VkInterruptDialog(3x)					 VkInterruptDialog(3x)

NAME    [Toc]    [Back]

     VkInterruptDialog - A dialog manager that support interrupts

INHERITS FROM    [Toc]    [Back]

     VkBusyDialog : VkDialogManager : VkComponent : VkCallbackObject

HEADER FILE    [Toc]    [Back]

     #include <Vk/VkInterruptDialog.h>

PUBLIC PROTOCOL	SUMMARY
   Constructor/Destructor
	   VkInterruptDialog(const char* name);
	   virtual void	~VkInterruptDialog(void);


   Checking for	Interrupts
	   Boolean wasInterupted(void);

CLASS DESCRIPTION    [Toc]    [Back]

	  This class supports applications that	need to	perform	a lengthy task
	  and allow the	task to	be interrupted.	To use the dialog,
	  applications must use	the VkApp::setBusyDialog() method to install
	  an instance of VkInterruptDialog as the application's	current	busy
	  dialog, and then call	VkApp::busy() Applications must	periodically
	  check	to see if the application has been interrupted.	The period of
	  time between checks is up to the application,	which must weigh
	  responsiveness against time spent checking.

	  Note that checking for interrupts involves entering a	secondary
	  event	loop for a short time, so the application must beware of reentrancy
 problems in any callbacks that could	be invoked.

FUNCTION DESCRIPTIONS    [Toc]    [Back]

   VkInterruptDialog()
	   VkInterruptDialog(const char* name);


	  Initialize a VkInterruptDialog object. Normally, applications	can
	  use the globally instantiated	theInterruptDialog.

   ~VkInterruptDialog()
	   virtual void	~VkInterruptDialog(void);


	  Free the memory associated with a VkInterruptDialog object.

   wasInterupted()





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VkInterruptDialog(3x)					 VkInterruptDialog(3x)



	   Boolean wasInterupted(void);


	  Check	to see if the user has pushed the dialog's "cancel" button
	  since	the last time this function was	called.

DATA MEMBER DESCRIPTIONS    [Toc]    [Back]

   const char* const interruptedCallback;
	   static const	char *const interruptedCallback;


	  This callback	list allows objects to register	a member function to
	  be called when the user selects the "Cancel" button of a
	  VkInterruptDialog dialog. This callback can only be called if	the
	  application calls wasInterrupted(). Normally,	the application	will
	  test the return value	of this	function, but the callback may be
	  useful in other situations.

EXAMPLE    [Toc]    [Back]

	  The following	code segment installs the interrupt dialog, and
	  performs a simulated lengthy task, checking for interrupts
	  periodically.


	   int i, j, k = 0;

	    // Install the interruptible dialog	as the
	    // dialog to post when busy

	    theApplication->setBusyDialog(theInterruptDialog);

	    // Start being "busy"

	    theApplication->busy("Very Busy",
				 (BusyWindow *)	clientData);

	    k =	0;

	    for(i=0; i<10000; i++)
	    {
		 // Every so often, see	if the task
		 // was	interrupted

		  if(theInterruptDialog->wasInterupted())
		  {
		      break;  // kick out of current
			      // task if user interrupts
		  }

		  sleep(1);
	      }




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VkInterruptDialog(3x)					 VkInterruptDialog(3x)



	      // Task done, so we're not busy anymore

	      theApplication->notBusy();

	      // Restore the application's busy	dialog
	      // as the	default

	      theApplication->setBusyDialog(NULL);

INHERITED MEMBER FUNCTIONS    [Toc]    [Back]

   Inherited from VkDialogManager
	  show(), hide(), className(), clearCache(), prepost(),	ok(),
	  cancel(), apply(), setTitle(), setButtonLabels(), unpost(),
	  unpostAll(), centerOnScreen(), lastPosted(), post(), postModal(),
	  postBlocked(), postAndWait(),	post(),	_action, _showOK, _showCancel,
	  _showApply, _allowMultipleDialogs, _minimizeMultipleDialogs,
	  prepostCallback


   Inherited from VkComponent    [Toc]    [Back]
	  installDestroyHandler(), removeDestroyHandler(), widgetDestroyed(),
	  setDefaultResources(), getResources(), manage(), unmanage(),
	  baseWidget(),	okToQuit(), _name, _baseWidget,	_w, deleteCallback


   Inherited from VkCallbackObject    [Toc]    [Back]
	  callCallbacks(), addCallback(), removeCallback(),
	  removeAllCallbacks()


VIEWKIT	2.1 CHANGES
     In	multi-screen enabled applications or components, references to
     theInterruptDialog	will only be valid for the default screen in the
     application.  The following new function API will return the
     VkInterruptDialog associated with the appropriate screen and should be
     used instead of theInterruptDialog;


	   VkInterruptDialog *getAppInterruptDialog(VkComponent	*comp);


CLASSES	USED BY	THIS CLASS
     VkApp

SEE ALSO    [Toc]    [Back]

     VkBusyDialog, VkDialogManager, VkComponent, VkApp
     ViewKit Programmer's Guide
     The X Window System, DEC Press, Bob Sheifler and Jim Gettys
     The X Window System Toolkit, DEC Press, Paul Asente and Ralph Swick
     The OSF/Motif Programmers Reference, Prentice Hall, OSF



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VkInterruptDialog(3x)					 VkInterruptDialog(3x)


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