Advanced MFC Programming

Chapter 6. Dialog Box
wndA.GetWindowRect(rect);
wndB.ScreenToClient(rect);
Sample
When the user resizes a window, a WM_SIZE message will be sent to that window. We can handle this
message to resize and move the controls contained in the dialog template.
Sample 6.6\DB demonstrates how to resize the common controls contained in the form view
dynamically. It is a standard SDI application generated from the Application Wizard. When generating the
application, CFormView is selected as the base class of the view in the last step. After the application is
generated, the following controls are added to the dialog template: an edit box, a static group control, two
buttons. The IDs of these controls are IDC_EDIT, IDC_STATIC_GRP, IDC_BUTTON_A and IDC_BUTTON_B
respectively.
If we compile and execute the application at this point, the application will behave awkwardly because
if we resize the window, the sizes/positions of the controls will not change, this may make the window not
well balanced (Figure 6-6).
Figure 6-6. The form view is not well balanced
We need to remember the original sizes and positions of the embedded controls and base their new
sizes and positions on them. In the sample, four CRect type variables are declared in class CDBView for this
purpose:
……
……
class CDBView : public CFormView
{
protected:
CRect m_rectA;
CRect m_rectB;
CRect m_rectEdit;
CRect m_rectStaticGrp;
BOOL m_bSizeAvailable;
}
Also, a Boolean type variable m_bSizeAvailable is added to indicate if the original positions and sizes
of the controls have been recorded.
There is no OnInitDialog() member function for class CFormView. The similar one is CView::
OnInitialUpdate(). This function is called when the view is first created and is about to be displayed. We
can record the positions and sizes of the controls in this function.
Variable m_bSizeAvailable is initialized to FALSE in the constructor of class CDBView:
CDBView::CDBView()
: CFormView(CDBView::IDD)
{
//{{AFX_DATA_INIT(CDBView)
155