Advanced MFC Programming

Chapter 1. Tool Bar and Dialog Bar
Sample 1.11\Bar supports this new feature, it is based on sample 1.10\Bar. For both tool bar and dialog
bar, a new command is added to the main menu, which can be used to toggle the control bar between on
and off state.
The following shows necessary steps for implementing the new commands:
1) Add two menu items View | Color Bar and View | Dialog Bar to the mainframe menu IDR_MAINFRAME,
whose IDs are ID_VIEW_COLORBAR and ID_VIEW_DIALOGBAR respectively.
1) Use Class Wizard to add WM_COMMAND and UPDATE_COMMAND_UI type message handlers for the above
IDs in class CMainFrame. The newly added functions are CMainFrame::OnViewColorBar(),
CMainFrame:: OnViewDialogBar(), CMainFrame::OnUpdateViewColorBar(…) and CMainFrame::
OnUpdateViewDialogBar(…).
1) Implement four WM_COMMAND type message handlers. The function used to handle WM_COMMAND message
for command ID_VIEW_COLORBAR is implemented as follows:
void CMainFrame::OnViewColorBar()
{
BOOL bShow;
}
bShow=m_wndColorButton.IsWindowVisible() ? FALSE:TRUE;
ShowControlBar(&m_wndColorButton, bShow, FALSE);
To indicate the status of control bars, it is desirable to check the corresponding menu item when the
control bar is available, and remove the check when it becomes hidden. This is exactly the same with the
behavior of the default tool bar IDR_MAINFRAME. In the sample, the menu item states are handled by
trapping message UPDATE_COMMAND_UI and the check is set or removed by calling function
CCmdUI::SetCheck(…). The following is the implementation of one of the above message handlers (see
Chapter 2 for more about menu customization):
void CMainFrame::OnUpdateViewColorBar(CCmdUI* pCmdUI)
{
pCmdUI->SetCheck(m_wndColorButton.IsWindowVisible());
}
It is exactly the same with setting or removing check for a tool bar button.
With the above implementations, the application can be executed again. We can dismiss the control bar
either by executing menu command or by clicking “X” button located at the upper-right corner of the
control bar when it is floating. In both cases, the control bar can be turned on again by executing
corresponding menu command. We can also dock or float the control bar and turn it off, and see if the
original state will remain unchanged after it is turned on later.
Summary:
1. To add an extra tool bar, first we need to add a tool bar resource, then declare a CToolBar type variable
in CMainFrame class. Within function CMainFrame::OnCreate(…), we can call the member functions of
CToolBar and CMainFrame to create the tool bar window and set docking styles.
1. The dialog bar can be added in the same way, however, we need to use dialog-template resource and
class CDialogBar to implement it.
1. We can trap WM_COMMAND message for executing command and trap UPDATE_COMMAND_UI for updating
button state. Use ON_COMMAND and ON_UPDATE_COMMAND_UI macros to implement message mapping.
1. We can use ON_COMMAND_RANGE and ON_UPDATE_COMMAND_UI_RANGE macros to map a contiguous range
of command IDs to one member function.
1. When the size of a tool bar is fixed, we can set TBBS_WRAPPED flag for a button to let the tool bar wrap
after that button.
1. To customize the dynamic layout feature of tool bar and dialog bar, we need to override function
CalcDynamicLayout(…).
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