最大化就可以了
//定义
procedure WMSize(var message: TWMSize); message WM_SIZE;
//始终保持窗体最大化
procedure TFmFlowMain.WMSize(var message: TWMSize);
var
H : HWND;
Size: Longint;
begin
if Tag <> NOSIZETAG then
begin
if (message.SizeType = SIZE_MINIMIZED) or (message.SizeType = SIZE_RESTORED) then
begin
H := SendMessage(fmMainForm.ClientHandle, WM_MDIGETACTIVE, 0, 0);
SHOWWINDOW(Handle, SW_MAXIMIZE);
SendMessage(fmMainForm.ClientHandle, WM_MDIACTIVATE, Word(H), 0);
end
else
inherited;
end;
end;