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Example: Overriding a Message Handler

For example, to override a component's handling of the WM_PAINT message, you redeclare the WMPaint method:

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type
  TMyComponent = class(...)
  .
  .
  .
  procedure WMPaint(var Message: TWMPaint); message WM_PAINT;
end;

 

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class PACKAGE TMyComponent : public TComponent
{
protected:
    void __fastcall WMPaint(TWMPaint* Message);
BEGIN_MESSAGE_MAP
  MESSAGE_HANDLER(WM_PAINT, TWMPaint, WMPaint)
END_MESSAGE_MAP(TComponent)
};
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