请问MDI程序，如何限制一个Doc只开一个子窗口？

[nethermit]

我想实现的效果是如果没有这个Doc的窗口就创建一个，如果已经存在就激活那个窗口，请教各位如何实现？

[wistaria]

在CMDI...View映射菜单项ID_FILE_NEW消息,不加入任何代码就行了.

[vccsdn]

OnFileNew 中
POSITION pos = GetFirstViewPosition();
if (pos != NULL)
{
CView* pView = GetNextView(pos);
pView->UpdateWindow();
}

[nethermit]

不是这个意思，我程序里面有很多MDIDocTemplate，当新开一个窗口的时候，要判断当前的子窗口是否已经有了这个Doc，如果有了，就激活它，如果没有就创建一个。每一个Doc要判断自己的窗口。

[wistaria]

枚举文档对应的视图.也许对你有用
CView* pView;
POSITION pos=pDoc->GetFirstViewPosition();
while(pos!=NULL)
{
pView=pDoc->GetNextView(pos);
if(pView->IsKindOf(RUNTIME_CLASS(C...View)))
{
....//
}
}

[蒋晟]

CDocument* CMyApp::CreateOrShow(CMultiDocTemplate* pDocTemplate)
{
POSITION posDoc=pDocTemplate->GetFirstDocPosition();
CDocument* pDocument =NULL;
if(posDoc!=NULL){
pDocument =pDocTemplate->GetNextDoc(posDoc);
//To get the first view in the list of views:

POSITION posView = pDocument ->GetFirstViewPosition();
CView* pFirstView = pDocument ->GetNextView(posView);
ASSERT(pFirstView !=NULL);
pFirstView ->GetParentFrame()->GetLastActivePopup()->BringWindowToTop();
return pDocument;
}
else{
pDocument =pDocTemplate->CreateNewDocument();
if (pDocument == NULL)
{
TRACE0("CDocTemplate::CreateNewDocument returned NULL.\n");
AfxMessageBox(AFX_IDP_FAILED_TO_CREATE_DOC);
return NULL;
}
ASSERT_VALID(pDocument);
CString strTitle;
pDocTemplate->GetDocString(strTitle,CDocTemplate::windowTitle);
pDocument->SetTitle(strTitle);
BOOL bAutoDelete = pDocument->m_bAutoDelete;
pDocument->m_bAutoDelete = FALSE; // don't destroy if something goes wrong
CFrameWnd* pFrame = pDocTemplate->CreateNewFrame(pDocument, NULL);
pDocument->m_bAutoDelete = bAutoDelete;
if (pFrame == NULL)
{
AfxMessageBox(AFX_IDP_FAILED_TO_CREATE_DOC);
delete pDocument; // explicit delete on error
return NULL;
}
ASSERT_VALID(pFrame);
pDocTemplate->InitialUpdateFrame(pFrame ,pDocument,TRUE);
pFrame->ShowWindow(SW_SHOWMAXIMIZED);
}
return pDocument ;
}

[floattofool]

UP!

[nethermit]

呵呵，来晚了，我已经在程序员合订本2001上面找到答案了，不过还是很感谢各位的帮忙，星期一等我试完给分！ :)

[nethermit]

那么还要激活它，麻烦啊

[nethermit]

虽然我已经在程序员合订本2001上面找到答案，不过还是要多谢jiangsheng(蒋晟.Net)，下面是我写的代码，见笑，顺便给分！

BOOL CMainFrame::FntCreateOrShow(CMultiDocTemplate* pDocTemplate)
{
POSITION posDoc=pDocTemplate->GetFirstDocPosition();
CDocument* pDocument =NULL;
if (posDoc!=NULL)
{
pDocument =pDocTemplate->GetNextDoc(posDoc);
POSITION posView = pDocument ->GetFirstViewPosition();
CView* pFirstView = pDocument ->GetNextView(posView);
ASSERT(pFirstView !=NULL);
pFirstView->GetParentFrame()->GetLastActivePopup()->BringWindowToTop();//激活视图
return TRUE;
}
else
{
pDocTemplate->OpenDocumentFile(NULL);
}
return FALSE;
}