[pde-dev] Hello World Plugin doesn't work,please help!

["邹志乐" <zouzhile@xxxxxxx>]

Hi,I followed the "Platform plug-in developer guide" to try the "HelloWorldView" sample out.I got the following plugin.xml:

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.0"?>
<plugin
   id="com.example.helloworld"
   name="Helloworld Plug-in"
   version="1.0.0"
   provider-name="EXAMPLE"
   class="com.example.helloworld.HelloworldPlugin">

   <runtime>
      <library name="HelloWorldPlugin.jar">
         <export name="*"/>
      </library>
   </runtime>

   <requires>
      <import plugin="org.eclipse.ui"/>
      <import plugin="org.eclipse.core.runtime"/>
   </requires>

   <extension
         point="org.eclipse.ui.views">
      <category
            name="Hello Category"
            id="com.example.helloworld">
      </category>
      <view
            name="Hello View"
            icon="icons/sample.gif"
            category="com.example.helloworld"
            class="com.example.helloworld.views.HelloWorldView"
            id="com.example.helloworld.views.HelloWorldView">
      </view>
   </extension>

</plugin>
 
Firt,i tried to launch the runtime workbench,and it came out that the "HelloWorldView" plugin just worked without any problem.
Then i want to install it just as other plugin. As it says,i exported the plugin project to HelloWorldPlugin.jar under the "EXLIPSE_HOME/plugins/com.example.helloworld directory,and then export the plugin.xml to the same directory.It is very strange that after i restart my workbench, the error log indicates that the class  "com.example.helloworld.views.HelloWorldView" can not be loaded!I checked my the jar file,the class was just over there.so what is wrong please?and how to solve this problem.or maybe it is an plugin installation problem?
best regards!
robin

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