Access Windows Controls from another class or window

Question

In an MFC program I am trying to access controls that are in one window (class) from another (sibling or daughter) window with code in a different .cpp file. Typically you access a control with a DDX_Control variable defined in the class .cpp file.

DDX_Control(pDX, IDC_STATUS, m_Status); 

The code for the other window is in a different file, so I don’t have access to the control variable (m_Status). What I have done is used FindWindow to find the main window, then GetDlgItem to find the control I am interested in:

CWnd * tmpWnd = CWnd::FindWindow(NULL,"MainWindow");  // find the main dialog box
CStatic * tmpStatus = (CStatic*) tmpWnd->GetDlgItem(IDC_Status);
tmpStatus->SetWindowText(“Status Report);

This works fine in the debugger, but fails when executed outside the debugger. FindWindow gets the window ID correctly, but GetDlgItem returns null.

Ideally I’d like to access the control variable (m_Status) from the other window, but I don’ know how to do so. I understand the GetDlgItem is less than ideal under any circumstance.

One solution would be to send a message to the main window class and tell it what to do, but I’d have to have a routine to handle each control and know how to handle whatever kind of data I am sending.

Is there a “right” way to do this? Thank you

The ultimate answer is to cast to the original class:

((CspDlg *)AfxGetMainWnd())->m_Status.SetWindowText("Report");

Answer 1

Since you created the "main" window you have an object or pointer for it. Or, you can call AfxGetMainWnd() to get a pointer to it. Then you can use that to access a public member such as m_Status. All of your windows are interconnected and it should not be necessary to use FindWindow to find any window in your own program.

The fact that some variables may be defined in another file is not relevant. That can be handled with suitable use of #include "theotherfile.h" and object pointers/references.