How to disable the ability of a MDI child form to move

Problem/Question/Abstract:

I try to disable the ability to move MDI children around. Problem is that if I have tiled for example 2 MDI's, I cannot change focus to another one.

Answer:

procedure TForm1.WMSyscommand(var msg: TWMSyscommand);
begin
  if (msg.cmdtype and $FFF0) <> SC_MOVE then
    inherited;
end;