private
procedure WMGetMinMaxInfo(var Msg: TWMGetMinMaxInfo); message WM_GETMINMAXINFO;
end;
{...}
implementation
procedure TForm1.WMGetMinMaxInfo(var Msg: TWMGetMinMaxInfo);
begin
inherited;
with Msg.MinMaxInfo^ do
begin
ptMinTrackSize.x := Form1.Width;
ptMaxTrackSize.x := Form1.Width;
ptMinTrackSize.y := Form1.Height;
ptMaxTrackSize.y := Form1.Height;
end;
end;