This article shows the use of a Push button with a drop down menu, similar to
the one found in the Office 2000 suite. The code is encapsulated in a MFC class.
The class itself is derived from a CButton class, by deriving from this class
most of the button behavior is supplied.
The main core of the code is the drawing routine draw the button and its
behavior. Also there is extensive use of mouse trapping code.
The public interface to access the class is shown here...
BOOL Create( LPCTSTR lpszCaption, DWORD dwStyle,
const RECT& rect, CWnd* pParentWnd, UINT nID );
BOOL SetButtonImage(UINT nResourceId, COLORREF crMask);
BOOL AddMenuItem(UINT nMenuId,const CString strMenu, UINT nFlags);
These functions create the class, set the bitmap for the button and add menu
items for the drop menu menu.
The bitmap must be added as a bitmap resource in the class and its probably
best to use the standard toolbar button size (16x15 pixels).
The color reference for the mask is usually
Menu items are added to the menu button by the
function. You'll need to create a resource symbol and use the relevant menu
flags found in the Windows API under menus (Beyond the scope of this document).
Command handlers are then added to the parent windows message map (see the code
In the sample shown there the button is constructed in the
OnInitDialog handler. The button is created as a Window, but could
quite easy be changed to a subclassed dialog item.
There is room for improvement in the class;
ModifyMenuItem could be added and the
could be modified to replace a current image, unfortunately project deadlines
prevent me adding this functionality.
- 29 July 2000 - updated source and demo
- 4 July 2003 - update source and demo