The IResizeHandler class handles the notification of resizing events. These events notify a window or control that it has increased or decreased on the screen.
Create a handler derived from IResizeHandler and attach it to a window or control. You can do this by calling IHandler::handleEventsFor to pass the window or control to the resize handler.
When the resize handler receives a resize event, it creates a IResizeEvent object and routes that object to the virtual function IResizeHandler::windowResize. You can override this virtual function to supply your own specialized processing of a resize event.
The return value from the virtual function specifies whether the resize event should be passed on for additional processing, as follows:
Constructors & DestructorOnly derived classes can construct objects of this class.
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protected:
IResizeHandler()
Derived classes call this default constructor to create objects of this class.
| Windows | OS/2 | AIX |
| Yes | Yes | Yes |
Event DispatchingThe Open Class Library dispatches events that have been sent or posted to a window to the handlers attached to that window. It does this by calling the event-dispatching function of the handler objects. An IResizeHandler object processes only window-resizing events.
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protected:
virtual bool dispatchHandlerEvent(IEvent& event)
If a resize event is received, this function calls the appropriate virtual function.
| Windows | OS/2 | AIX |
| Yes | Yes | Yes |
Event ProcessingA resize handler contains an event-processing member that you use to process a window-resizing event. You should override this virtual function in a derived class.
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protected:
virtual bool windowResize(IResizeEvent& event) = 0
Implemented by derived classes to handle a resizing event. A derived class must supply this function.
| Windows | OS/2 | AIX |
| Yes | Yes | Yes |
virtual ~IHandler()
virtual IString asDebugInfo() const
virtual IString asString() const
virtual IHandler& disable()
virtual IHandler& enable(bool enable = true)
virtual IHandler& handleEventsFor(IWindow* window)
IHandler()
bool isEnabled() const
virtual IHandler& stopHandlingEventsFor(IWindow* window)
virtual IEventResult defaultProcedure(IEvent& event)
virtual bool dispatchHandlerEvent(IEvent& event) = 0