Advanced MFC Programming

Chapter 1. Tool Bar and Dialog Bar
variable of class CWinApp. In MFC, every application has a CWinApp derived class, which contains a pointer
m_pMainWnd pointing to the mainframe window. For any application, the pointer to the CWinApp object can
be obtained anywhere in the program by calling function AfxGetApp(). Using this method, we can easily
find the mainframe window of any MFC application.
Because the application supports status bar and tool bar, part of its client area may be covered by the
control bar. So we need to deduct the covered area when calculating the dimension of the client area. For
this purpose, in CMainFrame, function CWnd::GetClientRect(…) is overridden. Within the overridden
function, the client area is adjusted if either the status bar or the tool bar is present:
void CMainFrame::GetClientRect(LPRECT lpRect)
{
CRect rect;
}
CFrameWnd::GetClientRect(lpRect);
if(m_wndToolBar.IsWindowVisible())
{
m_wndToolBar.GetClientRect(rect);
lpRect->bottom-=rect.Height();
}
if(m_wndStatusBar.IsWindowVisible())
{
m_wndStatusBar.GetClientRect(rect);
lpRect->bottom-=rect.Height();
}
Now back to MCDialogBar::CalcDynamicLayout(…) implementation. After obtaining the size of
mainframe window’s client area, we examine LM_VERTDOCK and LM_HORZDOCK bits of dwMode parameter to
see if the docking size is being inquired. If so, we further examine LM_HORZ bit to see if we should return
horizontally docked size or vertically docked size. We return different sizes for different cases. For all other
conditions, we just return the default implementation of the base class.
Using the New Class
To use this class, first we need to declare a MCDialogBar type variable in class CMainFrame. We also
need to make sure that the header file of this class is included. In the sample application, this new variable
is m_wndDialogBar. Then, as we have experienced many times, we need to create the window of the dialog
bar in function CMainFrame::OnCreate(…). When doing this, we need to specify CBRS_SIZE_DYNAMIC flag
in order to let the dialog bar be resized dynamically. Then we can call CDialogBar::EnableDocking(…),
CDialogBar::SetBarStyle(…) and CMainFrame::DockControlBar(…) to set styles and implement
docking.
Now we can compile and execute the new project. Originally, the dialog bar is docked at the bottom
border of the frame window. We may drag and dock it to any other border, or make it floating. As we do
this, the dimension of the dialog bar will be adjusted automatically to suit different docking styles. Also,
the edit control contained in the dialog bar will be resized dynamically according to the change on the
dialog bar.
1.10. Adding Flyby and Tool Tip
Flyby and tool tip are two very nice features that can be added to both tool bar and dialog bar. If we
enable these features, when the user moves mouse cursor over a control contained in tool bar or dialog bar
and stay there for a while, a describing text about this control will appear on the status bar (It is called
Flyby). At the same time, a small window with a short description will pop up (It is called Tool Tip. See
Figure 1-12 for two types of controls).
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