关于在ActivityManifest.xml注册活动的问题

只写一个application，而且只能有一个。

结构:

 <?xmlversion="1.0"encoding="utf-8"?>

<manifest>

    <application>

       <activity>

           <intent-filter>

               <action/>

               <category/>

           </intent-filter>

      </activity>

       <activity-alias>

           <intent-filter></intent-filter>

           <meta-data/>

      </activity-alias>

       <service>

           <intent-filter></intent-filter>

           <meta-data/>

       </service>

       <receiver>

           <intent-filter></intent-filter>

           <meta-data/>

       </receiver>

       <provider>

           <grant-uri-permission/>

           <meta-data/>

       </provider>

       <uses-library/>

    </application>

    <uses-permission/>

    <permission/>

    <permission-tree/>

    <permission-group/>

    <instrumentation/>

    <uses-sdk/>

    <uses-configuration/> 

    <uses-feature/> 

    <supports-screens/>

</manifest>