[델파이]MDIChild Client Rect 변경

in the OnCreate event place the following code:

[Delphi]
  if ClientHandle <> 0 then
    Winapi.Windows.SetParent(ClientHandle, pnlMDI.Handle);

where pnlMDI is a TPanel that can be placed anywhere on the form. This however is not enough. The MDIClient is moved and sized in TCustomForm.AlignControls which needs to be overridden to keep it occupying the whole panel it has been parented to. In the form's interface add the following code just before the "public" declaration:

[Delphi]
  protected
    procedure AlignControls(AControl: TControl; var Rect: TRect); override;

and in the implementation of AlignControls add the following code:

[Delphi]
procedure TYourForm.AlignControls(AControl: TControl; var Rect: TRect);
var
  R: TRect;
begin
  inherited AlignControls(AControl, Rect);
  if ClientHandle <> 0 then
  begin
    SetRect(Rect, 0, 0, pnlMDI.Width, pnlMDI.Height);
    with Rect do
      SetWindowPos(ClientHandle, HWND_BOTTOM, Left, Top, Right - Left,
        Bottom - Top, SWP_NOZORDER + SWP_NOACTIVATE);
    if FormStyle = fsMDIForm then
      if Winapi.Windows.GetClientRect(ClientHandle, R) then
        InvalidateRect(ClientHandle, nil, True);
  end;
end;

Note: this code isn't ideal. The inherited call moves the MDI Client and we are moving back immediately after, however we cannot get rid of this overhead without a major overhaul of the TClientForm code.