</center></div></b></font><font FACE="Times New Roman" SIZE="3"><p ALIGN="JUSTIFY"></font><font SIZE="3">修改完后，讀者可以編譯并運(yùn)行</font><font FACE="Times New Roman" SIZE="3">Record</font><font SIZE="3">，來看看修改的結(jié)果。讀者很快會(huì)注意到</font><font FACE="Times New Roman" SIZE="3">Start</font><font SIZE="3">和</font><font FACE="Times New Roman" SIZE="3">Stop</font><font SIZE="3">菜單項(xiàng)及按鈕都是灰色的。這個(gè)現(xiàn)象是正常的，其原因?qū)⒃?lt;/font><font FACE="Times New Roman" SIZE="3">4.2</font><font SIZE="3">節(jié)解釋。有趣的是工具條可以被拖動(dòng)（請(qǐng)?jiān)诠ぞ邨l的空白地方拖動(dòng)）并停泊在主框架窗口的任何其它邊上，并且工具條是可以浮動(dòng)的，即當(dāng)用鼠標(biāo)雙擊工具條的空白處時(shí)，工具條變成了一個(gè)浮動(dòng)窗口，可被拖動(dòng)到屏幕上的任意地方。這些有趣的現(xiàn)象將在</font><font FACE="Times New Roman" SIZE="3">4.2</font><font SIZE="3">節(jié)解釋。不管怎么說，創(chuàng)建和修改工具條的任務(wù)已經(jīng)完成了。</font><font FACE="Times New Roman" SIZE="3"></p>
    <b><p ALIGN="JUSTIFY"></b></font><font color="#3973DE" FACE="Times New Roman" SIZE="3">4.1.2</font><font SIZE="3" color="#3973DE">手工創(chuàng)建</font><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">如果想要再加一個(gè)工具條，那么</font><font FACE="Times New Roman" SIZE="3">AppWizard</font><font SIZE="3">就無能為力了，必須手工創(chuàng)建。假設(shè)</font><font FACE="Times New Roman" SIZE="3">Record</font><font SIZE="3">程序的聲音采樣頻率有</font><font FACE="Times New Roman" SIZE="3">11KHZ</font><font SIZE="3">和</font><font FACE="Times New Roman" SIZE="3">44KHZ</font><font SIZE="3">兩檔選擇，現(xiàn)在我們的任務(wù)是再創(chuàng)建一個(gè)工具條，可讓用戶對(duì)這兩種檔次進(jìn)行選擇。本來這樣的功能應(yīng)該位于第一個(gè)工具條內(nèi)，但為了演示工具條的手工創(chuàng)建，這里不妨來個(gè)多此一舉。</font><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">如果</font><font FACE="Times New Roman" SIZE="3">Record</font><font SIZE="3">工程不在</font><font FACE="Times New Roman" SIZE="3">Developer Studio</font><font SIZE="3">中，請(qǐng)選擇命令</font><font FACE="Times New Roman" SIZE="3">File-&gt;Open Workspace</font><font SIZE="3">打開</font><font FACE="Times New Roman" SIZE="3">Record</font><font SIZE="3">工程。首先要對(duì)原來的菜單進(jìn)行修改，步驟如下：</p>
    <blockquote>
      <ol>
        <li><p ALIGN="JUSTIFY">打開<font FACE="Times New Roman" SIZE="3">IDR_MAINFRAME</font>菜單資源</p>
        </li>
        <li><p ALIGN="JUSTIFY">雙擊<font FACE="Times New Roman" SIZE="3">Record</font>菜單底端的空白項(xiàng)，在其屬性窗口中選中<font FACE="Times New Roman" SIZE="3">Separator</font>，這樣就加入了一條分隔線。</p>
        </li>
        <li><p ALIGN="JUSTIFY">在分隔線下面加入兩個(gè)菜單項(xiàng)，其屬性如表<font FACE="Times New Roman" SIZE="3">4.1</font>所示。</p>
        </li>
      </ol>
    </blockquote>
    </font><p>　<b><font SIZE="3"></p>
    <p ALIGN="CENTER">表</font><font FACE="Times New Roman" SIZE="3">4.1 </font><font SIZE="3">菜單項(xiàng)的屬性</font></b></p>
    <table BORDER="1" CELLSPACING="1" CELLPADDING="1" WIDTH="579">
      <tr>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">Caption</font></td>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">ID</font></td>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">Prompt</font></td>
      </tr>
      <tr>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">&amp;Low quality</font></td>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">ID_LOW_QUALITY</font></td>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">Low 
        quality(11k)\n11k</font></td>
      </tr>
      <tr>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">&amp;High quality</font></td>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">ID_HIGH_QUALITY</font></td>
        <td WIDTH="33%"><font FACE="Times New Roman" SIZE="3"><p ALIGN="CENTER">High 
        quality(44k)\n44k</font></td>
      </tr>
    </table>
    <font FACE="Times New Roman" SIZE="3"><p ALIGN="JUSTIFY"></font><font SIZE="3">接著要?jiǎng)?chuàng)建一個(gè)新的工具條資源，請(qǐng)按以下步驟進(jìn)行：</p>
    <blockquote>
      <blockquote>
        <p ALIGN="JUSTIFY">選擇</font><font FACE="Times New Roman" SIZE="3">Insert-&gt;Resource</font><font SIZE="3">命令，然后在</font><font FACE="Times New Roman" SIZE="3">Insert Resource</font><font SIZE="3">對(duì)話框中選中</font><font FACE="Times New Roman" SIZE="3">Toolbar</font><font SIZE="3">。按了</font><font FACE="Times New Roman" SIZE="3">OK</font><font SIZE="3">按鈕后，在</font><font FACE="Times New Roman" SIZE="3">Toolbar</font><font SIZE="3">資源類下就會(huì)出現(xiàn)一個(gè)</font><font FACE="Times New Roman" SIZE="3">ID</font><font SIZE="3">為</font><font FACE="Times New Roman" SIZE="3">IDR_TOOLBAR1</font><font SIZE="3">的新資源。</p>
        <p ALIGN="JUSTIFY">在新工具條中加入兩個(gè)按鈕，如圖</font><font FACE="Times New Roman" SIZE="3">4.5</font><font SIZE="3">所示。每個(gè)按鈕上都畫了一些豎線，線稀的按鈕代表低頻率采樣，線密的按鈕代表高頻率采樣。</p>
        <p ALIGN="center"><img src="T4_5.gif" alt="T4_5.tif (115754 bytes)" WIDTH="459" HEIGHT="234"></p>
        <p ALIGN="center">圖</font><font FACE="Times New Roman" SIZE="3">4.5 </font><font SIZE="3">新創(chuàng)建的工具條資源</p>
        <p ALIGN="JUSTIFY">分別為兩個(gè)新加的按鈕指定命令</font><font FACE="Times New Roman" SIZE="3">ID</font><font SIZE="3">為</font><font FACE="Times New Roman" SIZE="3">ID_LOW_QUALITY</font><font SIZE="3">和</font><font FACE="Times New Roman" SIZE="3">ID_HIGH_QUALITY</font><font SIZE="3">。</font></p>
      </blockquote>
    </blockquote>
    <p>　<font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">要把這個(gè)新設(shè)計(jì)的工具條加入到程序中，需要在程序中加入一些與創(chuàng)建有關(guān)的源代碼。在創(chuàng)建第一個(gè)工具條時(shí)，</font><font FACE="Times New Roman" SIZE="3">AppWizard</font><font SIZE="3">在程序中自動(dòng)加入了創(chuàng)建源代碼，通過仿制這些代碼，我們很容易創(chuàng)建出第二個(gè)工具條。</font><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">在</font><font FACE="Times New Roman" SIZE="3">MFC</font><font SIZE="3">中，工具條的功能由類</font><font FACE="Times New Roman" SIZE="3">CToolBar</font><font SIZE="3">實(shí)現(xiàn)。工具條實(shí)際上是主框架窗口的子窗口，因此工具條對(duì)象應(yīng)該依附于主框架窗口對(duì)象。在</font><font FACE="Times New Roman" SIZE="3">AppWizard</font><font SIZE="3">創(chuàng)建的</font><font FACE="Times New Roman" SIZE="3">MFC</font><font SIZE="3">程序中，主框架窗口的類名是</font><font FACE="Times New Roman" SIZE="3">CMainFrame</font><font SIZE="3">，該類是</font><font FACE="Times New Roman" SIZE="3">MFC</font><font SIZE="3">標(biāo)準(zhǔn)類</font><font FACE="Times New Roman" SIZE="3">CFrameWnd</font><font SIZE="3">類的派生類。將項(xiàng)目工作區(qū)切換至類視圖并展開</font><font FACE="Times New Roman" SIZE="3">CMainFrame</font><font SIZE="3">類，讀者會(huì)發(fā)現(xiàn)該類有一個(gè)名為</font><font FACE="Times New Roman" SIZE="3">m_wndToolbar</font><font SIZE="3">的成員。雙擊該成員，則</font><font FACE="Times New Roman" SIZE="3">Developer Studio</font><font SIZE="3">會(huì)自動(dòng)打開類</font><font FACE="Times New Roman" SIZE="3">CMainFrame</font><font SIZE="3">所在的頭文件，并將光標(biāo)停在對(duì)</font><font FACE="Times New Roman" SIZE="3">m_wndToolbar</font><font SIZE="3">成員的定義處。</font><font FACE="Times New Roman" SIZE="3"></p>
    <div align="center"><center><table border="2" cellpadding="2" cellspacing="0" width="90%" bgcolor="#BBFFFF">
      <tr>
        <td width="100%"></font><b><font SIZE="3"><font SIZE="3">提示</font></font><font FACE="Times New Roman" SIZE="3">:</font><font SIZE="3"><font SIZE="3">在類視圖中雙擊某一個(gè)類名，則該類所在的頭文件會(huì)自動(dòng)打開。若雙擊某一個(gè)類的成員，則會(huì)自動(dòng)切換到對(duì)該成員的定義處。</font></font></b><font FACE="Times New Roman" SIZE="3"></td>
      </tr>
    </table>
    </center></div><p ALIGN="JUSTIFY">　</p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">　</font><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">對(duì)</font><font FACE="Times New Roman" SIZE="3">m_wndToolBar</font><font SIZE="3">的定義如下：</font><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY">CToolBar m_wndToolBar;</p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">由此可見</font><font FACE="Times New Roman" SIZE="3">m_wndToolBar</font><font SIZE="3">是一個(gè)</font><font FACE="Times New Roman" SIZE="3">CToolBar</font><font SIZE="3">對(duì)象，它是</font><font FACE="Times New Roman" SIZE="3">CMainFrame</font><font SIZE="3">的成員?，F(xiàn)在請(qǐng)緊接著該成員加入一個(gè)新的成員：</font><font FACE="Times New Roman" SIZE="3"><b></p>
    <p ALIGN="JUSTIFY">CToolBar m_wndToolBar1;</b></p>
    <p ALIGN="JUSTIFY">m_wndToolBar1</font><font SIZE="3">代表第二個(gè)工具條。讀者不要以為給</font><font FACE="Times New Roman" SIZE="3">CMainFrame</font><font SIZE="3">加入一個(gè)</font><font FACE="Times New Roman" SIZE="3">CToolBar</font><font SIZE="3">對(duì)象就完事了。實(shí)際的創(chuàng)建工具條的工作不會(huì)在構(gòu)造</font><font FACE="Times New Roman" SIZE="3">CToolBar</font><font SIZE="3">對(duì)象時(shí)完成，只有調(diào)用了類</font><font FACE="Times New Roman" SIZE="3">CToolBar</font><font SIZE="3">的一些成員函數(shù)后，創(chuàng)建工作才能結(jié)束。</font><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">　</font><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font><font SIZE="3">對(duì)工具條的實(shí)際創(chuàng)建工作在</font><font FACE="Times New Roman" SIZE="3">CMainFrame::OnCreate</font><font SIZE="3">函數(shù)中完成。</font><font FACE="Times New Roman" SIZE="3">OnCreate</font><font SIZE="3">函數(shù)是在創(chuàng)建窗口時(shí)被調(diào)用的，這時(shí)窗口的創(chuàng)建已部分完成，窗口對(duì)象的</font><font FACE="Times New Roman" SIZE="3">m_hWnd</font><font SIZE="3">成員中存放的</font><font FACE="Times New Roman" SIZE="3">HWND</font><font SIZE="3">句柄也已有效，但窗口還是不可見的。因此一般在</font><font FACE="Times New Roman" SIZE="3">OnCreate</font><font SIZE="3">函數(shù)中作一些諸如創(chuàng)建子窗口的初始化工作。</font><font FACE="Times New Roman" SIZE="3"></p>
    </font><font SIZE="3"><b><div align="center"><center><table border="2" cellpadding="2" cellspacing="0" width="90%" bgcolor="#BBFFFF">
      <tr>
        <td width="100%"></b>提示</font><font FACE="Times New Roman" SIZE="3">:</font><font SIZE="3">初學(xué)者一個(gè)易犯的錯(cuò)誤是在構(gòu)造函數(shù)而不是在</font><font FACE="Times New Roman" SIZE="3">OnCreate</font><font SIZE="3">中創(chuàng)建子窗口。在構(gòu)造函數(shù)中，父窗口并沒有創(chuàng)建，如果在這時(shí)創(chuàng)建子窗口，則將會(huì)因?yàn)榈貌坏礁复翱诘挠行?lt;/font><font FACE="Times New Roman" SIZE="3">HWND</font><font SIZE="3">句柄而導(dǎo)致創(chuàng)建失敗。<b></td>
      </tr>
    </table>
    </center></div></b></font><font FACE="Times New Roman" SIZE="3"><p ALIGN="JUSTIFY"></font><font SIZE="3">找到</font><font FACE="Times New Roman" SIZE="3">CMainFrame::OnCreate</font><font SIZE="3">函數(shù)，對(duì)該函數(shù)進(jìn)行一些修改，修改的部分如清單</font><font FACE="Times New Roman" SIZE="3">4.1</font><font SIZE="3">的黑體字所示。在以后，凡是程序中手工修改的部分，一般都會(huì)用黑體顯示。</font><b><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY"></font>　<font SIZE="3"></p>
    <p ALIGN="JUSTIFY">清單</font><font FACE="Times New Roman" SIZE="3">4.1 </font><font SIZE="3">修改后的</font><font FACE="Times New Roman" SIZE="3">CMainFrame::OnCreate</font><font SIZE="3">函數(shù)</font></b><font FACE="Times New Roman" SIZE="3"></p>
    <p ALIGN="JUSTIFY">int CMainFrame::OnCreate(LPCREATESTRUCT lpCreateStruct)</p>
    <p ALIGN="JUSTIFY">{</p>
    <p ALIGN="JUSTIFY">if (CFrameWnd::OnCreate(lpCreateStruct) == -1)</p>
    <p ALIGN="JUSTIFY">return -1;</p>
    <p ALIGN="JUSTIFY">　</p>
    <p ALIGN="JUSTIFY">if (!m_wndToolBar.Create(this) ||</p>
    <p ALIGN="JUSTIFY">!m_wndToolBar.LoadToolBar(IDR_MAINFRAME))</p>
    <p ALIGN="JUSTIFY">{</p>
    <p ALIGN="JUSTIFY">TRACE0(&quot;Failed to create toolbar\n&quot;);</p>
    <p ALIGN="JUSTIFY">return -1; // fail to create</p>
    <p ALIGN="JUSTIFY">}</p>
    <p ALIGN="JUSTIFY">　</p>
    <p>　<b></p>
    <p ALIGN="JUSTIFY">if (!m_wndToolBar1.Create(this) ||</p>
    <p ALIGN="JUSTIFY">!m_wndToolBar1.LoadToolBar(IDR_TOOLBAR1))</p>
    <p ALIGN="JUSTIFY">{</p>