TBitmap.Handle Property

Provides access to the Windows GDI bitmap handle for accessing the GDI bitmap object.

Pascal

property Handle: HBITMAP;

C++

__property HBITMAP Handle;

Description

Use Handle to call a Windows API function that requires the handle of a bitmap object. Pass Handle as the bitmap handle parameter to these functions.

Handle is the HBITMAP encapsulated by the bitmap object. Avoid grabbing the handle directly since it causes the HBITMAP to be copied if more than one TBitmap shares the handle.

Warning: Be careful when giving the handle to an object or routine. If the receiver takes ownership (and destroys) the bitmap handle, call TBitmap.::ReleaseHandle.

Delphi Examples:

Copy Code

{
This example shows how to add custom cursors to an
application.  The following code makes this cursor available
to the application via the constant crMyCursor, and sets it
as the global cursor to the application.
} 
var
  bmpMask : TBitmap;
  bmpColor : TBitmap;
  iconInfo : TIconInfo;
const
  crMyCursor = 5;

procedure TForm1.Button2Click(Sender: TObject);
begin
  bmpMask := TBitmap.Create;
  bmpColor := TBitmap.Create;

  bmpMask.LoadFromFile('SquareMask.bmp');
  bmpColor.LoadFromFile('Square.bmp');

  with iconInfo do
  begin
    fIcon := false;
    xHotspot := 15;
    yHotspot := 15;
    hbmMask := bmpMask.Handle;
    hbmColor := bmpColor.Handle;
  end;

  Screen.Cursors[crMyCursor] := CreateIconIndirect(iconInfo);
  
  Screen.Cursor := crMyCursor;

  bmpMask.Free;
  bmpColor.Free;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  DestroyIcon(Screen.Cursors[crMyCursor]);
end;