How to add a gripper to a PropertySheet?

问题:

I have a class derived from CPropertySheet, and i want to insert a "gripper" on the bottom right of the dialog.
my dialog already is resizable, i just can't insert the gripper.

回答1:

I don't know if there are any special APIs to do that. One option is to draw it manually, then override ON_WM_NCHITTEST and return HTBOTTOMRIGHT for gripper's position. For example:

void CMyDialog::OnPaint()
{
    CPaintDC dc(this);
    CRect rc;
    GetClientRect();
    rc.left = rc.right - ::GetSystemMetrics(SM_CXHSCROLL);
    rc.top = rc.bottom - ::GetSystemMetrics(SM_CYVSCROLL);
    HTHEME ht = OpenThemeData(m_hWnd, L"STATUS");
    if (ht)
    {
        DrawThemeBackground(ht, dc, SP_GRIPPER, 0, &rc, 0);
        CloseThemeData(ht);
    }
    else
    {
        dc.DrawFrameControl(rc, DFC_SCROLL, DFCS_SCROLLSIZEGRIP);
    }
}

LRESULT CMyDialog::OnNcHitTest(CPoint point)
{
    CRect rc;
    GetWindowRect(rc);
    rc.left = rc.right - ::GetSystemMetrics(SM_CXHSCROLL);
    rc.top = rc.bottom - ::GetSystemMetrics(SM_CYVSCROLL);
    if (rc.PtInRect(point))
        return HTBOTTOMRIGHT;
    return CDialog::OnNcHitTest(point);
} 

void CMyDialog::OnSize(UINT type, int cx, int cy)
{
    CDialog::OnSize(type, cx, cy);
    Invalidate(TRUE);
}

Add to message map:

ON_WM_PAINT()
ON_WM_NCHITTEST()
ON_WM_SIZE()