CMainWindow

Microsoft Windows 操作系统将以下用户操作转换为标准窗口消息，并将其发送到 StoClien 应用程序中的main过程：

• 用户单击鼠标左键或平板电脑设备中的笔尖开关以启动线条绘制序列。
• 用户单击并按住按钮并移动鼠标以绘制线条。
• 释放鼠标左键时，序列结束。

下面的示例代码演示了此过程。

CMainWindow：：WindowProc (STOCLIEN。CPP)

LRESULT CMainWindow::WindowProc(
            UINT uMsg,
            WPARAM wParam,
            LPARAM lParam)
  {
    LRESULT lResult = FALSE;

    switch (uMsg)
    {
      case WM_CREATE:
        break;

      case WM_ACTIVATE:
        // A mouse click reactivates the paint procedure.
        // This is used to paint a new window when a user
        // selects a portion of the STOCLIEN window that is 
        // visible beneath another window. This message is  
        // sent in the WindowProc handle.
        if (WA_CLICKACTIVE == LOWORD(wParam))
          m_pGuiPaper->PaintWin();
        lResult = ::DefWindowProc(m_hWnd, uMsg, wParam, lParam);
        break;

      case WM_SIZE:
        // Handle a resize of this window.
        m_wWidth = LOWORD(lParam);
        m_wHeight = HIWORD(lParam);
        // Inform CGuiPaper of the change.
        m_pGuiPaper->Resize(m_wWidth, m_wHeight);
        break;

      case WM_PAINT:
        // This is a message to repaint the window.
        {
          PAINTSTRUCT ps;

          if(BeginPaint(m_hWnd, &ps))
            EndPaint(m_hWnd, &ps);

          m_pGuiPaper->PaintWin();
        }
        break;

      case WM_LBUTTONDOWN:
        // Start sequence of ink drawing to the paper.
        m_pGuiPaper->InkStart(LOWORD(lParam), HIWORD(lParam));
        break;

      case WM_MOUSEMOVE:
        // Draw inking sequence data.
        m_pGuiPaper->InkDraw(LOWORD(lParam), HIWORD(lParam));
        break;

      case WM_LBUTTONUP:
        // Stop an ink drawing sequence.
        m_pGuiPaper->InkStop(LOWORD(lParam), HIWORD(lParam));
        break;

      case WM_COMMAND:
        // Dispatch and handle any Menu command messages received.
        lResult = DoMenu(wParam, lParam);
        break;

      case WM_CHAR:
        if (wParam == 0x1b)
        {
          // Exit this application if user presses the ESC key.
          ::PostMessage(m_hWnd, WM_CLOSE, 0, 0);
        }
        break;

      case WM_CLOSE:
        // The user selected Close on the main window System menu
        // or Exit on the File menu.
        // If there is unsaved ink data, then prompt
        // the user. If the user cancels, do not close the window.
        if (IDCANCEL == m_pGuiPaper->AskSave())
          break;
      case WM_QUIT:
        // When exiting the application, close any associated help
        // windows.
        // ::WinHelp(m_hWnd, m_szHelpFile, HELP_QUIT, 0);
      default:
        // If there are any messages that have not been handled,
        // send them to the default window procedure.
        lResult = ::DefWindowProc(m_hWnd, uMsg, wParam, lParam);
        break;
    }

    return(lResult);
  }

当WM_LBUTTONDOWN消息传送鼠标位置数据时，开始绘制线条序列。

CMainWindow 具有指向 CGuiPaper 对象的指针，并调用 CGuiPaper：：InkStart 方法来启动线条绘制序列。

移动鼠标进行绘制时，会将包含鼠标位置数据的单独 WM_MOUSEMOVE 消息序列提供给 CGuiPaper：：InkDraw 方法。

松开鼠标左键时，会收到 WM_LBUTTONUP 消息。 CGuiPaper：：InkStop 方法停止线条绘制序列。