How to make the form could be dragged over any arbitrary area of ​​the form?

  • In the simplest case, process WM_NCHITTEST and return HT_CAPTION - karmadro4

2 answers 2

One of the options, the most cute to me.

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer); begin ReleaseCapture; SendMessage(Form1.Handle, WM_SYSCOMMAND, $F012, 0) ; end;
  • The magic number is not cute at all :( - karmadro4
  • Alas, SC_DRAGMOVE in Dephi is not defined anywhere. - Nofate ♦
  • The nice thing here is that everything about everything took 2 lines and one handler. - Nofate ♦
  • > Alas, SC_DRAGMOVE in Dephi is not defined anywhere. Pretty weak excuse. By the way, the method with WM_NCHITTEST will be no less concise. - karmadro4
  • Nobody forbids you to write somewhere const SC_DRAGMOVE = $F012; > By the way, the method with WM_NCHITTEST will be no less concise. I agree. But the WM_NCHITTEST method has one drawback: mouse events will no longer come to the form. - Nofate ♦ 2:29 pm

Add the following to the form announcement:

 type TForm1 = class(TForm) ... private { Private declarations } procedure WMNCHITTEST(var Msg: TWMNCHitTest);message WM_NCHITTEST;

and write the following in the code itself:

 procedure TForm1.WMNCHITTEST(var Msg: TWMNCHitTest); begin Inherited; with Msg do if Result = htClient then Result := htCaption; end;