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Drawing on the MDI Parent Form (Correct)

Title: Drawing on the MDI Parent Form (Correct) Question: How to correct paint something on MDI Parent Form Code based on article #1144 Answer: type tform1 = class(tform) image1 : timage ; // load the background image here, // and set the visible property to false procedure formcreate(sender : tobject); // for initialize canvas procedure formdestroy(sender : tobject); // must be destroy canvas // two events for refresh procedure formpaint(sender : tobject); // the correct event for paint procedure formresize(Sender : tobject); // the correct event for paint private background_canvas : tcanvas ; // pointer to MDI canvas end ; procedure tform1.formcreate(sender : tobject) ; begin background_canvas := tcanvas.create; background_canvas.handle:=getdc(clienthandle); end ; procedure tform1.formdestroy(sender : tobject); begin releasedc(clienthandle,background_canvas.handle); background_canvas.free; end ; procedure Tf_main.FormPaint(Sender: TObject); begin // on this event you can draw background_canvas.draw(0,0,image1.Picture.Graphic) ; end; procedure tform1.formresize(sender: tobject); begin // on this event you can draw background_canvas.draw(0,0,image1.Picture.Graphic) ; end;