将透明边框设置为CComboBox控件

Question

我正在尝试设置CComboBox控件的透明边框。对于像CEdit这样的其他控件，可以使用控件属性做到这一点，但我找不到任何针对CComboBox的解决方案。我希望结果如图所示。

​

​

Answer 1

我找到了一小段代码，希望能对你有所帮助：

// YourComboBox.h : header file
class CYourComboBox : public CComboBox
{
public:
    CEdit      m_edit;
    CListBox   m_listbox;

protected:
    afx_msg HBRUSH OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor);
    afx_msg void OnDestroy();
    ...
};

// YourComboBox.cpp : implementation file
HBRUSH CYourComboBox::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
    if (nCtlColor == CTLCOLOR_EDIT)
    {
        //Edit control
        if (m_edit.GetSafeHwnd() == NULL)
            m_edit.SubclassWindow(pWnd->GetSafeHwnd());
    }
    if (nCtlColor == CTLCOLOR_LISTBOX)
    {
        //ListBox control
        if (m_listbox.GetSafeHwnd() == NULL)
            m_listbox.SubclassWindow(pWnd->GetSafeHwnd());
    }

    RemoveEditBorder();

    HBRUSH hbr = CComboBox::OnCtlColor(pDC, pWnd, nCtlColor);
    return hbr;
}

void CYourComboBox::OnDestroy()
{
    if (m_edit.GetSafeHwnd() != NULL)
        m_edit.UnsubclassWindow();
    if (m_listbox.GetSafeHwnd() != NULL)
        m_listbox.UnsubclassWindow();

    CComboBox::OnDestroy();
}

void CYourComboBox::RemoveEditBorder()
{
    m_edit.ModifyStyle(WS_BORDER, 0);
}