Advanced MFC Programming

Chapter 3. Splitter Window
Sample application 3.1\Sdi\Spw demonstrates how to implement splitter window. It is generated by
Application Wizard, with all settings set to default ones. Four main classes used to implement the
application are CSpwApp, CMainFrame, CSpwDoc and CSpwView.
Each pane of the splitter window must be attached with a view in order to make it work. The view
could be implemented by deriving class from any of the standard view classes: CView, CScrollView,
CRichEditView, CListView, CTreeView etc. In the sample, besides the default view CSpwView created by
the Application Wizard, two other classes are derived from CFormView and CEditView, which will be used
to implement different panes of the splitter window.
Class CFormView is a standard MFC class that can be used to create view window from dialog
template. A CFormView class must have a corresponding dialog template resource, which will be used to
create the view. To implement a form view, we must first design dialog template, then derive a new class
from CFormView.
In the sample, the dialog template used to implement the form view is IDD_DIALOG_VIEW. Its styles are
set to “Child” and “No border”, this is exactly the same with that of dialog bar (This is because both splitter
window and dialog bar must be child windows). The dialog template contains a static text control and a
multiple-line edit box. By double clicking on the dialog template resource, we will be prompted to add a
new class for it. In this case the template resource ID will be automatically selected to be used by the new
class. In the sample application, the new class is named CSpwFView. If the dialog template is not open when
adding this new class, we must select the dialog ID by ourselves (Figure 3-2).
Input the new
class name
Select the header and
implementation file name
Select base class
Figure 3-2. Derive class from CFormView
If the dialog template resource
is not open, we must select the
ID manually
The other pane of the splitter window is implemented using edit view. The new class for this window
is derived from CEditView, and its name is CSpwEView.
To split a window, we need to call function CSplitterWnd::CreateStatic(…), which has five
parameters:
BOOL CSplitterWnd::CreateStatic
(
CWnd *pParentWnd, int nRows, int nCols,
DWORD dwStyle=WS_CHILD | WS_VISIBLE,
UINT nID=AFX_IDW_PANE_FIRST
);
The first parameter pParentWnd is a CWnd type pointer that points to the parent window. Because a
splitter window is always the child of frame window, this parameter can not be set to NULL. The second
and third parameters specify the number of rows and columns the splitter window will have. The fourth
parameter dwStyle specifies the styles of splitter window, whose default value is WS_CHILD | WS_VISIBLE.
The fifth parameter, nID, identifies which splitter window is being created. This is necessary because
within one frame window, we can create several nested splitter windows. For the root splitter window (The
splitter window whose parent window is the frame window), this ID must be AFX_IDW_PANE_FIRST. For
other nested splitter windows, this ID need to be obtained from the parent splitter windows by calling
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