1。鼠標落下,記錄鼠標的起始位置
void CMyEasyDrawView::On
{
?// TODO: 在此添加消息處理程序代碼和/或調用默認值
?//graph->m_nType=dlg->
?m_bStartDraw = true;
?m_PtPress = m_PtLast = point;
?CView::On
}
2.鼠標抬起,畫圖結束,記錄下畫圖的所有參數
oid CMyEasyDrawView::On
{
?DrawDialog *dlg=CMainFrame::GetDrawTool();
?if (m_bStartDraw)
?{
??// 創建新圖形對象
??EasyGraphics* graph = new EasyGraphics;
??// 對圖形屬性賦值
??graph->m_nType = m_nGraphType;
??graph->m_clrColor =dlg->m_clrColor;
??graph->m_nLineType = dlg->m_nType;
??graph->m_nLineWidth = dlg->m_lineWide;
??graph->m_PtTopLeft = m_PtPress;
??graph->m_PtBottomRight = point;
??// 添加到圖形容器中
??m_GraphAry.Add(graph);
??// 一個繪制結束
??m_bStartDraw = false;
??// 讓視圖重繪
??Invalidate();
?}
?CView::On
}
3.鼠標移動產生的動感
void CMyEasyDrawView::On
{
?if (m_bStartDraw)
?{
??CDC* pDC = GetDC();
??int nDrawMode = pDC->SetROP2(R2_NOTXORPEN);??// 設置為“異或模式”
??DrawDialog* dlg = CMainFrame::GetDrawTool();
??EasyGraphics* graph = new EasyGraphics;???// 臨時繪制對象
??// 對圖形屬性賦值;
??graph->m_nType = m_nGraphType;
??graph->m_clrColor =dlg->m_clrColor;
??graph->m_nLineType = dlg->m_nType;
??graph->m_nLineWidth = dlg->m_lineWide;
??graph->m_PtTopLeft = m_PtPress;
??graph->m_PtBottomRight = m_PtLast;
??DrawGraphics(pDC, graph);?// 擦除上次繪制圖形
??graph->m_PtBottomRight = point;
??DrawGraphics(pDC, graph);?// 繪制新圖形
m_PtLast = point;???// 保存當前鼠標坐標
??pDC->SetROP2(nDrawMode);
??if(graph!=NULL)
??{
???delete graph;
???graph=NULL;
??}
??ReleaseDC(pDC);
?}
?CView::On
}
4.畫圖操作函數
void CMyEasyDrawView::DrawGraphics(CDC* pDC, EasyGraphics* graph)
{
?LOGBRUSH logBrush;
?logBrush.lbStyle = BS_SOLID;
?logBrush.lbColor = graph->m_clrColor;
?CPen pen(graph->m_nLineType |PS_GEOMETRIC|PS_ENDCAP_ROUND,?
??? graph->m_nLineWidth, &logBrush);
?// 選中新的筆對象
?CPen*?oldPen = pDC->SelectObject(&pen);
?
?// 使用透明畫刷
?CBrush* oldBrush = (CBrush*)pDC->SelectStockObject(NULL_BRUSH);
?switch (graph->m_nType)
?{
?case EG_RECT:??
??// 繪制矩形
??pDC->Rectangle(graph->m_PtTopLeft.x,?
??????? graph->m_PtTopLeft.y,
??????? graph->m_PtBottomRight.x,
??????? graph->m_PtBottomRight.y);
??break;
?case EG_CIRCLE:??
??// 繪制橢圓
??pDC->Ellipse(graph->m_PtTopLeft.x,?
????? graph->m_PtTopLeft.y,
????? graph->m_PtBottomRight.x,
????? graph->m_PtBottomRight.y);
??break;
?default:???
??// 繪制直線
??pDC->MoveTo(graph->m_PtTopLeft);
??pDC->LineTo(graph->m_PtBottomRight);
?}
?pDC->SelectObject(oldPen);
?pDC->SelectObject(oldBrush);
}
5.初始設置
void CMyEasyDrawView::On
{
?CMyEasyDrawDoc* pDoc = GetDocument();
?ASSERT_VALID(pDoc);
?if (!pDoc)
??return;
?// TODO: 在此處為本機數據添加繪制代碼
?CRect rect;
?GetClientRect(rect);
?CDC memDC;
?CBitmap MemBitmap;
?//設備描述表初始話
?memDC.CreateCompatibleDC(NULL);
?//建立與屏幕顯示兼容的內存顯示設備
?MemBitmap.CreateCompatibleBitmap(pDC,rect.Width(),rect.Height());
?//選取空白位圖
?memDC.SelectObject(MemBitmap);
?memDC.FillSolidRect(100,0,rect.Width(),rect.Height(),RGB(255,0,0));
?EasyGraphics* graph=NULL;
?for(INT_PTR i=0;i<m_GraphAry.GetCount();i++)
?{
??graph=(EasyGraphics*)m_GraphAry[i];
??DrawGraphics(&memDC,graph);
?}
?pDC->BitBlt(0,0,rect.Width(),rect.Height(),&memDC,0,0,SRCCOPY);
}