/playback part  7  becomes the coordinate information for the layout and menu item selection regions of the menu items designed corresponding to the shape or size or the like of the display image of display part  2 . Consequently, even when the menu image for the operation of CD playback part  3 , radio receiver  4 , TV receiver  5  and navigation part  8  is displayed on display part  2 , there is still no overlap between the menu item selection regions of the various menu items. 
     When the content data stored in the DVD loaded in DVD playback part  6  are to be reproduced or the like, controller  1  reads the menu information stored in the DVD by means of DVD playback part  6  and outputs the menu video data to distribution processing part  9 . Here, controller  1  allows reproduction of the content stored in the DVD only when the vehicle is stopped, as judged from the vehicle speed signal obtained from vehicle speed sensor  14  and the shift position signal obtained from shift position sensor  15 , etc. On the other hand, controller  1  prohibits reproduction of the content stored in the DVD when it is judged that the vehicle is traveling, as determined from the vehicle speed, shift position, etc. 
     Just as with the menu information stored in HD recording/playback part  7 , the menu information stored in the DVD is information that contains plural menu items and is for displaying plural menu items on the same screen. The menu information contains menu video data for the layout of plural menu items on the same screen for each hierarchical layer and coordinate information indicating the menu item selection regions that allow selection of the various menu items on touch panel  22 . In addition to the choices available for selection by the user, the menu items also include an OK button and a cancel button. 
     The menu information recorded on the DVD is designed by the person who prepared the content of the DVD. Consequently, the layout of the menu items and the width of the menu item selection regions are determined by the DVD content preparer. As a result, for the menu information of the DVD, there is no rule with respect to menu item display region  31 A or menu item selection region  31 B shown in  FIG. 2 , or menu item display region  32 A or menu item selection region  32 B. 
     More specifically,  FIG. 2  shows an example when the menu image is displayed in display part  2  for the operation of DVD playback part  6 . Menu item selection region  31 B, which is wider than menu item display region  31 A of menu item A, and menu item selection region  32 B, which is wider than menu item display region  32 A of menu item B, may overlap each other on display screen  30  of display part  2 . 
     The causes for this problem can include the facts that the menu information of the DVD has an image larger than display screen  30  of display part  2 , and the coordinate information for each menu item selection region is set assuming an image with an aspect ratio different from that of display screen  30  of display part  2 . Consequently, even when the vehicle onboard system makes use of image processing part  12  to perform contraction or other processing of the menu image data of the DVD output from DVD playback part  6 , and menu item A and menu item B are displayed in menu item display region  31 A and menu item display region  32 A such that they fit display screen  30  of liquid crystal panel  21 , there is still overlap between menu item selection region  31 B of menu item A and menu item selection region  32 B of menu item B. 
     Here, controller  1  works as follows. When the user&#39;s touching location is detected on touch panel  22  with respect to the menu item selection regions on display screen  30  that allow selection of the various menu items displayed on display screen  30  of display part  2 , if the detected user&#39;s touching location corresponds to plural menu item selection regions, processing is executed to determine the menu item corresponding to a certain menu item selection region according to a prescribed condition. In this manner, a selection function is performed. 
     More specifically, controller  1  adopts the following scheme as the prescribed condition: the menu item of the menu item selection region whose centroid has the smallest distance from the touching location is selected from among the plural menu item selection regions that contain the detected touching location on touch panel  22 . That is, as shown in  FIG. 3 , when menu item selection region  31 B of menu item A and menu item selection region  32 B of menu item B overlap each other, controller  1  compares distance D 1 , which is between centroid position  31 C of menu item selection region  31 B and touching location  33 , and distance D 2 , which is between centroid position  32 C of menu item selection region  32 B and touching location  33 . Based on this comparison, the controller  1  judges that menu item B with the shorter distance should be selected. In  FIGS. 2 and 3 , in order to facilitate explanation, menu item selection region  31 B and menu item selection region  32 B are shown as lines. In practice, however, they are not displayed in this way. 
     As shown in  FIG. 4 , controller  1  works as follows. First, in step S 1 , the touching location information is sent from touch panel  22 , and when a user operation for determining a menu item is detected on touch panel  22 , flow proceeds to step S 2 . 
     In step S 2 , controller  1  detects the touching location on display screen  30  based on the touching location information sent in step S 1 , and flow proceeds to step S 3 . 
     In step S 3 , controller  1  judges whether there are plural menu item selection regions at the touching location on display screen  30  detected in step S 2 . If there are plural menu item selection regions at the touching location, flow proceeds to step S 4 . On the other hand, if there are not plural menu items at the touching location, flow proceeds to step S 5 . 
     Here, when the menu image data are displayed on liquid crystal panel  21  of display screen  30 , controller  1  performs arithmetic and logic operations for the menu item selection region based on the layout of the various menu items and the coordinate information for the menu item selection regions in the menu image. Also, controller  1  performs arithmetic and logic operations for the positions of the centroids of the menu item selection regions based on the menu item selection regions obtained in the arithmetic and logic operations. 
     For example, as shown in  FIG. 3 , when touching location  33  is detected with respect to the overlap region between menu item selection region  31 B and menu item selection region  32 B, flow proceeds to step S 4 . 
     In step S 4 , controller  1  selects the menu item for which the position of the centroid of that menu item&#39;s selection region is nearest the user&#39;s touching location from among the menu item selection regions judged in step S 3  to be plural menu item selection regions present at the touching location. 
     Here, when the device to be operated is DVD playback part  6 , the selected menu item information is sent to DVD playback part  6 . As a result, the vehicle onboard system performs the recording/playback operation with DVD playback part  6 , or the menu image on display screen  30  can be replaced with a lower layer menu image. 
     On the other hand, in step S 5 , controller  1  selects the menu item of the menu item selection region containing the touching location. Assuming the device to be operated is navigation part  8  or the like, controller part  1  sends the selected menu item information to navigation part  8  or the like. As a result, the vehicle onboard system performs the operation desired by the user with navigation part  8  or the like, or the menu image on display screen  30  is replaced with a lower level menu image. 
     When the user performs operations on touch panel  22 , it is preferred that the vehicle onboard system display touching location  33  as shown in  FIG. 5 . When the touching location information is sent from touch panel  22 , controller  1  sends the control signals containing the supplied touching location information to image processing part  12  for overlapping display of touching location  33  in order to display the touching location. Here, image processing part  12  controls image output part  13  and liquid crystal panel  21  such that the menu image overlapped at touching location  33  is refreshed corresponding to the touching location information contained in the control signal. As a result, the vehicle onboard system can show to the user himself/herself the user&#39;s touching location recognized by the vehicle onboard system. 
     As explained in detail above, for the vehicle onboard system pertaining to Embodiment 1, when a user operation is detected on touch panel  22 , if the user&#39;s touching location corresponds to the menu item selection regions of plural menu items, it is possible to execute processing to determine the menu item corresponding to a certain menu item selection region according to a prescribed condition. As a result, according to this vehicle onboard system, even when a user operation is detected in a region where plural menu item selection regions overlap, the operation desired by the user can still be executed. 
     More specifically, for the vehicle onboard system, the menu item of the menu item selection region whose centroid has the shortest distance from the touching location is selected. Thus, even when an operation is performed in a region where the menu item selection regions overlap, the operation desired by the user can still be executed. 
     As shown in  FIG. 5 , according to this vehicle onboard system, the user&#39;s touching location on touch panel  22  is displayed on liquid crystal panel  21 . In this manner, the user touching location recognized by the vehicle onboard system can be displayed so that the user&#39;s touching location can be confirmed. 
     Embodiment 2 
     In the following, the vehicle onboard system pertaining to Embodiment 2 of the invention is explained. Parts that are the same as those in Embodiment 1 are assigned the same symbols, and their detailed explanation is not repeated. 
     For the vehicle onboard system in Embodiment 2, when the user&#39;s touching location corresponds to plural menu item selection regions displayed on the screen, controller  1  adopts the following rule. The operation item of the menu item selection region having the smallest size among the plural menu item selection regions containing the touching location is selected. That is, as shown in  FIG. 6 , assuming menu item selection region  31 B of menu item A and menu item selection region  32 B of menu item B overlap each other, controller  1  compares the size of menu item selection region  31 B to that of menu item selection region  32 B, and makes the judgment that menu item B, whose selection region is smaller, should be selected. 
     In  FIG. 6 , in order to facilitate explanation, menu item display region  31 A, menu item selection region  31 B, menu item display region  32 A and menu item selection region  32 B are shown as lines. In practice, however, they may be shown otherwise, and the contents of the menu items within menu item display region  31 A and menu item display region  32 A are displayed only by text. 
     As shown in  FIG. 7 , when it is judged that there are plural menu item selection regions at the touching location in step S 3 , flow proceeds to step S 11 , in which one menu item is selected by control part  1  based on the size of the menu item selection region. 
     In step S 11 , controller  1  selects the menu item of the menu item selection region that is smallest from among the plural menu item selection regions judged to be present at the touching location in step S 3 . Here, controller  1  predetermines the size of each menu item selection region with reference to the coordinate information of the menu item selection regions of the various menu items obtained when the menu image is displayed on liquid crystal panel  21 . 
     Here, assuming the device to be operated is DVD playback part  6 , the selected menu item information is sent to DVD playback part  6 . As a result, the vehicle onboard system performs the recording/playback operation of DVD playback part  6 , or the menu image of display screen  30  is replaced with a lower layer menu image. 
     As explained in detail above, for the vehicle onboard system in Embodiment 2, when a user operation on touch panel  22  is detected, if the user&#39;s touching location corresponds to the menu item selection regions of plural menu items, the menu item of the menu item selection region that is smallest among the plural menu item selection regions is selected. As a result, it is possible to realize the effect that the vehicle onboard system can execute the operation desired by the user even when the region of operation includes plural overlapping menu item selection regions. 
     Embodiment 3 
     In the following, the vehicle onboard system pertaining to Embodiment 3 of the invention is explained. Parts that are the same as those in the previous embodiments are assigned the same symbols, and their detailed explanation is not repeated. 
     The vehicle onboard system pertaining to Embodiment 3 differs from Embodiments 1 and 2 in that the menu item selection regions corresponding to various menu items are displayed on liquid crystal panel  21 . 
     As shown in  FIG. 8 , for this vehicle onboard system, when menu item A and menu item B are displayed, menu item selection region  31 B′ and menu item selection region  32 B′ indicated by broken lines are displayed. 
     For this vehicle onboard system, when a menu image is displayed on liquid crystal panel  21 , based on the layout of the various menu items on the menu image and the coordinate information of the menu item selection regions obtained with controller  1 , arithmetic and logic operations are performed using the coordinates of menu item selection region  31 B and menu item selection region  32 B on display screen  30 . Controller  1  then sends the coordinates of menu item selection region  31 B and menu item selection region  32 B to image processing part  12  as control signals indicating overlapping display on the menu image. Menu item selection region  31 B′ and menu item selection region  32 B′ are then displayed as shown in  FIG. 8 . 
     In this way, according to the vehicle onboard system in Embodiment 3, the menu item selection regions that allow selection of menu items are displayed to the user so that it is possible to perform the operation by avoiding the region where the menu item selection regions overlap. As a result, even when the menu item selection regions overlap each other, the vehicle onboard system still can perform the operation desired by the user. 
     For this vehicle onboard system, a scheme may be adopted such that only when it is detected that plural menu item selection regions overlap each other are menu item selection region  31 B′ and menu item selection region  32 B′ displayed. 
     Embodiment 4 
     In the following, the vehicle onboard system pertaining to Embodiment 4 of the invention is explained. Parts that are the same as those in the previous embodiments are assigned the same symbols, and their detailed explanation is not repeated. 
     For the vehicle onboard system in Embodiment 4, controller  1  enables the menu item selection regions of the plural menu items that can be selected to be displayed without overlap on liquid crystal panel  21  when the menu item selection regions corresponding to the menu items overlap each other. 
     As shown in  FIG. 9 , for this vehicle onboard system, assuming it is detected that menu item selection region  31 B of menu item A and menu item selection region  32 B of menu item B overlap on display screen  30 , operation list  34  is displayed that includes message  34   a  saying “The following menu items are selectable.” In addition, menu item selection region  34   b  of menu item A displays menu item A as text, and menu item selection region  34   c  of menu item B displays menu item B as text. Operation list  34  is displayed in a region where menu item selection region  31 B and menu item selection region  32 B do not overlap each other, if possible. 
     The display data of operation list  34  is prepared by controller  1 , and the operation list  34  is then overlapped on the menu image by means of image processing part  12 . For example, controller  1  works as follows. When the menu information of DVD playback part  6  is displayed, in a situation where menu items of the menu item selection regions that overlap each other are acquired, the display data of operation list  34  is formed as a combination of the plural menu item titles and message  34   a  and is sent to image output part  13 . Then, by means of image output part  13 , controller  1  causes operation list  34  to be displayed overlapped at a prescribed location of the menu image being displayed. Then, when operation of menu item selection regions  34   b ,  34   c  is detected at the prescribed location where operation list  34  is displayed, controller  1  judges that menu item A or menu item B has been selected by the user. 
     In this way, when a user operation is detected for a region where menu item selection region  34   b  is displayed, controller  1  recognizes that menu item A has been selected. On the other hand, when a user operation is detected for the region where menu item selection region  34   c  is displayed, it recognizes that menu item B has been selected. 
     With this vehicle onboard system, by displaying operation list  34 , it becomes possible to select the menu items from a list instead of in a region where the menu item selection regions overlap. 
     The following scheme may be adopted for controller  1  of the vehicle onboard system. When the menu item selection regions corresponding to the various menu items overlap, menu item selection regions detected as overlapping at the touching location are displayed without overlap as menu item selection regions of selectable menu items. The following scheme may also be adopted for controller  1 . When the user&#39;s touching location is judged to be a location where menu item selection region  31 B and menu item selection region  32 B overlap each other, operation list  34  containing menu item selection region  34   b  of menu item A and menu item selection region  34   c  of menu item B is displayed as shown in  FIG. 9 . 
     As a result, this vehicle onboard system makes it possible to perform reselection of menu item selection region  34   b  or menu item selection region  34   c  from operation list  34  where the menu item selection regions do not overlap, so that the desired menu item can be selected. 
     Embodiment 5 
     In the following, the vehicle onboard system pertaining to Embodiment 5 of the invention is explained. Parts that are the same as those in the previous embodiments are assigned the same symbols, and their detailed explanation is not repeated. 
     For the vehicle onboard system in Embodiment 5, when the menu item selection regions overlap each other, the menu item corresponding to the user&#39;s touching location is displayed. More specifically, as shown in  FIG. 10 , when menu item selection region  31 B and menu item selection region  32 B overlap each other, if a location contained in menu item selection region  31 B is detected as touching location  33  by controller  1 , controller  1  displays only menu item A as the menu image, while menu item display region  32 A and menu item selection region  32 B for menu item B are not displayed. 
     As shown in  FIG. 11 , for this vehicle onboard system, when the user touching location is moved from  33   a  to  33   b  inside menu item selection region  32 B of menu item B, menu item display region  31 A displayed for menu item A is no longer displayed. Also, the vehicle onboard system displays menu item display region  32 A of menu item B. 
     For this vehicle onboard system, when the menu item selection regions overlap each other, detection of touching location  33  is taken as a trigger to change the menu item. 
     The above described embodiments have been described in order to allow easy understanding of the present invention, and do not limit the present invention. On the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.