Abstract:
System and methods are provided that permit the operating state of a software application to be controlled with a single button on a keyboard. Data may be stored that associate the application&#39;s operating states with predetermined successor states. In response to operation of the key, the current operating state of the application is identified, a corresponding successor state is identified, and the application is placed in the successor states. This arrangement reduces reliance on a mouse to select menu commands or the need to memorize keyboard equivalents and reduces the complexity of keyboards.

Description:
[0001]    This non-provisional application claims benefit of Canadian Application 2,573,914 which was filed on Jan. 12, 2007. 
       FIELD OF THE INVENTION 
       [0002]    The invention relates generally to computing devices, and more specifically, to system and method for controlling the operating states of an application. 
       BACKGROUND 
       [0003]      FIGS. 1   a - d  depict simulated screen shots of Windows XP™. Applications that are compliant with the Windows XP™ operating system have certain operating states in common, namely, a non-operative state, a foreground state, a background state, and a minimized state. In a non-operative state, an application typically resides in a storage device, such as a hard disc drive, and has not been launched. In a foreground state, as exemplified in  FIG. 1   a , an application has an open window  10 , which may overlay and obscure windows associated with other applications, such as the window  11 . Most significantly, in the foreground state, keystrokes and mouse clicks are directed to the application for processing. In a background state of operation, as exemplified in  FIG. 1   b , windows associated with other applications, such as the window  11 , may overlay the application&#39;s window  10 . The menu bar associated with the application&#39;s window  10  is then dimmed (not shown) to suggest an inactive state, and keystrokes, mouse clicks and, more generally, input/output operations are no longer directed to the application but to whatever application is then in the foreground. In a minimized state, as exemplified in  FIG. 1   c , the window  10  and any other windows associated with the application are hidden, which facilitates access to windows associated with other applications previously operating in the background. The application remains launched but this is apparent only from an identification  12  of the application (the word “application” in  FIG. 1   c ) in a screen area referred to as the “tool bar” and indicated with reference numeral  13  in  FIGS. 1   a - 1   d . In an alternative minimized state shown in  FIG. 1   d , some applications are identified in what is referred to as the “XP system tray” indicated with the reference number  14 . A fictitious application icon  15  consisting of two intersecting ellipses has been shown in the XP system tray  14  to exemplify how an application associated with such an icon  15  would be identified in the XP tray  14 . 
         [0004]    Various user actions place a software application in its different operating states. When the user launches the application, as by clicking on an application icon, the operating system activates the application and places it in its foreground state. Launching another application, clicking in a window associated with another application, or clicking on the name of another application in the tool bar  13  incidentally places the application in its background state. When in the background state, clicking in the application window or clicking on the representation  12  of the application in the tool bar  13  brings the application to its foreground state. In the foreground state, clicking on a minimize button  16  associated with the application window  10  places the application in its minimized state. Thereafter clicking on the application&#39;s name  12  in the tool bar  13  returns the application to its foreground state. Clicking on an X-button  17  associated with the application window  10  will cause the application to return to its inoperative foreground state although some applications may remain referenced in the XP tray  14  (unless specific steps are taken to quit) in which case clicking on the icon representing an application in the XP system tray (such as the icon  15 ) brings the application to the foreground. 
         [0005]    There are shortcomings associated with such operation, which include time delays occasioned by manipulating a mouse and incidental diversion of a user&#39;s attention from work in progress. To avoid the delay and distraction occasioned by use of a mouse, many computer users prefer to use what are referred to as “keyboard equivalents” or “short cuts.” Keyboard equivalents often involve pressing an alphanumeric key contemporaneously with one or more modifiers keys, such as command, control, shift and alt/option keys, to invoke a desired menu command or to mimic the effect of clicking on a button. It is also known practice to associate application commands with a set of function keys so that clicking each function key triggers a different operation. A shortcoming associated with keyboard equivalents is the need to memorize what key has been assigned to what function. 
         [0006]    To facilitate use of keyboard equivalents, the Windows XP™ operating system has a “hotkeys” feature that permits a user to associate different software commands with key combinations specifically selected by the user and therefore easier to remember. The Skype application, for example, is compliant with this aspect of the Windows XP™ operating system, and a user is allowed to select keyboard equivalents to trigger several basic functions including answering a call, ignoring a call and rejecting a call. Although this approach is welcome, it is problematic, as a user remains obliged to learn and distinguish keyboard equivalents for several software applications. 
         [0007]    It is also known in the design of keyboards to provide a button and supporting software dedicated to the launching of a particular software application from an inoperative state. This avoids the need to search the desktop or directories to find and then click an application icon. Extending such practices to provide multiple buttons dedicated to invoking various functions for a particular software application is also know. However this approach requires individual buttons for the various functions, which increases the size and complexity of the keyboard. As keyboard manufacturers are already constrained to limit the size of keyboards, especially for laptop computers or hand-held electronic devices this approach is impractical. 
       SUMMARY 
       [0008]    In accordance with an aspect of the present disclosure there is provided a method of controlling a current operating state of an application. The method comprising the steps of receiving an input event associated with the application, determining the current operating state of the application associated with the received input event, determining a successor state of the application based on the determined operating state and changing the current operating state of the application to the determined successor state. 
         [0009]    In accordance with a further aspect of the present disclosure there is provided a computer program product for controlling a current operating state of an application. The computer program product comprising a computer readable medium embodying program code means for implementing a method comprising the steps of receiving an input event associated with the application, determining the current operating state of the application associated with the received input event, determining a successor state of the application based on the determined operating state, and changing the current operating state of the application to the determined successor state. 
         [0010]    In accordance with a further aspect of the present disclosure there is provided a keyboard for communicating with a computing device, the keyboard comprising a button adapted to send an input event to the computing device for changing a current operating state of an application to a successor state of the application, the current operating state of the application and the successor state of the application selected from a plurality of possible operating states. 
         [0011]    In accordance with a further aspect of the present disclosure there is provided a system for controlling a current operating state of an application, the system comprising a computing device and a keyboard. The computing device comprising a memory for storing instructions, a processor for executing the stored instructions, the executed instructions implementing an input component for receiving an input event associated with the application, a current operating state determination component for determining the current operating state of the application associated with the received input event, a successor state determination component for determining a successor state of the application based on the determined operating state and an operating state changing component for changing the current operating state of the application to the determined successor state. The keyboard device being coupled to the computing device. The keyboard device comprising a button adapted to send the input event associated with the application to the input component of the computing device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The system and method for controlling the operating states of an application will be described with reference to drawings in which: 
           [0013]      FIGS. 1   a - 1   d  are diagrammatic screen images stripped of detail and showing basic interface features characteristic of operating states; 
           [0014]      FIG. 2   a  depicts in a block diagram, exemplary components of a system for controlling a current operating state of an application; 
           [0015]      FIG. 2   b  depicts in a block diagram, exemplary logical components of a computing device for controlling a current operating state of an application; 
           [0016]      FIG. 3  depicts in a fragmented perspective view, part of a keyboard device in accordance with the system and method for controlling a current operating state of an application; 
           [0017]      FIG. 4  depicts in an exemplary block diagram the relationship among software and hardware component of the system for controlling a current operating state of an application; 
           [0018]      FIG. 5  depicts in a flow chart, a method of controlling a current operating state of an application; 
           [0019]      FIG. 6  depicts in an exemplary state transition diagram, operating states and transitions associated with the Windows™ applications; 
           [0020]      FIG. 7  depicts in an exemplary flow chart, the steps of controlling a current operating state of an application; 
           [0021]      FIG. 8  depicts in an exemplary state transition diagram, operating states and transitions associated with the Skype™ application; 
           [0022]      FIG. 9  depicts in an exemplary flow chart, the steps of a method of controlling a current operating state of an application; 
           [0023]      FIG. 10  depicts in a composite state diagram, both the operating system application states of the Skype™ application and the application-specific states characteristic of the Skype™ application; and 
           [0024]      FIG. 11  depicts in a state table, sets of condition that effectively define the operating states associated with the Skype™ application. In the state diagrams, phantom lines are used to identify state transitions incidental to operation of the operating system or operation of a software application itself. Solid lines are used to indicate transitions occasioned by pressing a button dedicated to a particular application for purposes of controlling its operating states. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0025]    The system and method for controlling a current operating state of an application will be described with reference to the Windows XP™ operating system of Microsoft Inc. and to a now popular software application identified with the trademark Skype™ that enables telephone communication using a voice-over-internet protocol (“VOIP”). It should be understood, however, that the present system and method of controlling the current operating state of an application has application to other operating systems, such as the Apple Macintosh™ operating system, that have a graphic user interface comprising windows and menus and that permit use of a mouse to select commands found in menus or to trigger execution of procedures or scripts associated with buttons, and to computing devices that have applications. 
         [0026]      FIG. 2   a  depicts in a block diagram exemplary components of a system  10  for controlling a current operating state of an application. The system comprises a computing device  20 . The computing device  20  is connected to a monitor  21  and a keyboard device  22  as further described herein. 
         [0027]      FIG. 2   b  depicts in a block diagram, exemplary logical components of a computing device  20  for controlling a current operating state of an application. The computing device  20  comprises an input component  205  for receiving an input event associated with the application, a current operating state determination component  210  for determining the current operating state of the application associated with the received input event, a successor state determination component  215  for determining a successor state of the application based on the determined operating state and an operating state changing component  220  for changing the current operating state of the application to the determined successor state. 
         [0028]      FIG. 3  depicts in a fragmented perspective view part of a keyboard device  22  in accordance with the system and method for controlling a current operating state of an application. The keyboard  22  comprises a set  27  of buttons along one side edge that are not standard. Each of the buttons  27  may typically be assigned to a different application for purposes of controlling its current operating state. For clarity of the description, one button  28  is assumed to have been dedicated to control of a Skype™ application  25 , and another button  29 , to the other Windows™ application  26 . 
         [0029]      FIG. 4  depicts in an exemplary block diagram the relationship among software and hardware component of the system  10  for controlling a current operating state of an application. The computing device  20  comprises a memory (not shown) for storing instructions and data, as well as a processor (not shown) for executing stored instructions. When executed by the processor the stored instructions may provide software for operating the computing device  20 . The software may include the Window XP™ operating system  23 , a custom keyboard program  24  that may load into RAM automatically on boot-up of the computing device  20 , the Skype™ application  25 , and another software application  26 , which may be any Windows XP™ compliant software application and which is consequently referred to simply as the “other Windows™ application.” 
         [0030]    Referring to  FIG. 4 , when either of the buttons  28 ,  29  are pressed, the keyboard  22  transmits a signal corresponding to the pressed button  28  or  29  to the computer&#39;s printed circuit board  30  via USB circuitry  31  associated with the keyboard  22  and a USB port  32  associated with the computer&#39;s circuit board  30 . Initially a Human Input Device (HID) keyboard driver  33  associated with the operating system  23  handles the signal and generates an input event based on the signal. Since the signal is not a conventional keyboard signal, the custom keyboard program  24  ultimately receives the input event. 
         [0031]      FIG. 5  depicts in a flow chart, a method of controlling a current operating state of an application. The method begins when the input event is received by the custom keyboard program  24 . After receiving the input event, the keyboard program  24  determines the current operating state of the application, as at step  34 . The keyboard program  24  may then accesses stored data identifying successor states for the operating states associated with the application, and determines an appropriate successor state corresponding to the current operating state, as at step  35 . The keyboard program  24  then places the application in the successor state, changing the current operating state of the application to the determined successor state, as indicated at step  36 . The successor state may optionally be set not only in response to the current operating state but one or more prevailing conditions as apparent from state diagrams and flow charts dealing with more specific implementations of described further herein. 
         [0032]      FIG. 6  depicts in an exemplary state transition diagram, operating states and transitions associated with the other Windows™ application  26 . The states of  FIG. 6  are common to many Windows™ applications, as such they may be referred to as operating system application states. The system and method for controlling a current operating state of an application may be used advantageously to control the states of a Windows™ application. If the button  29  associated with the other Windows™ application has been pressed, only the operating system application states shown in  FIG. 6  are involved in determining the successor state. The operating system application states include the inoperative state S 1 , the foreground state S 2 , the background state S 3 , and minimized states S 4 , S 5 . In the example depicted in  FIG. 6 , the foreground state S 2  is identified as the successor state for each of the inoperative, background and both minimized states S 1 , S 3 , S 4 , S 5 . The successor state for the foreground state S 2  is the minimized state S 4  in the toolbar, and this allows a user to conveniently toggle between the foreground state S 2 , where input/output operations are directed to the other Windows™ application  26 , and the minimized state S 2 , where the application  26  is essentially hidden, using a single button. This functionality allows access to windows (not shown) associated with other applications previously operating in the background. Each of the transitions T 1 -T 5  between states S 1 -S 5  involves a single tap of the assigned button  29 . Several state transitions may be occasioned by operation of the other Windows™ application  26  or the operating system  23 . For example, the transition T 6  from the foreground state S 2  to the background state S 3  may be occasioned by launching a new application or by bringing another application into the foreground. Transition T 7  from the foreground state S 2  to the minimized state S 5  in the XP tray may be occasioned when the user clicks on an X-button (not shown) associated with the window of the other Windows™ application  26 . The transitions T 8 , T 9  to the inoperative state may occur when the user exits the other Windows™ application  26 . The operating state S 5  in the XP tray will normally be restricted to particular applications designated to use the XP tray. 
         [0033]      FIG. 7  depicts in an exemplary flow chart, the steps of controlling a current operating state of an application. In response to receiving an input event indicating the pressing of the button  29 , the keyboard program  24  implements the steps of the flow chart shown in  FIG. 7 . After receiving the input event, the keyboard program  24  queries the operating system to determine the current operating state of the application associated with the input event, which will be an operating system application state, of the other Windows™ application  26 , as at step  37 . The keyboard program  24  then branches according to the determined current operating state, and an appropriate successor state is determined. The appropriate successor state may be determined using data stored in the software algorithm itself, as at steps  38 ,  39 ,  40 ,  41 ,  42 . Alternatively, the data may be stored in a file or data structure in the memory of the computing device  20  (see  FIG. 2   a ). Once the successor state has been determined, the other Windows™ application  26  is placed in the determined successor state, changing the current operating state of the application to the determined successor state, as at step  43 . The changing of the current operating state of the application to the determined successor state may be accomplished by posting an event with the operating system  23  that requires the application either to come to the foreground or to minimize itself. This functionality is consequently available for use with all Windows XP™ compliant applications. 
         [0034]      FIG. 8  depicts in an exemplary state transition diagram operating states and transitions associated with the Skype™ application  25 . In addition to the operating system application states, an application may have its own different operating states, referred to as application-specific states. For example, the application-specific states of the Skype™ may include an idle state S 6  in which the Skype™ application  25  is executing but not engaged in handling of a telephone call, a calling state S 7  in which the software dials a specified telephone number and attempts to complete a telephone connection, a first call-handling state S 8  in which the software enables a telephone conversation with a first person (identified only as “P 1 ” in the flowcharts) who is either an outside caller or the recipient of an outgoing call, and a second call-handling state S 9  in which the software places the first person P 1  on hold and enables a telephone conversation with a second person (identified only as “P 2 ” in the drawings) who may be an outside caller. An input event indicating a single tap of the button  28  assigned to the Skype™ application may cause the state transitions T 11 -T 14  and T 16 , T 17 . 
         [0035]    The overall operation occasioned with each such state transition is identified in  FIG. 8  adjacent to the curved line representing the transition. It is understood that a state transition may be occasioned by changing the current operating state of an application to a successor state. For example, state transition T 11  involves answering a call from an outside caller, as indicated by the expression “answer call” adjacent to the state transition T 1 . State transition T 14  is occasioned by inherent operation of the Skype™ application  25 , which automatically moves the Skype™ application from its calling state S 7  to its first call-handling state S 8  in response to the person P 1  answering the outgoing call. Transitions T 10  and T 15  are circular indicating that the Skype™ application  25  remains in its then current operating state. Such transitions may be triggered by receiving an input event indicating that the assigned button  28  has been pressed and held, for example, for about 1.5 seconds. Such operation of the assigned button  28  very conveniently adds functionality, which may indicate the user&#39;s intention to reject an incoming call in the idle state S 6  or to reject an incoming call from a second person P 2  in the first call-handling state S 8 . The Skype™ application  25  is made to respond accordingly. This is achieved by communicating with the Skype™ application  25  through an application program interface (API)  44  (see  FIG. 4 ), which is associated with the Skype™ application  25 . 
         [0036]    The AP  44 I may be used to determine the application-specific state of the Skype™ application, which may be used in determining the current operating state in stead of, or in addition to, the operating system application states. The API  44  can be queried to identify various conditions, for example, whether the Skype™ application is currently idle, whether the user has specified a telephone number that is to be dialed, whether there is currently an incoming call, whether the Skype™ application  25  is currently handling a call, and whether a second, incoming call is detected during handling of a current call. Similarly, state transitions in the Skype™ application  25  are triggered through the API  44 , changing the current operating state of the Skype™ application. 
         [0037]    At least one advantage achieved is that the Skype™ application  25  can be stepped through its various operating states, accepting, rejecting, and handling calls, by simply pressing the assigned button  28 . The user is not obliged to learn various key equivalents but progresses naturally between states by operating a single button  28 . Furthermore, only a single button on the keyboard is required to achieve the changing of the operating states of the application, which may reduce the size of the keyboard. 
         [0038]      FIG. 9  depicts in an exemplary flow chart, the steps of a method of controlling a current operating state of an application. In response to receiving an input event indicating the pressing of the button  28 , the keyboard program  24  implements the steps of the flow chart shown in  FIG. 9 . After receiving the input event, the keyboard program  24  queries the API  44  to determine the current operating state, which may be an application-specific state, of the Skype™ application  26 , as at step  45 . Once the current operating state has been determined the keyboard program  24  branches accordingly. If the Skype™ application  25  is in its idle state S 6 , the program queries the API  44  to determine whether there is an incoming call (step  46 ). If so, it determines whether the received input event indicates that the user has pressed and is holding the button  28  down (step  47 ). If that condition is met, the program instructs the Skype™ application  25  via the API  44  to reject the call (step  48 ). Otherwise, the program places the Skype™ application  25  in its first call-handling state (step  49 ). If there is currently no incoming call, the program queries the API  44  to determine whether an outgoing call has been specified (step  50 ), and accordingly places the Skype™ program, through the API  44 , in its calling state S 7  (step  51 ). 
         [0039]    If the Skype™ application  25  is in its calling state S 7  when the input event is received indicating that the button  28  is pressed, the keyboard program  24  instructs the Skype™ application  25  via the API  44  to change its current operating state to its idle state, incidentally canceling the outgoing call, as at step  52 . 
         [0040]    If the Skype™ application  25  is in its first call-handling state when the input event is received indicating that the button  28  is pressed, the keyboard program  24  uses the API  44  to determine if there is an incoming call from a second person P 2  (step  53 ). If so, the keyboard program  24  checks whether the input event is received indicating that the user is holding the button  28  down (step  54 ), and if so, instructs the Skype™ application  25  via its interface to reject the call (step  55 ). Otherwise, the program places the Skype™ application  25  via its API  44  into its second call-handling state (step  56 ), incidentally placing the first person P 1  on hold and enabling a conversation with the second person P 2 . Otherwise, with no incoming call, the keyboard program  24  assumes the user wishes to end the current conversation with the person P 1 , and changes the current operating state of the Skype™ application  25  to the determined successor state which is the idle state S 6  as at step  57 . 
         [0041]    If the Skype™ application  25  is in its second call-handling state with a first person P 1  on hold when the input event is received indicating the button  28  is pressed, the keyboard program  24  assumes that the user wishes to end his conversation with person P 2 . It then instructs the Skype™ application  25  via the API  44  to return to its first calling state (step  58 ), incidentally terminating the call with the person P 2  and once again enabling conversation with the person P 1 . 
         [0042]    As described above the current operating state and the successor state of an application (whether the other Windows™ application or the Skype™ application) may be selected from a possible set of operating states. The possible operating states may include operating system application states and/or application-specific states. 
         [0043]      FIG. 10  depicts in a composite state diagram, both the operating system application states of the Skype™ application  25  (common to all Windows XP™ applications) and the application-specific states characteristic of the Skype™ application  25  itself. Several aspects of the diagram should be noted. First, reference labels used in the state diagrams of  FIGS. 6 and 8  have been preserved in  FIG. 10 , and the description above of corresponding states and transitions is applicable and will not be repeated. The idle state S 6  of the Skype™ application  25  as identified in  FIG. 10  corresponds to the foreground state S 2  illustrated in  FIG. 6 . Transitions T 1 -T 7  of  FIG. 6  are now shown to and from the idle state S 6 . The Skype™ application  25  has not only the two minimized states S 4 , S 5  shown in  FIG. 4  but also a third minimized state S 10 . In addition to the background state S 3  of  FIG. 6 , there are now two additional background states, a second background state S 11  and a third background state S 12 . 
         [0044]    A transition T 19  from the first call-handling state S 8  to the second background state S 11  occurs when the Skype™ application  25  is placed in the background by user actions that bring another application to the foreground. A transition T 20  from the second background state S 11  back to the first call-handling state S 8  is caused by tapping the assigned button  28  but also occurs automatically when the Skype™ application  25  responds to an incoming call from a second person P 2  while a first person P 1  is on hold. A transition T 21  from the second call-handling state S 9  to the third background state S 12  occurs when user action brings another application to the foreground, and a transition T 22  from the third background state S 13  back to the second call-handling state S 9  is caused by tapping the assigned button  28 . In the third background state S 12 , a user can terminate a conversation with a second person P 2  by pressing and holding the assigned button  28 , which causes a transition T 23  to the first calling-handling state S 8  where the user can once again converse with a first person P 1  who has been on hold. 
         [0045]    The Skype™ application  25  makes a transition T 24  from its first call-handling state S 8  to its third minimized state S 10  in response to clicking on a minimize button in the application window. Once in the third minimized state S 10 , the Skype™ application  25  makes a transition T 25  back to its first call-handling state S 8  in response to the user tapping the assigned button  28  or automatically in response to detection of an incoming call from a second person P 2 . In the third minimized state, the user can press and hold the assigned button  28  to end a telephone conversation with a first person P 1  in which case the Skype™ application  25  makes a transition T 26  back to the idle state S 6 . 
         [0046]      FIG. 11  depicts in a state table, sets of condition that effectively define the eleven operating states S 1 , S 3 -S 12  associated with the Skype™ application  25 . Under the heading “CONDITIONS” are three columns in which codes are assigned to various conditions. These codes are used under the heading “COMPOSITE STATE CODE” to identify the characteristics of each state. For instance, the column with the heading “S 6 ” contains four codes defining the characteristics of the idle state S 6 : (1) “R” which identifies that the Skype™ application  25  is running and not inoperative; (2) “E” which identifies that the application window associated with the Skype™ application  25  is expanded (the application has not been minimized); (3) “F” which identifies that the Skype™ application  25  is in the foreground; and (4) “N” which identifies that the Skype™ application  25  is not handling a telephone call. The code “NA” identifies that a particular characteristic is not applicable to a particular operating state. 
         [0047]    The system and method for controlling a current operating state of an application has particular application to applications running on operating systems that provide operating system application states to applications, such as for example a calculator, web browser, email program etc. The operating system application states may include, for example, non-operative, foreground, background and minimized states of operation corresponding to those described above with reference to the Window XP™ operating system. To that end, data may be stored, for example to identify the foreground state of an application as the successor state to each of the non-operative state, background and minimized states. One minimized state may be identified as the successor state of the foreground state, which then allows toggling of the application between foreground and minimized states with repeated pressing of the assigned button. 
         [0048]    The system and method for controlling a current operating state of an application also has particular application to applications that have different operating states, for example, communication software applications adapted to implement VOIP telephone communication, such as the Skype™ software application discussed above. Such software may have operating system application states as mentioned above but will also have application-specific states associated with, for example, telecommunication functions. The application-specific states may include an idle state in which the software application is executing but not engaged in handling of a telephone call; a calling state in which the software application dials a specified telephone number and attempts to complete a telephone connection; a first call-handling state in which the software application enables a telephone conversation with a first person, and a second call-handling state in which the software places the first person on hold and enables a telephone conversation with a second person who happens to call. In such a context, the data to be stored may identify the calling state as a successor to the idle state if the assigned button is pressed while a telephone number for an outgoing telephone call is specified. The first call-handling state may be identified as a successor to the idle state if the button is pressed during an incoming call, and the idle state may be identified as a successor to both call-handling states. More specifically, the idle state is identified as the successor to the first call-handling state if the assigned button is pressed while there is no incoming call; the second call-handling state is identified as a successor to the first call-handling state if the assigned button is pressed in response to a second person making an incoming call; and the first call-handling state may be identified as a successor to the second call-handling state. The advantage obtained is that the user can step the application through various operating states, handling incoming and outgoing telephone calls, with just a single button. 
         [0049]    Although the system and methods have been described in detail with reference to a computing device and keyboard, it is understood that the system and methods may be advantageously used in other devices, such as for example, a cell phone, a personal digital assistant (PDA), a smart phone, etc. For example, a cell phone may utilize the system and methods described herein to replace multiple buttons used for initiating a call and ending a call with a single button that determines the operating state of the cell phone determines a possible successor state to place the phone in depending on at least the determined operating state, and then places the cell phone in the determined possible successor state. 
         [0050]    The system and methods according to the present patent disclosure may be implemented by any hardware, software or a combination of hardware and software having the above described functions. The software code, either in its entirety or a part thereof, may be stored in a computer-readable memory. Further, a computer data signal representing the software code which may be embedded in a carrier wave may be transmitted via a communication network. Such a computer-readable memory and a computer data signal are also within the scope of the present patent disclosure, as well as the hardware, software and the combination thereof. 
         [0051]    While particular embodiments of the present patent disclosure have been shown and described, changes and modifications may be made to such embodiments without departing from the true scope of the patent disclosure.