IRecoordHandler

The IRecoordHandler class handles the notification that a window or control is being resized.

A recoordination event notifies a window when the size and position of the window's client area must be calculated. This event is processed by this handler to make any adjustments in child window coordinates which are necessary due to the window size change. This handler is distinct from an IResizeHander in that it runs before the IResizeHander and processes a different message. The message handled by the IRecoordHandler is WM_CALCVALIDRECTS/WM_NCCALCSIZE.

IRecoordHandler processes the resizing event by creating an IRecoordEvent object and routing it to the virtual windowSizeChanged function. You can override this virtual function to supply your own specialized processing of a resizing event.

The following return values from the virtual functions specify whether the window event is passed on for additional processing:

true
The resizing event requires no additional processing. Do not pass it to another handler.
false
The resizing event requires additional processing. Pass the resizing event to the next handler for additional processing, as follows:
  • If there is another handler for the window, pass the resizing event to the next handler.
  • If this is the last handler for the window, call IWindow::dispatch to dispatch the event to the window's owner window.
  • If this is the last handler for the owner window, call IWindow::defaultProcedure to process the event.


IRecoordHandler - Member Functions and Data by Group

Constructors & Destructor

The only way to create objects of this class is by using the default constructor.


[view class]
~IRecoordHandler
public:
virtual ~IRecoordHandler()

Supported Platforms

Windows OS/2 AIX
Yes Yes Yes


[view class]
IRecoordHandler
public:
IRecoordHandler()

Used by derived classes to construct objects of this class. This is the default constructor and accepts no parameters.

Supported Platforms

Windows OS/2 AIX
Yes Yes Yes


Event Dispatching

Event-dispatching members evaluate an event to determine if it is appropriate for this handler object to process it. If it is, it calls the virtual function used to process the event.


[view class]
dispatchHandlerEvent
protected:
virtual bool dispatchHandlerEvent(IEvent& event)

If a resizing event is received, the windowSizeChanged virtual function is called.

Supported Platforms

Windows OS/2 AIX
Yes Yes Yes


Event Processing

Event-processing members must be supplied to process events affecting recoordination. You can override these virtual members in a derived class.


[view class]
windowSizeChanged
protected:
virtual bool windowSizeChanged( IWindowHandle handle, const IRectangle& newWindowRect, const IRectangle& oldWindowRect )

Processes resizing events. This member is called when the event indicates that the size of the window with window handle handle has changed. It is implemented by derived classes.

Supported Platforms

Windows OS/2 AIX
Yes Yes Yes


IRecoordHandler - Inherited Member Functions and Data

Inherited Public Functions

IHandler
IRecoordHandler

Inherited Public Data

Inherited Protected Functions

IHandler

Inherited Protected Data