Having trouble getting a handle to a Dockable Pane C++ - c++

Question

I created a multi doc ribbon based MFC application through the MFC Wizard. Im trying to get a handle to m_wndFileView to update its view. I know there are several ways to do it but Im not understanding why the method Im using is not working. Soooo to start
class CMainFrame : public CMDIFrameWndEx
{
...
CFileView m_wndFileView;
CPropertiesWnd m_wndProperties;
...
}
class CFileView : public CDockablePane
{
...
protected:
CViewTree m_wndFileView;
...
};
class CPropertiesWnd : public CDockablePane
{
...
protected:
CMFCPropertyGridCtrl m_wndPropList;
...
};
The main frame is created from MAINAPPLICATION.cpp
// create main MDI Frame window
CMainFrame* pMainFrame = new CMainFrame;
if (!pMainFrame || !pMainFrame->LoadFrame(IDR_MAINFRAME))
{
delete pMainFrame;
return FALSE;
}
m_pMainWnd = pMainFrame;
// call DragAcceptFiles only if there's a suffix
// In an MDI app, this should occur immediately after setting m_pMainWnd
// Enable drag/drop open
m_pMainWnd->DragAcceptFiles();
// Parse command line for standard shell commands, DDE, file open
CCommandLineInfo cmdInfo;
ParseCommandLine(cmdInfo);
// Enable DDE Execute open
EnableShellOpen();
RegisterShellFileTypes(TRUE);
// Dispatch commands specified on the command line. Will return FALSE if
// app was launched with /RegServer, /Register, /Unregserver or /Unregister.
if (!ProcessShellCommand(cmdInfo))
return FALSE;
// The main window has been initialized, so show and update it
pMainFrame->ShowWindow(m_nCmdShow);
pMainFrame->UpdateWindow();
MainFrm.cpp creates these two panes:
// Create file view
CString strFileView;
bNameValid = strFileView.LoadString(IDS_FILE_VIEW);
ASSERT(bNameValid);
if (!m_wndFileView.Create(strFileView, this, CRect(0, 0, 200, 200), TRUE, ID_VIEW_FILEVIEW, WS_CHILD | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN | CBRS_LEFT| CBRS_FLOAT_MULTI))
{
TRACE0("Failed to create File View window\n");
return FALSE; // failed to create
}
// Create properties window
CString strPropertiesWnd;
bNameValid = strPropertiesWnd.LoadString(IDS_PROPERTIES_WND);
ASSERT(bNameValid);
if (!m_wndProperties.Create(strPropertiesWnd, this, CRect(0, 0, 200, 200), TRUE, ID_VIEW_PROPERTIESWND, WS_CHILD | WS_VISIBLE | WS_CLIPSIBLINGS | WS_CLIPCHILDREN | CBRS_RIGHT | CBRS_FLOAT_MULTI))
{
TRACE0("Failed to create Properties window\n");
return FALSE; // failed to create
}
From MAINAPPLICATION.cpp, I can access the properties pane through
CWnd * pwnd = ((CWnd*)(AfxGetApp()->m_pMainWnd));
CPropertiesWnd * pPropertiesWnd = (CPropertiesWnd*)pwnd->GetDlgItem(ID_VIEW_PROPERTIESWND);
CMFCPropertyGridCtrl * m_wndPropList = (CMFCPropertyGridCtrl *)pPropertiesWnd->GetDlgItem(2);
but for some reason I cannot access the fileview pane with
CWnd * pwnd = ((CWnd*)(AfxGetApp()->m_pMainWnd));
CFileView * pFileViewWnd = (CFileView*)pwnd->GetDlgItem(ID_VIEW_FILEVIEW);
CViewTree * m_wndFileView= (CViewTree*)pFileViewWnd ->GetDlgItem(4);
the (CFileView*)pwnd->GetDlgItem(ID_VIEW_FILEVIEW); returns NULL
please help. This is driving me crazy. In the end I can modify the m_wndPropList but not the m_wndFileView because I cannot get a handle to pFileViewWnd. Two panes created in the same way cannot be accessed in the same way. Why? If more code is needed, let me know. Thanks.

Answer 1

You should create a inline getters in CMainFrame class like this:
CFileView& GetFileViewPane()
{
return m_wndFileView;
}
CPropertiesWnd& GetPropsPane()
{
return m_wndProperties;
}
After that you can access those windows just like this:
CMainFrame* pMainFrame = DYNAMIC_DOWNCAST(CMainFrame, AfxGetMainWnd());
if (pMainFrame && pMainFrame->GetSafeHwnd()) // sanity check
{
pMainFrame->GetFileViewPane().DoStuff();
}

Answer 2

So #MarkRansom really helped out with the spy++ idea. To get a handle, I had to do the following:
// get CWnd to main window
CWnd * pwnd = ((CWnd*)(AfxGetApp()->m_pMainWnd));
// from spy++ i found that the tabbed panes were in a window called
// "File View" so i found a child window with that title
HWND h = FindWindowExW(pwnd->GetSafeHwnd(), NULL, NULL, L"File View");
// casted it to a tabbedpane pointer
CTabbedPane * pFileViewWn = (CTabbedPane *)CWnd::FromHandle(h);
// mfc wizard did what seems to me as weird naming. to find the docking
// panes i did the same as above but there was no title to this window
HWND hh = FindWindowExW(pFileViewWn->GetSafeHwnd(), NULL, NULL, L"");
// casted that
CDockablePane* pTabbedBar = (CDockablePane*)CWnd::FromHandle(hh);
// was able to find my specific docking pane using a resource id
CFileView * pFileViewWnd = (CFileView*)pTabbedBar->GetDlgItem(ID_VIEW_FILEVIEW);
// was able to find the control i wanted to use using a resource id
CViewTree * m_wndFileView = (CViewTree *)pFileViewWnd->GetDlgItem(4);
HTREEITEM hRoot = m_wndFileView->GetRootItem();
m_wndFileView->InsertItem(name, 2, 2, hRoot);
Going through the code i would think that the logic would be
tabbed pane
File View Dockable Pane
File View controls
Class View Dockable Pane
Class View controls
but somehow another window slide its way in to make
tabbed pane
MYSTERY DOCKABLE WINDOW
File View Dockable Pane
File View controls
Class View Dockable Pane
Class View controls