9.1. Menus

CMenu *menu;
menu = GetMenu()->GetSubMenu(0);

How can I get a pointer to the menu bar to update the menu?ANSWER:

AfxGetApp()->m_pMainWnd->GetMenu()->GetSubMenu(n);

[email protected], Mitch Mlinar, 6/8/95

9.1.2. How do I implement a right-mouse popup-menu?

///////////////////////////////////////////////////////////////////
// WM_RBUTTONDOWN handler.
//
// Trap this message and display the button properties popup menu.
// The main frame receives the popup menu messages. This allows the
// status bar to be updated with the help text.
// ///////////////////////////////////////////////////////////////////
void CAppButton::OnRButtonDown(UINT flags, CPoint point)
{
    CMenu menu;
    CMenu *submenu;
    // load the menu
    menu.LoadMenu(IDR_LAUNCH);
    // get the popup menu
    submenu = menu.GetSubMenu(0);
    // convert to screen coordinates
    ClientToScreen(&point);
    // post the menu
    submenu->TrackPopupMenu(TPM_LEFTALIGN | TPM_RIGHTBUTTON,
                            point.x, point.y,
                            AfxGetApp()->m_pMainWnd,NULL);
}

[email protected], programmer.win32, 7/12/95

It's better to use RBUTTONUP instead, however right-clicking on dialog controls doesn't generate RBUTTONUP and RBUTTONDOWN messages.

If it's necessary to treat this situation too, a program have to catch WM_PARENTNOTIFY message in Win3.x and WinNT and WM_CONTEXTMENU in Windows 95. Here's a code:

// May be dialog too:
BEGIN_MESSAGE_MAP(CMyPropertyPage, CPropertyPage)
    //{{AFX_MSG_MAP(CMyPropertyPage)
    ON_WM_RBUTTONUP()
    ON_WM_PARENTNOTIFY()
    ON_MESSAGE(WM_CONTEXTMENU, OnContextMenu)
    //}}AFX_MSG_MAP
END_MESSAGE_MAP()

 

void CMyPropertyPage::OnRButtonUp(UINT nFlags, CPoint point)=20
{
    PopupMenu (&point);
}

void CMyPropertyPage::OnParentNotify(UINT message, LPARAM lParam)
{
    if (message !=3D WM_RBUTTONDOWN)
        CPropertyPage::OnParentNotify(message, lParam);
    else
    {
        CPoint pt(LOWORD(lParam),HIWORD(lParam));
        PopupMenu (&pt);
    }
}

LONG CMyPropertyPage::OnContextMenu (UINT wParam, LONG lParam)
{
    CPoint pt(LOWORD(lParam),HIWORD(lParam));
    ScreenToClient (&pt);
    PopupMenu (&pt);
    return 0;
}

//*****************************************************************

void CMyPropertyPage::PopupMenu(CPoint* pt)
{
    ASSERT(m_idContextMenu !=3D 0);
    ASSERT(nSubMenu >=3D 0);
    ClientToScreen (pt);
    CMenu FloatingMenu;
    VERIFY(FloatingMenu.LoadMenu(ID_POPUP_MENU));
    CMenu* pPopupMenu =3D FloatingMenu.GetSubMenu (0);
    ASSERT(pPopupMenu !=3D NULL);
    pPopupMenu->TrackPopupMenu (TPM_LEFTALIGN | TPM_RIGHTBUTTON,=20
                                pt->x, pt->y, this);
}

[email protected] - via email, 10/15/95

9.1.3. How do I dynamically change the mainframe menu?

CMenu newMenu;
newMenu.LoadMenu (IDR_MENU1);
AfxGetMainWnd()->SetMenu( &newMenu );
AfxGetMainWnd()->DrawMenuBar();
newMenu.Detach ();

Arun Rao, MSMFC, 6/27/95

9.1.4. How do I 'attach' a menu to a window's creation/destruction?

{Note the original question talked about dialogs, but you can interpolate this code to any kind of window that you want to have change the menu.}

One of the ways to do this is as follows……

Declare a variable CMenu pNewMenu in one of the dialog class.

Handle the WM_INITDIALOG and WM_CLOSE messages in the dialog class as follows.

 

BOOL CMydlg::OnInitDialog()
{
    CDialog::OnInitDialog();
    // Load the IDR_MYFRAME menu
    pNewMenu = new CMenu;
    pNewMenu->LoadMenu(IDR_MYFRAME);
    // Set the mainframe menu to mainframe.
    ((CMainFrame *)AfxGetMainWnd())->SetMenu(pNewMenu);
    return TRUE;
}

And

void CMydlg::OnClose()
{
    // Detach the previous HMenu handle from the object.
    pNewMenu->Detach();
    pNewMenu->LoadMenu(IDR_MAINFRAME);
    // Restore the mainframe menu.
    ((CMainFrame *)AfxGetMainWnd())->SetMenu(pNewMenu);
    CDialog::OnClose();
}

If there are other methods of closing the dialog (example- By clicking a button in the Dialog), then The code given above in OnClose handler, must be put in the button click handler.

Sanjeev Kumar, MSMFC, 6/23/95

IDR_WHAT_IS_THIS_MENU     MENU    DISCARDABLE

BEGIN

    BEGIN

        POPUP "a"

        BEGIN

            MENUITEM "What's this?", ID_WHAT_IS_THIS

        END

    END

END

2. Add to your dialog a right-click handler (OnRButtonDown) with menu IDR_WHAT_IS_THIS_MENU. You need to store the point of the last click in some variable - for example

CPoint m_cLastRClickPoint;

 

and store here the client coordinates of the last right click.

3. Put the following code into your dialog class (or probably the parent class of all your dialogs):

BEGIN_MESSAGE_MAP(CMyDialog, CDialog)

    //{{AFX_MSG_MAP(CMyDialog)

    // whatever

    //}}

    ON_COMMAND(ID_WHAT_IS_THIS, OnWhatIsThis)

END_MESSAGE_MAP()

 

void CMyDialog::OnWhatIsThis()

{

    CWnd* pControl = ChildWindowFromPoint (m_cLastRClickPoint);

   

    // if the click wasn't on one of the controls - open help for dialog

    if (pControl == NULL || pControl->m_hWnd == m_hWnd)

        WinHelp (HID_BASE_RESOURCE + m_nIDHelp, HELP_CONTEXTPOPUP);

    else

        WinHelp (HID_BASE_CONTROL + pControl->GetDlgCtrlID(), HELP_CONTEXTPOPUP);

}

 

- and finally add the following lines to the makehelp.bat file:

 

echo. >>hlp\wr.hm

echo // Controls (IDC_*) >>hlp\wr.hm

makehm IDC_,HIDC_,0x50000 resource.h >>hlp\wr.hm

This wires everything to your help system.

Poul A. Costinsky ([email protected]).