修改CDialog模态对话框函数DoModal 使对话框显示可以受WS_VISIBLE风格控制

调试追踪DoModal的执行过程发现对话框显示的位置在 CWnd::RunModalLoop(DWORD dwFlags)中
BOOL bShowIdle = (dwFlags & MLF_SHOWONIDLE) && !(GetStyle() & WS_VISIBLE);
……
if (bShowIdle)
{
 ShowWindow(SW_SHOWNORMAL); //这里显示出来了
 UpdateWindow();
 bShowIdle = FALSE;
}

而CWnd::RunModalLoop(DWORD dwFlags)没有提供重载接口我们只能修改传入的参数
再返回到DoModal中我们发现 DWORD dwFlags = MLF_SHOWONIDLE;
于是我们修改DWORD dwFlags = 0;// MLF_SHOWONIDLE;
即达到了模态对话框也受WS_VISIBLE风格控制的效果

 

int CCcDlg::DoModal() { // TODO: Add your specialized code here and/or call the base class // can be constructed with a resource template or InitModalIndirect ASSERT(m_lpszTemplateName != NULL || m_hDialogTemplate != NULL || m_lpDialogTemplate != NULL); // load resource as necessary LPCDLGTEMPLATE lpDialogTemplate = m_lpDialogTemplate; HGLOBAL hDialogTemplate = m_hDialogTemplate; HINSTANCE hInst = AfxGetResourceHandle(); if (m_lpszTemplateName != NULL) { hInst = AfxFindResourceHandle(m_lpszTemplateName, RT_DIALOG); HRSRC hResource = ::FindResource(hInst, m_lpszTemplateName, RT_DIALOG); hDialogTemplate = LoadResource(hInst, hResource); } if (hDialogTemplate != NULL) lpDialogTemplate = (LPCDLGTEMPLATE)LockResource(hDialogTemplate); // return -1 in case of failure to load the dialog template resource if (lpDialogTemplate == NULL) return -1; // disable parent (before creating dialog) HWND hWndParent = PreModal(); //AfxUnhookWindowCreate(); BOOL bEnableParent = FALSE; if (hWndParent != NULL && ::IsWindowEnabled(hWndParent)) { ::EnableWindow(hWndParent, FALSE); bEnableParent = TRUE; } TRY { // create modeless dialog //AfxHookWindowCreate(this); if (CreateDlgIndirect(lpDialogTemplate, CWnd::FromHandle(hWndParent), hInst)) { if (m_nFlags & WF_CONTINUEMODAL) { // enter modal loop DWORD dwFlags = 0;// MLF_SHOWONIDLE; if (GetStyle() & DS_NOIDLEMSG) dwFlags |= MLF_NOIDLEMSG; VERIFY(RunModalLoop(dwFlags) == m_nModalResult); } // hide the window before enabling the parent, etc. if (m_hWnd != NULL) SetWindowPos(NULL, 0, 0, 0, 0, SWP_HIDEWINDOW| SWP_NOSIZE|SWP_NOMOVE|SWP_NOACTIVATE|SWP_NOZORDER); } } CATCH_ALL(e) { { e->Delete(); }//DELETE_EXCEPTION(e); m_nModalResult = -1; } END_CATCH_ALL if (bEnableParent) ::EnableWindow(hWndParent, TRUE); if (hWndParent != NULL && ::GetActiveWindow() == m_hWnd) ::SetActiveWindow(hWndParent); // destroy modal window DestroyWindow(); PostModal(); // unlock/free resources as necessary if (m_lpszTemplateName != NULL || m_hDialogTemplate != NULL) UnlockResource(hDialogTemplate); if (m_lpszTemplateName != NULL) FreeResource(hDialogTemplate); return m_nModalResult; // return CDialog::DoModal(); }