Eclipse插件开发自定义扩展点

• 介绍

如果你的插件写的有特色，想拿来用，但是还不能或者不适合直接修改你的代码，怎么办呢？解决方案当然是Eclipse插件系统最推荐的了——增加扩展点。

• 概念

一个扩展点（Extension Point）包括ID、Name及Schema文件，shema文件以ID命名，后缀为.exsd，存放在插件schema目录下。

• 定义

[codesyntax lang="xml"]

<?xml version='1.0' encoding='UTF-8'?><!-- Schema file written by PDE --><schema targetNamespace="org.suren.littlebird" xmlns="http://www.w3.org/2001/XMLSchema"><annotation>      <appinfo>         <meta.schema plugin="org.suren.littlebird" id="org.suren.littlebird.bundles.list" name="BundlesList"/>      </appinfo>      <documentation>         对bundle列表的扩展      </documentation>   </annotation>   <element name="extension">      <annotation>         <appinfo>            <meta.element />         </appinfo>      </annotation>      <complexType>         <attribute name="id" type="string">            <annotation>               <documentation>                                 </documentation>            </annotation>         </attribute>         <attribute name="point" type="string" use="required">            <annotation>               <documentation>                  测试啊               </documentation>            </annotation>         </attribute>         <attribute name="name" type="string">            <annotation>               <documentation>                                 </documentation>            </annotation>         </attribute>      </complexType>   </element>   <element name="column">      <annotation>         <documentation>            新增一列         </documentation>      </annotation>      <complexType>         <attribute name="text" type="string" use="required">            <annotation>               <documentation>                  列名               </documentation>            </annotation>         </attribute>         <attribute name="sorter" type="string">            <annotation>               <documentation>                                 </documentation>               <appinfo>                  <meta.attribute kind="java" basedOn="org.suren.littlebird.views.listener.SorterAdapter:"/>               </appinfo>            </annotation>         </attribute>      </complexType>   </element>   <element name="action">      <annotation>         <documentation>            对列表操作的扩展         </documentation>      </annotation>      <complexType>         <attribute name="reload" type="string">            <annotation>               <documentation>                                 </documentation>               <appinfo>                  <meta.attribute kind="java" basedOn="org.suren.littlebird.actions.bundle.SuRenBundleReload:"/>               </appinfo>            </annotation>         </attribute>         <attribute name="install" type="string">            <annotation>               <documentation>                                 </documentation>               <appinfo>                  <meta.attribute kind="java" basedOn="org.suren.littlebird.actions.bundle.SuRenBundleInstallAction:"/>               </appinfo>            </annotation>         </attribute>         <attribute name="uninstall" type="string">            <annotation>               <documentation>                                 </documentation>               <appinfo>                  <meta.attribute kind="java" basedOn="org.suren.littlebird.actions.bundle.SuRenBundleUninstallAction:"/>               </appinfo>            </annotation>         </attribute>         <attribute name="update" type="string">            <annotation>               <documentation>                                 </documentation>               <appinfo>                  <meta.attribute kind="java" basedOn="org.suren.littlebird.actions.bundle.SuRenBundleUpdateAction:"/>               </appinfo>            </annotation>         </attribute>         <attribute name="start" type="string">            <annotation>               <documentation>                                 </documentation>               <appinfo>                  <meta.attribute kind="java" basedOn="org.suren.littlebird.actions.bundle.SuRenBundleStartAction:"/>               </appinfo>            </annotation>         </attribute>         <attribute name="stop" type="string">            <annotation>               <documentation>                  停止bundle               </documentation>               <appinfo>                  <meta.attribute kind="java" basedOn="org.suren.littlebird.actions.bundle.SuRenBundleStopAction:"/>               </appinfo>            </annotation>         </attribute>      </complexType>   </element>   <annotation>      <appinfo>         <meta.section type="since"/>      </appinfo>      <documentation>         [Enter the first release in which this extension point appears.]      </documentation>   </annotation>   <annotation>      <appinfo>         <meta.section type="examples"/>      </appinfo>      <documentation>         [Enter extension point usage example here.]      </documentation>   </annotation>   <annotation>      <appinfo>         <meta.section type="apiinfo"/>      </appinfo>      <documentation>         [Enter API information here.]      </documentation>   </annotation>   <annotation>      <appinfo>         <meta.section type="implementation"/>      </appinfo>      <documentation>         [Enter information about supplied implementation of this extension point.]      </documentation>   </annotation>   <annotation>      <appinfo>         <meta.section type="copyright"/>      </appinfo>      <documentation>         http://surenpi.com      </documentation>   </annotation></schema>

[/codesyntax]

上面的定义文件org.suren.littlebird.bundles.list.exsd，放在schema目录中。

• 注册

[codesyntax lang="xml"]

<?xml version="1.0" encoding="UTF-8"?><?eclipse version="3.4"?><plugin>   <extension-point id="org.suren.littlebird.bundles.list" name="BundlesList" schema="schema/org.suren.littlebird.bundles.list.exsd"/></plugin>

[/codesyntax]

上面的文件是plugin.xml

• 挂载扩展点

[codesyntax lang="java"]

private void regExtension(){IExtensionRegistry reg = Platform.getExtensionRegistry();IConfigurationElement[] extensions = reg.getConfigurationElementsFor("org.suren.littlebird.bundles.list");if(extensions != null){for(IConfigurationElement ele : extensions){if("column".equals(ele.getName())){String textAttr = ele.getAttribute("text");String sorterCls = ele.getAttribute("sorter");TableColumn col = new TableColumn(table, SWT.None);col.setText(textAttr);try {SorterAdapter ext = (SorterAdapter) WorkbenchPlugin.createExtension(ele, "sorter");ext.setViewer(viewer);col.addSelectionListener(ext);} catch (CoreException e) {e.printStackTrace();}}}}}

[/codesyntax]

• 使用扩展点

这时候，你需要新建一个插件工程，不知道怎么新建插件工程？这里有入门教程。

[codesyntax lang="xml"]

<?xml version="1.0" encoding="UTF-8"?><?eclipse version="3.4"?><plugin>   <extension         point="org.suren.littlebird.bundles.list">         <column text="test" sorter="test.extension.TestSorter"/>         <column text="two" />   </extension></plugin>

[/codesyntax]

 

上面的类test.extension.TestSorter是对列排序的扩展，然后增加了两列——test、two。

• 参考

http://www.cnblogs.com/maxupeng/archive/2011/07/27/2118975.html

查看原文：http://surenpi.com/2015/07/10/eclipse%e6%8f%92%e4%bb%b6%e5%bc%80%e5%8f%91%e8%87%aa%e5%ae%9a%e4%b9%89%e6%89%a9%e5%b1%95%e7%82%b9/