Q108896: INFO: Dynamically Disabling/Enabling a Control in a Dialog Box

Article: Q108896
Product(s): Microsoft C Compiler
Version(s): winnt:1.0,2.0,2.1,4.0
Operating System(s): 
Keyword(s): kbCtrl kbDlg kbMFC KbUIDesign kbVC kbDSupport kbGrpDSMFCATL
Last Modified: 07-MAY-2001

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The information in this article applies to:

- The Microsoft Foundation Classes (MFC), used with:
   - Microsoft Visual C++ for Windows, 16-bit edition, versions 1.0, 1.5, 1.51, 1.52 
   - Microsoft Visual C++, 32-bit Editions, versions 1.0, 2.0, 2.1, 4.0 
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This article demonstrates one way to disable or enable a dialog box control
during the execution of a program with the Microsoft Foundation Classes
(MFC). The dialog box uses a dialog box template created by App Studio.

To disable or enable a control in a dialog box, the following steps can be
performed:

1. Create a data member in the dialog box class that maps to a specific control
  (you can use Class Wizard to do this). For example:

        ...
        public:
        CButton     m_button;
        ...

2. Override CWnd::DoDataExchange(CDataExchange *pDX) in the dialog box class and
  call the appropriate DDX routine to hook the Windows control to the dialog
  class data member. For example:

        ...
        protected:
        virtual void DoDataExchange(CDataExchange* pDX);
        ...

        void CMyDlg::DoDataExchange(CDataExchange* pDX)
        {
          CDialog::DoDataExchange(pDX);
          DDX_Control(pDX, IDC_BUTTON1, m_button);
        }

  NOTE: If you use Class Wizard to add a member variable in your dialog box
  class, it does this for you.

3. Call CWnd::EnableWindow() to disable or enable the control when needed. For
  example, you can disable a button when the dialog box is initialized. For
  example:

        CMyDlg::OnInitDialog()
        {
         ...
         m_button.EnableWindow(FALSE);
         ...
        }

  An alternative method is to use the CWnd::GetDlgItem() function to get a CWnd
  * to the control and then call EnableWindow(). For example:

        CMyDlg::OnInitDialog()
         {
          ...
          GetDlgItem(IDC_BUTTON)->EnableWindow(FALSE);
          ...
         }

SUMMARY
=======



Additional query words: kbSweptVC600 kbinf 1.00 1.50 2.00 2.10 2.50 2.51 2.52 3.00 3.10 4.00

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Keywords          : kbCtrl kbDlg kbMFC KbUIDesign kbVC kbDSupport kbGrpDSMFCATL 
Technology        : kbAudDeveloper kbMFC
Version           : winnt:1.0,2.0,2.1,4.0
Issue type        : kbhowto

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