⭐ 欢迎来到虫虫下载站！ | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站
📤 上传资源

📄 magnitudetree-3-6.html

📁 构建定制的树型视图
💻 HTML
📖 第 1 页 / 共 2 页
字号:
🔍
12 
      {
        if (browser=="N3")document[image].src=eval(image + "out.src");
      }
      function iOver(image)
      {
        if (browser=="N3")document[image].src=eval(image + "over.src");
      }
     // --></script><!-- <script src="../i/emailfriend.js" language="javascript"></script> --><a href="#navskip"><img border="0" alt="跳至主要内容" src="../i/c.gif"></a>
        <table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr bgcolor="#006699">
<td><table width="300" border="0" cellspacing="0" cellpadding="0">
<tr bgcolor="#006699">
<td width="150"><img src="../i/mast_logo.gif" alt="IBM" width="150" height="25"/></td>
<td width="150" background="../i/mgradient.gif"><font size="2" color="#99ccff" face="宋体"><b>中国</b></font><br /> <img src="../i/c.gif" width="150" height="1" alt=""/></td>
</tr></table> 
</td>
<td align="left"><table width="300" border="0" cellspacing="0" cellpadding="0">
<tr>
<td width="100"><a href="/cgi-bin/click.p?url=http://www.ibm.com/cn/shop"><img border="0" src="../i/shopibm.gif" width="100" height="25" alt="购物"/></a></td>
<td width="100"><a href="/cgi-bin/click.p?url=http://www.ibm.com/cn/support"><img border="0" src="../i/support_chs.gif" width="100" height="25" alt="技术支持"/></a></td>
<td width="100"><a href="/cgi-bin/click.p?url=http://www.ibm.com/cn/support/product"><img border="0" src="../i/downloads_chs.gif" width="100" height="25" alt="免费下载"/></a></td></tr></table>
</td></tr></table>
<table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr bgcolor="#000000">
<td><table width="600" border="0" cellspacing="0" cellpadding="0">
<tr><td bgcolor="#006699" width="150"><img src="../i/mast_lnav_sp.gif" width="150" height="21" alt=""/></td>
<td colspan="4" bgcolor="#000000"><table border="0" cellspacing="0" cellpadding="0" height="21">
<tr>
<td height="21" bgcolor="#000000" width="79" align="center"><a class="nav" style="color: #ffffff;" href="/cgi-bin/click.p?url=http://www.ibm.com/cn"><font size="2" color="#ffffff" face="宋体"><b>IBM 主页</b></font></a></td>
<td bgcolor="#959595" width="1"><img src="../i/c.gif" width="1" height="1" alt=""/></td>
<td height="21" bgcolor="#000000" width="74" align="center"><a class="nav" style="color: #ffffff;" href=/cgi-bin/click.p?url=http://www.ibm.com/cn/products><font size="2" color="#ffffff" face="宋体"><b>产品</b></font></a></td>
<td bgcolor="#959595" width="1"><img src="../i/c.gif" width="1" height="1" alt=""/></td>
<td height="21" bgcolor="#000000" width="81" align="center"><a class="nav" style="color: #ffffff;" href="/cgi-bin/click.p?url=http://www.ibm.com/cn/services"><font size="2" color="#ffffff" face="宋体"><b>咨询</b></font></a></td><td bgcolor="#959595" width="1"><img src="../i/c.gif" width="1" height="1" alt=""/></td>
<td height="21" bgcolor="#000000" width="81" align="center"><a class="nav" style="color: #ffffff;" href="/cgi-bin/click.p?url=http://www.ibm.com/cn/industry"><font size="2" color="#ffffff" face="宋体"><b>行业</b></font></a></td>
<td bgcolor="#959595" width="1"><img src="../i/c.gif" width="1" height="1" alt=""/></td>
<td height="21" bgcolor="#000000" width="57" align="center"><a class="nav" style="color: #ffffff;" href="/cgi-bin/click.p?url=http://www.ibm.com/cn/news"><font size="2" color="#ffffff" face="宋体"><b>新闻</b>
                                                </font></a></td>
<td bgcolor="#959595" width="1"><img src="../i/c.gif" width="1" height="1" alt=""/></td>
<td height="21" bgcolor="#000000" width="78" align="center"><a class="nav" style="color: #ffffff;" href="/cgi-bin/click.p?url=http://www.ibm.com/cn/ibm"><font size="2" color="#ffffff" face="宋体"><b>关于 IBM</b>
                                                </font></a></td></tr></table></td></tr></table></td></tr></table><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD width="150" height="1" bgcolor="#ffffff"><IMG alt="" height="1" width="150" src="../i/c.gif"></TD></TR><TR><TD width="150" height="3" bgcolor="#cc6633"><IMG alt="" height="3" width="150" src="../i/c.gif"></TD></TR><TR><TD width="150" height="1" bgcolor="#333333"><IMG alt="" height="1" width="150" src="../i/c.gif"></TD></TR><TR><TD width="150" height="1" bgcolor="#000000"><IMG alt="" height="1" width="150" src="../i/c.gif"></TD></TR></TABLE><table border="0" cellpadding="0" cellspacing="0" width="100%"><tr><td><font face="Verdana, sans-serif" size="-1"><a href="/cgi-bin/click.p?url=http://www.ibm.com/cn">IBM</a> : <a
href="/developerWorks/">developerWorks 中国</a> : <a
href="/developerWorks/java/">Java</a> : <a
href="/developerWorks/education/java/">教学 - 在线课程</a></font><br x="7"><img src="imagemaster/masthead.jpg" alt="构建定制的树型视图"></td><td width="*" valign="bottom" align="right"><a border="0" href="../MagnitudeTree.zip"><img alt="下载教程 zip 文件" border="0" src="../i/icon-zip.gif"></a><a href=../MagnitudeTree_eng/index.html target=_blank><img alt="英文原文" border="0" src="../i/icon-source.gif"></a></td></tr><tr><td height="2" colspan="2"><img height="2" width="1" src="../i/c.gif"></td></tr></table><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD width="150" height="1" bgcolor="#000000" colspan="6"><IMG alt="" height="1" width="150" src="../i/c.gif"></TD></TR><TR><TD background="../i/sw-gold.gif"><a border="0" href="index.html" onMouseOver="iOver('topmain'); iOver('bottommain'); self.status=mainblurb; return true;" onMouseOut="iOut('topmain'); iOut('bottommain'); self.status=''; return true;"><img alt="主菜单" border="0" src="../i/main.gif" name="topmain"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topsection'); iOver('bottomsection'); self.status=sectionblurb; return true;" onMouseOut="iOut('topsection'); iOut('bottomsection'); self.status=''; return true;" href="index3.html"><img alt="章节菜单" border="0" src="../i/section.gif" name="topsection"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topfeedback'); iOver('bottomfeedback'); self.status=feedbackblurb; return true;" onMouseOut="iOut('topfeedback'); iOut('bottomfeedback'); self.status=''; return true;" href="MagnitudeTree-7-4.html"><img alt="提交反馈意见" border="0" src="../i/feedback.gif" name="topfeedback"></a></TD><TD width="100%" background="../i/sw-gold.gif"><img src="../i/c.gif"></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topprevious'); iOver('bottomprevious'); self.status=previousblurb; return true;" onMouseOut="iOut('topprevious'); iOut('bottomprevious'); self.status=''; return true;" href="MagnitudeTree-3-5.html"><img alt="上一屏" border="0" src="../i/previous.gif" name="topprevious"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topnext'); iOver('bottomnext'); self.status=nextblurb; return true;" onMouseOut="iOut('topnext'); iOut('bottomnext'); self.status=''; return true;" href="MagnitudeTree-3-7.html"><img alt="下一屏" border="0" src="../i/next.gif" name="topnext"></a></TD></TR></TABLE><table bgcolor="ffffff" cellspacing="0" cellpadding="2" border="0" height="400" width="100%"><tr valign="bottom"><a name="navskip"></a><td height="25" colspan="4"><img border="0" height="25" width="562" src="imagemaster/titlebar3.jpg" alt="3. 定制模型"></td></tr><tr><td bgcolor="ffffff" width="15">&nbsp;</td><td bgcolor="ffffff" width="12">&nbsp;</td><td valign="top" align="left" bgcolor="ffffff" width="*"><p><br x="7"><table cellspacing="0" cellpadding="0" border="0"><tr><td width="90%"><font size="4" face="Verdana, Arial, Helvetica"><b>使树节点类通用</b></font></td><td width="200" align="right"><font size="1" face="Verdana, Arial, Helvetica"><nobr>    第 6 页（共 9 页）</nobr></font></td></tr></table><br x="7"><br x="7"></p><font size="2" face="Verdana, Arial, Helvetica"><p>
DefaultMagnitudeNode 类的实用性取决于它是否对于要在树型视图中显示的每个层次结构可重用。DefaultMagnitudeNode 类需要了解关于它表示的节点的某些重要事实，这些事实是：
<ul><li>树型视图中要显示的节点的文本表示法
</li><li>节点是否是容器，这将确定树型视图中节点的视觉显示
</li><li>要存储在 DefaultMagnitudeNode 的 <code
style="font-family: Courier New, Courier, monospace; font-size:
12">fSize</code> 数据成员中的节点“大小”</li></ul>
          </p><p>
有几种方法可以获取这些事实：
<ol>
              <li>DefaultMagnitudeNode 类可以用抽象方法来返回该信息，而且必须按专门节点的不同类型来提供方法。</li>
              <li>DefaultMagnitudeNode 类可以按参数形式将此信息接收到它的构造器中，或者以调用方式将此信息接收到合适的方法中，以设置值。</li>
              <li>可以指定 "helper" 对象来提供关于每个节点的此类信息。</li>
            </ol>
          </p><p>
本教程使用第三个选项，因此要介绍为支持本教程创建的另一个定制组件：<b>MagnitudeNodeHelper</b>
接口，它拥有用于提供必要信息的方法。本章节的后续部分中，将利用该设计模式来提供一些附加好处。DefaultMutableTreeNode
类提供了与每个节点相关的<b>用户对象</b>的概念，我们通过将用户对象作为向
helper 对象询问必要信息的键。</p><p>
此阶段中的 MagnitudeNodeHelper 接口看上去就像：
<pre><code style="font-family: Courier New, Courier, monospace; font-size: 12">
<span class="keyword">public</span> <span class="keyword">interface</span> <span class="type">MagnitudeNodeHelper</span>
{
  <span class="comment">/** Return the size of the node represented by the supplied user object,
    * excluding the size of any children.
    * @param object the information store specific object for a node.
    * @return long the size of the represented node. */</span>
  <span class="keyword">public</span> <span class="type">long</span> <span class="function-name">getSize</span>(<span class="type">Object</span> <span class="variable-name">object</span>);

  <span class="comment">/** Return whether the node represented by the supplied user object
    * is a container. Nodes which are capable of containing other nodes
    * are given a different representation in the JTree.
    * @param object the information-store-specific object for a node.
    * @return boolean indicating whether the represented node is a
    * container. */</span>
  <span class="keyword">public</span> <span class="type">boolean</span> <span class="function-name">isContainer</span>(<span class="type">Object</span> <span class="variable-name">object</span>);

  <span class="comment">/** Return a string representation of the node represented by the
    * supplied user object.
    * @param object the information-store-specific object for a node.
    * @return String the string representation of a node. */</span>
  <span class="keyword">public</span> <span class="type">String</span> <span class="function-name">toString</span>(<span class="type">Object</span> <span class="variable-name">object</span>);
}
            </code></pre>
          </p><p>
helper 对象被提供给 DefaultMagnitudeNode 构造器，而且被保存以供将来引用。请注意，当构造层次结构中的所有节点时，可以使用相同的 helper 对象实例，只要它可以使用每个节点的用户对象作为必需实例的密钥。这里是 DefaultMagnitudeNode 类和新构造器的必要附加数据成员：
<pre><code style="font-family: Courier New, Courier, monospace; font-size: 12">
<span class="comment">// The helper instance for this magnitude node.</span>
<span class="keyword">private</span> <span class="keyword">final</span> <span class="type">MagnitudeNodeHelper</span> <span class="variable-name">fHelper</span>;

<span class="keyword">public</span> <span class="function-name">DefaultMagnitudeNode</span>(<span class="keyword">final</span> <span class="type">Object</span> <span class="variable-name">userObject</span>,
                            <span class="keyword">final</span> <span class="type">MagnitudeNodeHelper</span> <span class="variable-name">helper</span>)
{
  <span class="comment">// Store the user object and helper.</span>
  <span class="function-name">super</span>(<span class="variable-name">userObject</span>);
  <span class="variable-name">fHelper</span> = <span class="variable-name">helper</span>;

  // Ask our helper for our size.
  <span class="variable-name">fSize</span> = <span class="variable-name">helper</span>.<span class="function-name">getSize</span>(<span class="variable-name">userObject</span>);

  // Initialize our aggregate size to the size of our self.
  // The sizes of our descendants will be added later.
  <span class="variable-name">fAggregateSize</span> = <span class="variable-name">fSize</span>;

  // Initialize our aggregate count to 0, or 1 if we are a leaf.
  // The number of our non-container descendants will be added later.
  <span class="variable-name">fAggregateCount</span> = <span class="variable-name">helper</span>.<span class="function-name">isContainer</span>(<span class="variable-name">userObject</span>) ? <span class="constant">0</span> : <span class="constant">1</span>;
}
            </code></pre>
          </p><p>
请注意，<code style="font-family: Courier New, Courier,
monospace; font-size: 12">fAggregateSize</code> 数据成员初始化成节点本身的大小。下一页将描述如何增加合计值以包括所有子代节点的大小。
          </p><br x="7"></font></td></tr></table><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD background="../i/sw-gold.gif"><a border="0" href="index.html" onMouseOver="iOver('topmain'); iOver('bottommain'); self.status=mainblurb; return true;" onMouseOut="iOut('topmain'); iOut('bottommain'); self.status=''; return true;"><img alt="主菜单" border="0" src="../i/main.gif" name="bottommain"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topsection'); iOver('bottomsection'); self.status=sectionblurb; return true;" onMouseOut="iOut('topsection'); iOut('bottomsection'); self.status=''; return true;" href="index3.html"><img alt="章节菜单" border="0" src="../i/section.gif" name="bottomsection"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topfeedback'); iOver('bottomfeedback'); self.status=feedbackblurb; return true;" onMouseOut="iOut('topfeedback'); iOut('bottomfeedback'); self.status=''; return true;" href="MagnitudeTree-7-4.html"><img alt="提交反馈意见" border="0" src="../i/feedback.gif" name="bottomfeedback"></a></TD><TD width="100%" background="../i/sw-gold.gif"><img src="../i/c.gif"></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topprevious'); iOver('bottomprevious'); self.status=previousblurb; return true;" onMouseOut="iOut('topprevious'); iOut('bottomprevious'); self.status=''; return true;" href="MagnitudeTree-3-5.html"><img alt="上一屏" border="0" src="../i/previous.gif" name="bottomprevious"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topnext'); iOver('bottomnext'); self.status=nextblurb; return true;" onMouseOut="iOut('topnext'); iOut('bottomnext'); self.status=''; return true;" href="MagnitudeTree-3-7.html"><img alt="下一屏" border="0" src="../i/next.gif" name="bottomnext"></a></TD></TR><TR><TD width="150" height="1" bgcolor="#000000" colspan="6"><IMG alt="" height="1" width="150" src="../i/c.gif"></TD></TR></TABLE><TABLE cellpadding="0" cellspacing="0" border="0"><TR><TD width="182"><TABLE cellpadding="0" cellspacing="0" border="0" width="182">
            <TR bgcolor="#000000"><TD align="center" width="60" class="mast"><a style="text-decoration: none; color: #ffffff;" class="nav" href="http://www.ibm.com/privacy/"><font face="Arial, Verdana" size="2">隐私</font></a></TD>
            <TD width="1" bgcolor="#959595"><img alt="" border="0" height="20" width="1" src="../i/c.gif"></TD>
            <TD align="center" width="60" class="mast"><a style="text-decoration: none; color: #ffffff;" class="nav" href="http://www.ibm.com/legal/"><font face="Arial, Verdana" size="2">法律</font></a></TD>
            <TD width="1" bgcolor="#959595"><img alt="" border="0" height="20" width="1" src="../i/c.gif"></TD>
            <TD align="center" width="60" class="mast"><a style="text-decoration: none; color: #ffffff;" class="nav" href="http://www.ibm.com/contact/"><font face="Arial, Verdana" size="2">联系</font></a></TD>
            <TD width="1" bgcolor="#959595"><img alt="" border="0" height="21" width="1" src="../i/c.gif"></TD></TR><TR bgcolor="#ffffff"><TD><img alt="" border="0" height="1" width="1" src="../i/c.gif"></TD></TR></TABLE></TD><TD width="100%"><TABLE cellpadding="0" cellspacing="0" border="0" width="100%"><TR height="21" bgcolor="#000000"><TD><img alt="" border="0" height="21" width="1" src="../i/c.gif"></TD></TR><TR bgcolor="#ffffff"><TD><img alt="" border="0" height="1" width="1" src="../i/c.gif"></TD></TR></TABLE></TD></TR></TABLE></body></html>
12

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -