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//我用图形模式中的 SetROP2(R2_XORPEN)来设置虚框模式
//通调用DrawFocusRect()函数来画!
//问题是从左上角右下角可以画虚框的,但是由右到左,下到上就没有虚框了!这是什么原因呢?
//代码如下:
void CGraphicView::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
m_ptOrigin=point;
m_bDraw=TRUE;
m_pre.left=point.x;
m_pre.top=point.y;
m_pre.right=point.x;
m_pre.bottom=point.y;
m_new.left=point.x;
m_new.top=point.y;
m_new.right=point.x;
m_new.bottom=point.y;
CView::OnLButtonDown(nFlags, point);
}
void CGraphicView::OnLButtonUp(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
m_bDraw=FALSE;
CClientDC dc(this);
CPen pen(PS_SOLID,3,RGB(255,0,0));
dc.SelectObject(&pen);
dc.SetROP2(R2_COPYPEN);
switch(m_nDrawType)
{
case 1:
dc.SetPixel(point,RGB(255,0,0));
break;
case 2:
dc.MoveTo(m_ptOrigin);
dc.LineTo(point);
break;
case 3:
dc.Rectangle(CRect(m_ptOrigin,point));
break;
case 4:
dc.Ellipse(CRect(m_ptOrigin,point));
break;
}
CView::OnLButtonUp(nFlags, point);
}
void CGraphicView::OnMouseMove(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
if(m_bDraw)
{
CClientDC dc(this);
dc.SetROP2(R2_XORPEN); //设置虚框模式
dc.DrawFocusRect(&m_pre);
m_new.right=point.x;
m_new.bottom=point.y;
dc.DrawFocusRect(&m_new);//画新矩形
m_pre.right=m_new.right;
m_pre.bottom=m_new.bottom;
dc.SetROP2(R2_WHITE);
}
CView::OnMouseMove(nFlags, point);
}
void CGraphicView::OnMouseMove(UINT nFlags, CPoint point)
{
if(m_bDraw)
{
CClientDC dc(this);
dc.SetROP2(R2_XORPEN); //设置虚框模式
dc.DrawFocusRect(&m_pre);
if (m_ptOrigin.x < point.x)
{
m_new.left = m_ptOrigin.x;
m_new.right = point.x;
}
else
{
m_new.left = point.x;
m_new.right = m_ptOrigin.x;
}
if (m_ptOrigin.y < point.y)
{
m_new.top = m_ptOrigin.y;
m_new.bottom = point.y;
}
else
{
m_new.top = point.y;
m_new.bottom = m_ptOrigin.y;
}
dc.DrawFocusRect(&m_new);//画新矩形
m_pre = m_new;
dc.SetROP2(R2_WHITE);
}
CView::OnMouseMove(nFlags, point);
}