自己不会看source呀，delphi好几年没用了
procedure TApplication.Minimize;
begin
if not IsIconic(FHandle) then
begin
NormalizeTopMosts;
SetActiveWindow(FHandle);
DoShowOwnedPopups(False);
if (MainForm <> nil) and (ShowMainForm or MainForm.Visible)
and IsWindowEnabled(MainForm.Handle) then
begin
SetWindowPos(FHandle, MainForm.Handle, MainForm.Left, MainForm.Top,
MainForm.Width, 0, SWP_SHOWWINDOW);
DefWindowProc(FHandle, WM_SYSCOMMAND, SC_MINIMIZE, 0);
end else
ShowWinNoAnimate(FHandle, SW_MINIMIZE);
if Assigned(FOnMinimize) then FOnMinimize(Self);
end;
end;