如何有效地使用对话框

译者：徐景周(原作：VGirish)

Q:如何在对话框中加入工具条

在 OnInitDialog 中加入下面代码：

BOOL CYourDlg::OnInitDialog(){       CDialog::OnInitDialog();       // Create the toolbar. To understand the meaning of the styles used, you        // can take a look at the MSDN for the Create function of the CToolBar class.          ToolBar.Create(this, WS_CHILD | WS_VISIBLE | CBRS_TOP | CBRS_TOOLTIPS |CBRS_FLYBY | CBRS_BORDER_BOTTOM);      // I have assumed that you have named your toolbar''s resource as IDR_TOOLBAR1.      // If you have given it a different name, change the line below to accomodate       // that by changing the parameter for the LoadToolBar function.        ToolBar.LoadToolBar(IDR_TOOLBAR1);        CRect rcClientStart;      CRect rcClientNow;      GetClientRect(rcClientStart);      // To reposition and resize the control bar     RepositionBars(AFX_IDW_CONTROLBAR_FIRST, AFX_IDW_CONTROLBAR_LAST,0, reposQuery, rcClientNow);     CPoint ptOffset(rcClientNow.left - rcClientStart.left,rcClientNow.top-rcClientStart.top);     CRect rcChild;     CWnd* pwndChild = GetWindow(GW_CHILD);     while (pwndChild)     {       pwndChild->GetWindowRect(rcChild);       ScreenToClient(rcChild);       rcChild.OffsetRect(ptOffset);       pwndChild->MoveWindow(rcChild, FALSE);       pwndChild = pwndChild->GetNextWindow();     }   CRect rcWindow;     GetWindowRect(rcWindow);     rcWindow.right += rcClientStart.Width() - rcClientNow.Width();     rcWindow.bottom += rcClientStart.Height() - rcClientNow.Height();     MoveWindow(rcWindow, FALSE);     // And position the control bars     RepositionBars(AFX_IDW_CONTROLBAR_FIRST, AFX_IDW_CONTROLBAR_LAST, 0);       return TRUE;  // return TRUE  unless you set the focus to a control  }

Q:如何改变对话框的形状？

可用下面一些函数：
CreatePolygonRgn
CreateRectRgn
CreateRoundRectRgn 等.

  CRgn m_rgn;  // Put this in your dialog''s header file. i.e. a member variable  // This Gets the size of the Dialog: This piece of code is to be placed in the  // OnInitDialog Function of your dialog.  CRect rcDialog  GetClientRect(rcDialog);  // The following code Creates the area and assigns it to your Dialog  m_rgn.CreateEllipticRgn(0, 0, rcDialog.Width(), rcDialogHeight());  SetWindowRgn(GetSafeHwnd(), (HRGN) m_rgn, TRUE);

Q：如何实现非客户区移动？

可用下面二种方法

// Handler for WM_LBUTTONDOWN message  void CYourDialog::OnLButtonDown(UINT nFlags, CPoint point)  {     CDialog::OnLButtonDown(nFlags, point);     PostMessage( WM_NCLBUTTONDOWN, HTCAPTION, MAKELPARAM( point.x, point.y));  }  // Handler for WM_NCHITTEST message  LONG CYourDialog::OnNcHitTest( UINT uParam, LONG lParam )  {       int xPos = LOWORD(lParam);     int yPos = HIWORD(lParam);     UINT nHitTest = CDialog::OnNcHitTest(CSize(xPos, yPos));     return (nHitTest == HTCLIENT) ? HTCAPTION : nHitTest;  }

Q:如何使对话框初始为最小化状态？

在 OnInitDialog 中加入下面代码：

SendMessage(WM_SYSCOMMAND, SC_MAXIMIZE, NULL);

Q:如何限定对话框大小范围？

在 WM_SIZING中加入下面代码：

void CYourDialog::OnSizing(UINT fwSide, LPRECT pRect)   {     if(pRect->right - pRect->left <=200)     pRect->right = pRect->left + 200;     if(pRect->bottom - pRect->top <=200)     pRect->bottom = pRect->top + 200;     CDialog::OnSizing(fwSide, pRect);  }

Q:如何在对话框中加入状态条？

定义 CStatusBar 变量：

CStatusBar m_StatusBar;

定义状态条指定状态：

static UINT BASED_CODE indicators[] =  {     ID_INDICATOR_CAPS,     ID_INDICATOR_NUM  };

在 OnInitDialog 中加入下面代码：

  m_StatusBar.CreateEx(this,SBT_TOOLTIPS,WS_CHILD|WS_VISIBLE|CBRS_BOTTOM,AFX_IDW_STATUS_BAR);   // Set the indicators namely caps and nums lock status  m_StatusBar.SetIndicators(indicators,sizeof(indicators)/sizeof(UINT));  CRect rect;  GetClientRect(&rect);  m_StatusBar.SetPaneInfo(0,ID_INDICATOR_CAPS,SBPS_NORMAL,rect.Width()/2);  m_StatusBar.SetPaneInfo(1,ID_INDICATOR_NUM,SBPS_STRETCH ,rect.Width()/2);  RepositionBars(AFX_IDW_CONTROLBAR_FIRST,AFX_IDW_CONTROLBAR_LAST,ID_INDICATOR_NUM);  m_StatusBar.GetStatusBarCtrl().SetBkColor(RGB(180,180,180));

如何有效的使用对话框之二
译者：徐景周(原作：Nishant S )

本文是《如何有效使用对话框》一文的继续.

1. 如何有效地使初始窗口不显示
当我们想让窗口初始时不显示时，通常会用ShowWindow(SW_HIDE) ,但实际上还是在启动是可以看到窗口一闪而过的痕迹。所以，可以使用下面的方法来实现它：
(1.1)先在构造函数中设置布乐变量 visible值为false.

visible = false;

(1.2)重载 WM_WINDOWPOSCHANGING，并添加下面代码：

void CTest_deleteDlg::OnWindowPosChanging(WINDOWPOS FAR* lpwndpos) {    if(!visible)        lpwndpos->flags &= ~SWP_SHOWWINDOW;    CDialog::OnWindowPosChanging(lpwndpos);}

(1.3)然后设布尔visible变量值为true，并在要显示窗口时，再用ShowWindow(SW_SHOW)既可。

visible = true;ShowWindow(SW_SHOW);

2. 对话框的全屏显示
对话框的全屏显示可以在OnInitDialog()中用 SetWindowPos 和 HWND_TOPMOST 来实现对话框的重新大小。

BOOL CFullScrDlgDlg::OnInitDialog(){    CDialog::OnInitDialog();    //...    int cx, cy;     HDC dc = ::GetDC(NULL);     cx = GetDeviceCaps(dc,HORZRES) +         GetSystemMetrics(SM_CXBORDER);     cy = GetDeviceCaps(dc,VERTRES) +        GetSystemMetrics(SM_CYBORDER);     ::ReleaseDC(0,dc);     //去除标题和边框    SetWindowLong(m_hWnd, GWL_STYLE,         GetWindowLong(m_hWnd, GWL_STYLE) &     (~(WS_CAPTION | WS_BORDER)));     // 置对话框为最顶端并扩充到整个屏幕    ::SetWindowPos(m_hWnd, HWND_TOPMOST,         -(GetSystemMetrics(SM_CXBORDER)+1),         -(GetSystemMetrics(SM_CYBORDER)+1),         cx+1,cy+1, SWP_NOZORDER);     //...    return TRUE; }

3. 如何在2K/xp下使窗口获取焦点
在2K/XP下我们可以用 AttachThreadInput 和SetForegroundWindow来有效的获取焦点。

//捕捉并设置当前焦点窗口为我们的窗口AttachThreadInput(    GetWindowThreadProcessId(        ::GetForegroundWindow(),NULL),    GetCurrentThreadId(),TRUE);//置我们的为焦点窗口SetForegroundWindow();SetFocus(); //释放threadAttachThreadInput(    GetWindowThreadProcessId(        ::GetForegroundWindow(),NULL),    GetCurrentThreadId(),FALSE);

4. 使你的对话框位于最顶端
可以直接在 OnInitDialog()中用SetWindowPos来实现。

SetWindowPos(&this->wndTopMost,0,0,0,0,SWP_NOMOVE|SWP_NOSIZE);

5. 如何动态放大/缩小对话框
还是可以用SetWindowPos或MoveWindow来实现它。

void CTest_deleteDlg::OnMakeSmall() {    SetWindowPos(NULL,0,0,200,200,SWP_NOZORDER|SWP_NOMOVE);}void CTest_deleteDlg::OnExpand() {    SetWindowPos(NULL,0,0,500,300,SWP_NOZORDER|SWP_NOMOVE);}

或:

//伸、缩在IDC_DYCREDITS和IDC_COPYRIGHT两STATIC控件间，做为分隔线BOOL CAbout::OnInitDialog() {CDialog::OnInitDialog();//"关于"对话框中对话框可收缩效果CRect Rect1,Rect2;      //对话框收缩时大小GetDlgItem(IDC_DYCREDITS)->GetWindowRect(Rect1); GetDlgItem(IDC_COPYRIGHT)->GetWindowRect(Rect2); m_nReducedHeight = Rect1.Height()+(Rect1.top -Rect2.bottom)/2; //收缩后窗体高度dlgRect.bottom -= (Rect1.Height()+(Rect1.top -Rect2.bottom)/2); MoveWindow(&dlgRect);              //如果要显示对话框起始动态效果的话，不能使用该句m_bVertical=false;                                //默认收缩对话框}// ---------------------------------------------------------//名称: OnMore//功能: 是否允许显示//变量: 无//返回: 无//编写: 徐景周，2002.4.8// ---------------------------------------------------------void CAbout::OnMore() {m_bVertical = !m_bVertical; if(m_bVertical == FALSE)//不显示{ SetDlgItemText(ID_MORE,_T("更多>>"));SizeWindow(m_nReducedHeight,true);//m_DyCredits.EndScrolling();              //停止滚动} else//显示{ SetDlgItemText(ID_MORE,_T("<<隐藏"));SizeWindow(m_nReducedHeight,false);m_DyCredits.StartScrolling();//开始滚动} UpdateWindow(); }// ---------------------------------------------------------//名称: SizeWindow//功能: 伸展或收缩对话框    //变量: ReduceHeight-收缩高度，bExtend-是否伸展//返回: 无//编写: 徐景周，2002.4.8// ---------------------------------------------------------void CAbout::SizeWindow(int ReduceHeight, bool bExtend){CRect rc;GetWindowRect(&rc);if(bExtend){for (int i= 0; i < ReduceHeight; i++){rc.bottom--;MoveWindow(&rc);}}else{for (int i= 0; i < ReduceHeight; i++){rc.bottom++;MoveWindow(&rc);}}}

6. 如何让对话框回到屏幕中来
当对话框被拖离屏幕时，可用下面代码使其回到屏幕中。

SendMessage(DM_REPOSITION);

注：它必须是顶端窗口且不是child窗口。

7. 如何给对话框添加或去掉最大/最小化按钮
在OnCreate()或OnInitDialog() 改变其显示风格既可。

int CTest_deleteDlg::OnCreate(LPCREATESTRUCT lpCreateStruct) {    if (CDialog::OnCreate(lpCreateStruct) == -1)        return -1;    // TODO: Add your specialized creation code here    SetWindowLong(this->m_hWnd,GWL_STYLE,        GetWindowLong(this->m_hWnd,GWL_STYLE) |             WS_MINIMIZEBOX | WS_MAXIMIZEBOX);    return 0;}

或用：

ModifyStyle (NULL, WS_MAXIMIZEBOX);

8. 改变鼠标指针
可以在OnSetCursor中实现.

BOOL CTest_deleteDlg::OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message) {    // TODO: Add your message handler code here and/or call default    SetCursor(AfxGetApp()->LoadStandardCursor(IDC_UPARROW));    // Now we return instead of calling the base class    return 0;    // return CDialog::OnSetCursor(pWnd, nHitTest, message);}

9. 改变对话框的前景和背景色
可以在InitInstance()中实现。

//红色背景、绿色前景SetDialogBkColor(RGB(255,0,0),RGB(0,255,0)); 

10. 在任务条上不显示图标
先从CWinApp继承类中建立一个不显示的顶级窗口.

CFrameWnd *abc=new CFrameWnd();abc->Create(0,0,WS_OVERLAPPEDWINDOW);CNoTaskBarIconDlg dlg(abc);m_pMainWnd = &dlg;int nResponse = dlg.DoModal();if (nResponse == IDOK){}else if (nResponse == IDCANCEL){}delete abc;

在 OnInitDialog中修改显示风格 WS_EX_APPWINDOW.

BOOL CNoTaskBarIconDlg::OnInitDialog(){    CDialog::OnInitDialog();    ModifyStyleEx(WS_EX_APPWINDOW,0);    SetIcon(m_hIcon, TRUE);  // Set big icon    SetIcon(m_hIcon, FALSE); // Set small icon    // TODO: Add extra initialization here    return TRUE;  // return TRUE  unless you set the focus to a control}

11. 加入上、下文帮助
在 OnInitDialog 修改显示风格，加入上、下文HLP帮助显示.

BOOL HelpDialog::OnInitDialog() {    ModifyStyleEx(0, WS_EX_CONTEXTHELP);    return CDialog::OnInitDialog();}

重载OnHelpInfo(...)，用显示相关帮助信息

BOOL HelpDialog::OnHelpInfo(HELPINFO* pHelpInfo) {    short state = GetKeyState (VK_F1);    if (state < 0)   // F1 key is down, get help for the dialog        return CDialog::OnHelpInfo(pHelpInfo);    else    {    // F1 key not down, get help for specific control        if (pHelpInfo->dwContextId)            WinHelp (pHelpInfo->dwContextId,                 HELP_CONTEXTPOPUP);        return TRUE;    }}