ControlDragging was: Re: [lazarus] CVS Changes

Marc Weustink weus at
Thu Jun 15 16:08:58 EDT 2000

At 21:24 15-06-2000 +0200, Alexander Reiter wrote:
>i think the problem is in TDesignerForm.MouseMove.
>if you try this, you can move your control. well is not the
>best solution, but it is a good starting point. take a look
>at this:
>  Procedure TDesignerForm.MouseMove(Sender: TObject; Shift: TShiftState;
>X, Y: Integer);
>   dx, dy: Integer;
>   //if TCOntrol(sender).dragging then
>   if (FMoveCOntrol.Control = Sender)
>   then begin
>     WriteLn(Format('[TDesignerForm.MouseMove] Start(%d, %d) Stop(%d,
>%d)', [FMoveCOntrol.X, FMoveCOntrol.Y, X, Y]));
>   not correct  --> //dx := X - FMoveCOntrol.X;
>   not correct  --> //dy := Y - FMoveCOntrol.Y;
>      dx := X - FMoveControl.Control.Left;
>      dy := Y - FMoveControl.Control.Top;
>     FMoveControl.Control.Left := FMoveControl.Control.Left + dX;
>     FMoveControl.Control.Top  := FMoveControl.Control.Top + dY;
>   end;

Don't think so.
X and Y are the coordinates of the mousepointer within the control at the 
moment of the mousedown/move event, so you must calc the relave 
displacement from these points and not from the left and top. Otherwise you 
are comapring two different things.


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