Article ID: 174667
Article Last Modified on 11/21/2006
// SuperComboBox.h : header file
class CSuperComboBox : public CComboBox
{
public:
CEdit m_edit;
CListBox m_listbox;
protected:
afx_msg HBRUSH OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor);
afx_msg void OnDestroy();
...
};
// SuperComboBox.cpp : implementation file
HBRUSH CSuperComboBox::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
if (nCtlColor == CTLCOLOR_EDIT)
{
//[ASCII 160][ASCII 160][ASCII 160]Edit control
if (m_edit.GetSafeHwnd() == NULL)
m_edit.SubclassWindow(pWnd->GetSafeHwnd());
}
else if (nCtlColor == CTLCOLOR_LISTBOX)
{
//ListBox control
if (m_listbox.GetSafeHwnd() == NULL)
m_listbox.SubclassWindow(pWnd->GetSafeHwnd());
}
HBRUSH hbr = CComboBox::OnCtlColor(pDC, pWnd, nCtlColor);
return hbr;
}
void CSuperComboBox::OnDestroy()
{
if (m_edit.GetSafeHwnd() != NULL)
m_edit.UnsubclassWindow();
if (m_listbox.GetSafeHwnd() != NULL)
m_listbox.UnsubclassWindow();
CComboBox::OnDestroy();
}
Note that for subclassing to occur, the dialog box must be painted at least
once. There are cases when the dialog box doesn't paint at all (for
example, closing the dialog box before it is displayed, hidden dialog
boxes). This method may not be suitable when access to the subclassed
windows are needed in these cases.
Additional query words: combobox listbox
Keywords: kbcode kbcombobox kbctrl kbhowto kbuidesign KB174667