点BUTTON来改变flag,通过Invalidate(TRUE);触发onpaint
以下代码在onpaint函数内:
CStatic* pWnd = (CStatic*)GetDlgItem(IDC_STATIC1);
CDC* pDC = pWnd->GetDC();
if(flag){
pDC->MoveTo(100,100);
pDC->LineTo(200,200);}问题是:为什么会画不出一条直线呢?
以下代码在onpaint函数内:
CStatic* pWnd = (CStatic*)GetDlgItem(IDC_STATIC1);
CDC* pDC = pWnd->GetDC();
if(flag){
pDC->MoveTo(100,100);
pDC->LineTo(200,200);}问题是:为什么会画不出一条直线呢?
CPen RectPen(PS_DASH,1,0x0000FF);
pDC->SelectObject(&RectPen); 然后再画啊!