Taxonomy Categories:
Member Functions:
Interface Category:
API.
Inherits From:
TCanvasInteractor
Inherited By:
TCanvasGraphicRotatingInteractor
TCanvasGraphicScalingInteractor
TCanvasGraphicTranslatingInteractor
TCanvasLineDragInteractor
TCanvasPolylineDragInteractor
TCanvasRectDragInteractor
TCanvasTextGraphicCreationInteractor
Purpose:
Models a drag style interaction. Drag interaction begins with a mouse down, continues with subsequent mouse moves, and ends with a mouse up. Derived classes implement how each stage of interaction is used to accomplish a specific task, such as do a command. Derived classes also implement drawing of feedback if required.
Instantiation:
Allocate on the heap or the stack.
Deriving Classes:
Abstract base class; must be derived.
Intended to be derived for drag style interaction, such as line or curve creation.
Concurrency:
Not multithread safe.
Resource Use:
No special requirements.
TCanvasDragInteractor (MToolHandler *)
Interface Category:
API.
Purpose:
Constructor.
Calling Context:
Called by constructors of derived classes.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual ~ TCanvasDragInteractor ()
Interface Category:
API.
Purpose:
Destructor.
Calling Context:
Called to destroy an object.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual bool MouseDown (TMouseDownEvent &)
Interface Category:
API.
Purpose:
Handles the mouse-down event in the context of drag interaction.
Calling Context:
Called by the Mouse Input framework. Clients do not call this function. Derived classes must call the base class implementation.
Parameters:
Return Value:
Returns true because the mouse-down event is always handled.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual bool MouseMoved (TMouseMovedEvent &)
Interface Category:
API.
Purpose:
Handles the mouse-moved event in the context of drag interaction.
Calling Context:
Called by the Mouse Input framework. Clients do not call this function. Derived classes must call the base class implementation.
Parameters:
Return Value:
Returns true because the mouse-moved event is always handled.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual bool MouseUp (TMouseUpEvent &)
Interface Category:
API.
Purpose:
Handles the mouse-up event in the context of drag interaction.
Calling Context:
Called by the Mouse Input framework. Clients do not call this function. Derived classes must call the base class implementation.
Parameters:
Return Value:
Returns true because the mouse-up event is always handled.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual void DrawFeedback ()
Interface Category:
API.
Purpose:
Implements how feedback is drawn.
Calling Context:
Called by mouse event handling functions of this class.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual void StartInteraction ()
Interface Category:
API.
Purpose:
Implements what semantic action takes place when interaction starts. Typically, a command binding is executed by calling MToolInteractor::DoBegin.
Calling Context:
Called from the MouseDown of this class.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual void ContinueInteraction ()
Interface Category:
API.
Purpose:
Implements what semantic action takes place as interaction continues. Typically, a command binding is executed by calling MToolInteractor::DoIncrement.
Calling Context:
Called from the MouseMoved of this class.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual void EndInteraction ()
Interface Category:
API.
Purpose:
Implements what semantic action takes place when interaction ends. Typically, a command binding is executed by calling either MToolInteractor::AdoptAndDoEnd or MToolHandler::AdoptAndDo.
Calling Context:
Called from the MouseUp of this class.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
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