 圖一、實(shí)現(xiàn)圖形超鏈接功能的程序界面圖 |
一、 實(shí)現(xiàn)方法
著名的CHyperLink類只能提供文字鏈接，不能用于圖形控件的超鏈接，于是本實(shí)例在其基礎(chǔ)上修改了一下，定義了一個CMapHyperLink類，該類現(xiàn)在只對圖形控件(picture control)生效。用戶可使用成員函數(shù)void SetURL(CString strURL)設(shè)置要訪問的互聯(lián)網(wǎng)地址，如SetURL("http://www.google.com")；使用成員函數(shù)void SetTipText(CString strURL)設(shè)置超鏈接提示條(CToolTipCtrl)的文字內(nèi)容，如果不在此設(shè)置，那就默認(rèn)是您設(shè)置的URL地址，如SetTipText("歡迎訪問強(qiáng)大的google搜索")；使用成員函數(shù)void SetLinkCursor(HCURSOR hCursor)設(shè)置鼠標(biāo)在超鏈接狀態(tài)的圖標(biāo)，默認(rèn)是手型圖標(biāo)。該類還提供了HCURSOR GetLinkCursor() const、void SetAutoSize(BOOL bAutoSize = TRUE)等成員函數(shù)，提供了一些相應(yīng)的輔助功能，讀者朋友可以參考代碼部分。這里主要講述三個主要的問題：一是如何實(shí)現(xiàn)提示功能；二是在控件上如何改變鼠標(biāo)的形狀，給用戶提供另外一種暗示-當(dāng)前區(qū)域提供超鏈接功能；三是如何根據(jù)網(wǎng)頁或信箱地址啟動超鏈接功能。
Visual C++提供了CCtoolTipCtrl類用來實(shí)現(xiàn)提示功能。工具提示控制是一個小窗口，在其中顯示單行文字用以描述應(yīng)用程序中的工具的用途。這里的工具所指的既可以是窗口（如工具欄上的按鈕），也可以是一個固定的區(qū)域。大家都知道利用APPWIZARD生成 的應(yīng)用程序中工具欄帶有提示，當(dāng)你將鼠標(biāo)放在工具欄某一個按鈕上時，將顯示一個小提示框告訴你按鈕的功能，這種功能方便了軟件的使用者。但是在超鏈接區(qū)如何實(shí)現(xiàn)提示呢？首先聲明一個CtoolTipCtrl類的變量，調(diào)用Create（）成員函數(shù)創(chuàng)建通用工具提示，并將它附在CtoolTipCtrl對象上，然后調(diào)用CtoolTipCtrl類的AddToo（）成員函數(shù)注冊工具提示控制，從而為光標(biāo)放在規(guī)定的窗口或區(qū)域內(nèi)時顯示工具提示做準(zhǔn)備。該函數(shù)的原形為：
| BOOL AddTool( CWnd* pWnd，LPCTSTR lpszText， LPCRECT lpRectTool,UINT nIDTOOL ); |
其中參數(shù)pWnd為指向包含工具提示控制的窗口指針，參數(shù)lpszText為所要在工具提示中顯示的文字，參數(shù)lpRectTool為工具書提示所對應(yīng)的窗口或規(guī)定區(qū)域，參數(shù)nIDTOOL為工具提示的標(biāo)志號。
在調(diào)用CtoolTipCtrl類的Active（）函數(shù)激活提示后，最后要作的工作是調(diào)用CtoolTipCtrl類的RelayEvent（）函數(shù)將鼠標(biāo)的WM_LBUTTONDOWN、WM_MOUSEMOVE、WM_LBUTTONUP等消息傳遞給工具提示控制對象，以便控件進(jìn)行提示處理。
下面的代碼實(shí)現(xiàn)了在應(yīng)用程序的視圖區(qū)顯示對應(yīng)點(diǎn)的坐標(biāo)為例：
| //在文件頭定義的全局變量 CToolTipCtrl m_ToolTip;//工具提示對象 char string[50];//用來存放提示文字 CRect rect;//用來存放工具提示所對應(yīng)的窗口的尺寸 #define IDC_CONST 12345//定義的工具提示標(biāo)志號，注意不要和系統(tǒng)沖突 void CTestView::OnMouseMove(UINT nFlags, CPoint point) { // TODO: Add your message handler code here and/or call default wsprintf(string,"%d,%d",point.x,point.y); GetClientRect(&recty); m_ToolTip.AddTool(this,string,&rect,IDC_CONST); m_ToolTip.Activate(TRUE); CView::OnMouseMove(nFlags, point); } LRESULT CTestView::WindowProc(UINT message, WPARAM wParam, LPARAM lParam) { // TODO: Add your specialized code here and/or call the base class switch(message) {case WM_LBUTTONDOWN: case WM_RBUTTONDOWN: case WM_MBUTTONDOWN: case WM_LBUTTONUP: case WM_MBUTTONUP: case WM_RBUTTONUP: case WM_MOUSEMOVE: {MSG msg; msg.hwnd=m_hWnd; msg.message=message; msg.wParam=wParam; msg.lParam=lParam; m_ToolTip.RelayEvent(&msg); } } return CView::WindowProc(message, wParam, lParam); } |
如果用戶想動態(tài)的改變提示字符串，可以調(diào)用CtoolTipCtrl類的成員函數(shù)UpdateTipText（）來實(shí)現(xiàn)，該函數(shù)的原型為：
| void UpdateTipText( LPCTSTR lpszText, CWnd* pWnd, UINT nIDTool = 0 ); |
該函數(shù)的參數(shù)的含義與成員函數(shù)AddTool（）的參數(shù)的含義大同小異，這里不再贅述。
對于超鏈接來說，一般會在超鏈接區(qū)域改變鼠標(biāo)的形狀，顯示手狀的鼠標(biāo)，提示這是一個超鏈接區(qū)域。當(dāng)然可以在程序中添加一個手狀的光標(biāo)資源，然后使用LoadCursor（）函數(shù)等加載，這種方法對廣大讀者朋友一定是耳熟能詳了，所以為了擴(kuò)大讀者朋友的編程思路，這里介紹一種從Windows的winhlp32.exe文件中加載光標(biāo)資源，代碼如下：
| void CMapHyperLink::SetDefaultCursor() { if (m_hLinkCursor == NULL) // No cursor handle - load our own { // Get the windows directory CString strWndDir; GetWindowsDirectory(strWndDir.GetBuffer(MAX_PATH), MAX_PATH); strWndDir.ReleaseBuffer(); strWndDir += _T("\winhlp32.exe"); // This retrieves cursor #106 from winhlp32.exe, which is a hand pointer HMODULE hModule = LoadLibrary(strWndDir); if (hModule) { HCURSOR hHandCursor = ::LoadCursor(hModule, MAKEINTRESOURCE(106)); if (hHandCursor) m_hLinkCursor = CopyCursor(hHandCursor); } FreeLibrary(hModule); } } |
為了根據(jù)網(wǎng)頁或信箱地址實(shí)現(xiàn)超鏈接功能，需要用到一個WINDOWS API函數(shù)ShellExecute（），其原型為：
| HINSTANCE ShellExecute( HWND hwnd, //窗口句柄 LPCTSTR lpOperation, //操作類型 LPCTSTR lpFile, //文件指針 LPCTSTR lpParameters, //文件可帶的參數(shù) LPCTSTR lpDirectory, //缺省目錄 INT nShowCmd //顯示方式 ); |
ShellExecute（）函數(shù)用于打開或執(zhí)行一個文件，在調(diào)用此函數(shù)時只須指定要打開或執(zhí)行的文件名，而不必管用什么程序去打開或執(zhí)行文件，WINDOWS會自動根據(jù)要打開或執(zhí)行的文件去判斷該如何執(zhí)行文件或用什么程序去打開文件。函數(shù)中的參數(shù)lpOperation說明所要執(zhí)行的操作，該值可以設(shè)置為"Open"、"Print"、"Explore"，分別用來進(jìn)行"打開"、"打印"、"瀏覽"操作。下面給出了ShellExecute（）函數(shù)的一些使用方法：
�。�1）打開一個應(yīng)用程序：
| ShellExecute(this->m_hWnd,"open","calc.exe","","", SW_SHOW ); 或 ShellExecute(this->m_hWnd,"open","notepad.exe", "c:\MyLog.log","",SW_SHOW ); |
�。�2）打開一個同系統(tǒng)程序相關(guān)連的文檔
| ShellExecute(this->m_hWnd,"open", "c:\abc.txt","","",SW_SHOW ); |
�。�3）打開一個網(wǎng)頁
| ShellExecute(this->m_hWnd,"open", " http://www.google.com","","",/ SW_SHOW ); |
（4）激活相關(guān)程序，發(fā)送EMAIL
| ShellExecute(this->m_hWnd,"open","mailto:nishinapp@yahoo.com","","", W_SHOW ); |
�。�5）用系統(tǒng)打印機(jī)打印文檔
| ShellExecute(this->m_hWnd,"print", "c:\abc.txt","","", SW_HIDE); |
（6）用系統(tǒng)查找功能來查找指定文件
| ShellExecute(m_hWnd,"find","d:\nish", NULL,NULL,SW_SHOW); |
�。�7）啟動一個程序，直到它運(yùn)行結(jié)束
| SHELLEXECUTEINFO ShExecInfo = {0}; ShExecInfo.cbSize = sizeof(SHELLEXECUTEINFO); ShExecInfo.fMask = SEE_MASK_NOCLOSEPROCESS; ShExecInfo.hwnd = NULL; ShExecInfo.lpVerb = NULL; ShExecInfo.lpFile = "c:\MyProgram.exe"; ShExecInfo.lpParameters = ""; ShExecInfo.lpDirectory = NULL; ShExecInfo.nShow = SW_SHOW; ShExecInfo.hInstApp = NULL; ShellExecuteEx(&ShExecInfo); WaitForSingleObject(ShExecInfo.hProcess,INFINITE); 或： PROCESS_INFORMATION ProcessInfo; STARTUPINFO StartupInfo; //This is an [in] parameter ZeroMemory(&StartupInfo, sizeof(StartupInfo)); StartupInfo.cb = sizeof StartupInfo ; //Only compulsory field if(CreateProcess("c:\winnt\notepad.exe", NULL, NULL,NULL,FALSE,0,NULL, NULL,&StartupInfo,&ProcessInfo)) { WaitForSingleObject(ProcessInfo.hProcess,INFINITE); CloseHandle(ProcessInfo.hThread); CloseHandle(ProcessInfo.hProcess); } else { MessageBox("The process could not be started..."); } |
�。�8）顯示文件或文件夾的屬性
| SHELLEXECUTEINFO ShExecInfo ={0}; ShExecInfo.cbSize = sizeof(SHELLEXECUTEINFO); ShExecInfo.fMask = SEE_MASK_INVOKEIDLIST ; ShExecInfo.hwnd = NULL; ShExecInfo.lpVerb = "properties"; ShExecInfo.lpFile = "c:"; //can be a file as well ShExecInfo.lpParameters = ""; ShExecInfo.lpDirectory = NULL; ShExecInfo.nShow = SW_SHOW; ShExecInfo.hInstApp = NULL; ShellExecuteEx(&ShExecInfo); |
Windows還提供了一個與ShellExecuteEx（）函數(shù)相類似的函數(shù)WinExec（），它相對于ShellExecuteEx（）來說更簡單易用，只是功能沒有它強(qiáng)大而已，具體使用方法讀者朋友自行參閱MSDN。
二、編程步驟
l、啟動Visual C++6.0，生成一個基于對話框的應(yīng)用程序，將該程序命名為"Test"；
2、在對話框上放置一個靜態(tài)控件，并顯示一幅圖象；
3、使用Class Wizard為應(yīng)用程序添加一個CMapHyperLink類，其基類為CStatic；
4、在對話框中添加一個CmapHyperLink類對象m_MapHyperLink1；
5、添加代碼，編譯運(yùn)行程序。
三、程序代碼
| ///////////////////////////////////////////////////////////////////////// //MapHyperLink.h , MapHyperLink.cpp #if !defined(AFX_HYPERLINK_H__D1625061_574B_11D1_ABBA_00A0243D1382__INCLUDED_) #define AFX_HYPERLINK_H__D1625061_574B_11D1_ABBA_00A0243D1382__INCLUDED_ #if _MSC_VER >= 1000 #pragma once #endif // _MSC_VER >= 1000 // CHyperLink window class CMapHyperLink : public CStatic { // Construction/destruction public: CMapHyperLink(); virtual ~CMapHyperLink(); public: void SetURL(CString strURL); CString GetURL() const; void SetTipText(CString strURL); CString GetTipText() const; void SetVisited(BOOL bVisited = TRUE); BOOL GetVisited() const; void SetLinkCursor(HCURSOR hCursor); HCURSOR GetLinkCursor() const; void SetAutoSize(BOOL bAutoSize = TRUE); BOOL GetAutoSize() const; // Overrides // ClassWizard generated virtual function overrides //{{AFX_VIRTUAL(CHyperLink) public: virtual BOOL PreTranslateMessage(MSG* pMsg); protected: virtual void PreSubclassWindow(); //}}AFX_VIRTUAL // Implementation protected: HINSTANCE GotoURL(LPCTSTR url, int showcmd); void ReportError(int nError); LONG GetRegKey(HKEY key, LPCTSTR subkey, LPTSTR retdata); void PositionWindow(); void SetDefaultCursor(); // Protected attributes protected: BOOL m_bOverControl; // cursor over control? BOOL m_bVisited; // Has it been visited? BOOL m_bAdjustToFit; // Adjust window size to fit text? CString m_strURL; // hyperlink URL CString m_strTipText; // TipTool control' text HCURSOR m_hLinkCursor; // Cursor for hyperlink CToolTipCtrl m_ToolTip; // The tooltip protected: // Generated message map functions //{{AFX_MSG(CHyperLink) afx_msg BOOL OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message); afx_msg void OnMouseMove(UINT nFlags, CPoint point); //}}AFX_MSG afx_msg void OnClicked(); DECLARE_MESSAGE_MAP() }; #endif ///////////////////////////////////////////////////////////// MapHyperLink.cpp #include "stdafx.h" #include "MapHyperLink.h" #ifdef _DEBUG #define new DEBUG_NEW #undef THIS_FILE static char THIS_FILE[] = __FILE__; #endif #define TOOLTIP_ID 1 CMapHyperLink::CMapHyperLink() { m_hLinkCursor = NULL; // No cursor as yet m_bOverControl = FALSE; // Cursor not yet over control m_bVisited = FALSE; // Hasn't been visited yet. m_bAdjustToFit = TRUE; // Resize the window to fit the text? m_strURL.Empty(); m_strTipText.Empty(); } CMapHyperLink::~CMapHyperLink() {} BEGIN_MESSAGE_MAP(CMapHyperLink, CStatic) //{{AFX_MSG_MAP(CMapHyperLink) ON_CONTROL_REFLECT(STN_CLICKED, OnClicked) ON_WM_SETCURSOR() ON_WM_MOUSEMOVE() //}}AFX_MSG_MAP END_MESSAGE_MAP() // CMapHyperLink message handlers BOOL CMapHyperLink::PreTranslateMessage(MSG* pMsg) { m_ToolTip.RelayEvent(pMsg); return CStatic::PreTranslateMessage(pMsg); } void CMapHyperLink::OnClicked() { int result = (int)GotoURL(m_strURL, SW_SHOW); m_bVisited = (result > HINSTANCE_ERROR); if (!m_bVisited) { MessageBeep(MB_ICONEXCLAMATION); // Unable to follow link ReportError(result); } else SetVisited(); // Repaint to show visited colour } void CMapHyperLink::OnMouseMove(UINT nFlags, CPoint point) { CStatic::OnMouseMove(nFlags, point); if (m_bOverControl) // Cursor is currently over control { CRect rect; GetClientRect(rect); if (!rect.PtInRect(point)) { m_bOverControl = FALSE; ReleaseCapture(); RedrawWindow(); return; } } else // Cursor has just moved over control { m_bOverControl = TRUE; RedrawWindow(); SetCapture(); } } BOOL CMapHyperLink::OnSetCursor(CWnd* /*pWnd*/, UINT /*nHitTest*/, UINT /*message*/) { if (m_hLinkCursor) { ::SetCursor(m_hLinkCursor); return TRUE; } return FALSE; } void CMapHyperLink::PreSubclassWindow() { // We want to get mouse clicks via STN_CLICKED DWORD dwStyle = GetStyle(); ::SetWindowLong(GetSafeHwnd(), GWL_STYLE, dwStyle | SS_NOTIFY); SetDefaultCursor(); // Try and load up a "hand" cursor // Create the tooltip CRect rect; GetClientRect(rect); m_ToolTip.Create(this); if (m_strTipText.IsEmpty()) { m_strTipText = m_strURL; } m_ToolTip.AddTool(this, m_strTipText, rect, TOOLTIP_ID); CStatic::PreSubclassWindow(); } ////////////////////////////////////////////// CMapHyperLink operations void CMapHyperLink::SetURL(CString strURL) { m_strURL = strURL; if (::IsWindow(GetSafeHwnd())) { PositionWindow(); if (m_strTipText.IsEmpty()) { m_strTipText = strURL; } m_ToolTip.UpdateTipText(m_strTipText, this, TOOLTIP_ID); } } CString CMapHyperLink::GetURL() const { return m_strURL; } void CMapHyperLink::SetTipText(CString strTipText) { m_strTipText = strTipText; if (::IsWindow(GetSafeHwnd())) { PositionWindow(); m_ToolTip.UpdateTipText(m_strTipText, this, TOOLTIP_ID); } } CString CMapHyperLink::GetTipText() const { return m_strTipText; } void CMapHyperLink::SetVisited(BOOL bVisited /* = TRUE */) { m_bVisited = bVisited; if (::IsWindow(GetSafeHwnd())) Invalidate(); } BOOL CMapHyperLink::GetVisited() const { return m_bVisited; } void CMapHyperLink::SetLinkCursor(HCURSOR hCursor) { m_hLinkCursor = hCursor; if (m_hLinkCursor == NULL) SetDefaultCursor(); } HCURSOR CMapHyperLink::GetLinkCursor() const { return m_hLinkCursor; } void CMapHyperLink::SetAutoSize(BOOL bAutoSize /* = TRUE */) { m_bAdjustToFit = bAutoSize; if (::IsWindow(GetSafeHwnd())) PositionWindow(); } BOOL CMapHyperLink::GetAutoSize() const { return m_bAdjustToFit; } // Move and resize the window so that the window is the same size void CMapHyperLink::PositionWindow() { if (!::IsWindow(GetSafeHwnd()) || !m_bAdjustToFit) return; // Get the current window position CRect rect; GetWindowRect(rect); CWnd* pParent = GetParent(); if (pParent) pParent->ScreenToClient(rect); CRect rectMap; GetClientRect(rectMap); // Get the text justification via the window style DWORD dwStyle = GetStyle(); // Recalc the window size and position based on the text justification if (dwStyle & SS_CENTERIMAGE) rect.DeflateRect(0, (rect.Height() - rectMap.Height())/2); else rect.bottom = rect.top + rectMap.Height(); if (dwStyle & SS_CENTER) rect.DeflateRect((rect.Width() - rectMap.Width())/2, 0); else if (dwStyle & SS_RIGHT) rect.left = rect.right - rectMap.Width(); else // SS_LEFT = 0, so we can't test for it explicitly rect.right = rect.left + rectMap.Width(); // Move the window SetWindowPos(NULL, rect.left, rect.top, rect.Width(), rect.Height(), SWP_NOZORDER); } /////////////////////////////////////////////////// CMapHyperLink implementation void CMapHyperLink::SetDefaultCursor() { if (m_hLinkCursor == NULL) // No cursor handle - load our own { // Get the windows directory CString strWndDir; GetWindowsDirectory(strWndDir.GetBuffer(MAX_PATH), MAX_PATH); strWndDir.ReleaseBuffer(); strWndDir += _T("\winhlp32.exe"); // This retrieves cursor #106 from winhlp32.exe, which is a hand pointer HMODULE hModule = LoadLibrary(strWndDir); if (hModule) { HCURSOR hHandCursor = ::LoadCursor(hModule, MAKEINTRESOURCE(106)); if (hHandCursor) m_hLinkCursor = CopyCursor(hHandCursor); } FreeLibrary(hModule); } } LONG CMapHyperLink::GetRegKey(HKEY key, LPCTSTR subkey, LPTSTR retdata) { HKEY hkey; LONG retval = RegOpenKeyEx(key, subkey, 0, KEY_QUERY_VALUE, &hkey); if (retval == ERROR_SUCCESS) { long datasize = MAX_PATH; TCHAR data[MAX_PATH]; RegQueryValue(hkey, NULL, data, &datasize); lstrcpy(retdata,data); RegCloseKey(hkey); } return retval; } void CMapHyperLink::ReportError(int nError) { CString str; switch (nError) { case 0: str = "The operating system is out\nof memory or resources."; break; case SE_ERR_PNF: str = "The specified path was not found."; break; case SE_ERR_FNF: str = "The specified file was not found."; break; case ERROR_BAD_FORMAT: str = "The .EXE file is invalid\n(non-Win32 .EXE or error in .EXE image)."; break; case SE_ERR_ACCESSDENIED: str = "The operating system denied\naccess to the specified file."; break; case SE_ERR_ASSOCINCOMPLETE: str = "The filename association is\nincomplete or invalid."; break; case SE_ERR_DDEBUSY: str = "The DDE transaction could not\nbe completed because other DDE transactions\nwere being processed."; break; case SE_ERR_DDEFAIL: str = "The DDE transaction failed."; break; case SE_ERR_DDETIMEOUT: str = "The DDE transaction could not\nbe completed because the request timed out."; break; case SE_ERR_DLLNOTFOUND: str = "The specified dynamic-link library was not found."; break; case SE_ERR_NOASSOC: str = "There is no application associated\nwith the given filename extension."; break; case SE_ERR_OOM: str = "There was not enough memory to complete the operation."; break; case SE_ERR_SHARE: str = "A sharing violation occurred. "; default: str.Format("Unknown Error (%d) occurred.", nError); break; } str = "Unable to open hyperlink:\n\n" + str; AfxMessageBox(str, MB_ICONEXCLAMATION | MB_OK); } HINSTANCE CMapHyperLink::GotoURL(LPCTSTR url, int showcmd) { TCHAR key[MAX_PATH + MAX_PATH]; // First try ShellExecute() HINSTANCE result = ShellExecute(NULL, _T("open"), url, NULL,NULL, showcmd); // If it failed, get the .htm regkey and lookup the program if ((UINT)result <= HINSTANCE_ERROR) { if (GetRegKey(HKEY_CLASSES_ROOT, _T(".htm"), key) == ERROR_SUCCESS) { lstrcat(key, _T("\shell\open\command")); if (GetRegKey(HKEY_CLASSES_ROOT,key,key) == ERROR_SUCCESS) { TCHAR *pos; pos = _tcsstr(key, _T(""%1"")); if (pos == NULL) { // No quotes found pos = strstr(key, _T("%1")); // Check for %1, without quotes if (pos == NULL) // No parameter at all... pos = key+lstrlen(key)-1; else *pos = '\0'; // Remove the parameter } else *pos = '\0'; // Remove the parameter lstrcat(pos, _T(" ")); lstrcat(pos, url); result = (HINSTANCE) WinExec(key,showcmd); } } } return result; } ///////////////////////////////////////////////////////////////////////////////////// BOOL CTestDlg::OnInitDialog() { CDialog::OnInitDialog(); // Set the icon for this dialog. The framework does this automatically // when the application's main window is not a dialog SetIcon(m_hIcon, TRUE); // Set big icon SetIcon(m_hIcon, FALSE); // Set small icon //設(shè)置圖形的超鏈接 m_MapHyperLink1.SetURL("www.yesky.com"); m_MapHyperLink1.SetTipText("歡迎訪問天極網(wǎng)"); // TODO: Add extra initialization here return TRUE; // return TRUE unless you set the focus to a control } |
四、小結(jié)
本實(shí)例通過介紹如何實(shí)現(xiàn)超鏈接功能，介紹了工具提示、動態(tài)地從可執(zhí)行文件中加載圖標(biāo)、使用外殼函數(shù)ShellExecute（）等知識，甚至還包括注冊表的操作等內(nèi)容，應(yīng)該說雖然程序比較簡單，但包含的內(nèi)容還是比較豐富的。最后，運(yùn)行此程序，將在對話框上顯示"天極網(wǎng)"的首頁鏈接，在圖像上點(diǎn)鼠標(biāo)左鍵后將自動進(jìn)入天極網(wǎng)首頁，效果很理想。