第16单元多文档界面程序 339 CScrollView:: OnLButtonDown(nFlags, point) CClientDC dc(this) m pointFrom =m pointTo point: cAptured true void CMy 1603View: OnL But tonUp qUiNT nFlags, CPoint point CScrollview:: OnLButtonUp (n Flags, point) CMy 1603Doc* pDoc GetDocumento ASSERT VALID (pDoc) CClientDC dc(this) NpR m cAptured FAlSE: Point org GetScrollPosition O Doc->m lineList lpDoc->m nCount]= CLine(m pointFromtorg m pointTotorg, m colorCurr, m nCurr Width) pDoc->SetModifiedFlago pDoc->UpdateAllViews(this) Invalidate o void CMy 1603View:: On MouseMove(UINT nFlags, CPoint point) CScrollView:: On MouseMove (nFlags, point) if(m cAptured) OnPre dc (&de第 16 单元 多文档界面程序 339 CScrollView::OnLButtonDown(nFlags, point); CClientDC dc(this); OnPrepareDC(&dc); dc.DPtoLP(&point); m_pointFrom = m_pointTo = point; SetCapture(); m_bCaptured = TRUE; } void CMy1603View::OnLButtonUp(UINT nFlags, CPoint point) { CScrollView::OnLButtonUp(nFlags, point); if(m_bCaptured) { CMy1603Doc* pDoc = GetDocument(); ASSERT_VALID(pDoc); CClientDC dc(this); OnPrepareDC(&dc); dc.DPtoLP(&point); m_pointTo = point; m_bCaptured = FALSE; ReleaseCapture(); CPoint org = GetScrollPosition(); pDoc->m_lineList[pDoc->m_nCount] = CLine(m_pointFrom+org, m_pointTo+org, m_colorCurr, m_nCurrWidth); pDoc->m_nCount++; pDoc->SetModifiedFlag(); pDoc->UpdateAllViews(this); Invalidate(); } } void CMy1603View::OnMouseMove(UINT nFlags, CPoint point) { CScrollView::OnMouseMove(nFlags, point); if(m_bCaptured) { CClientDC dc(this); OnPrepareDC(&dc); dc.DPtoLP(&point);