android怎么声明多个包

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"      package="Dirs.Activity"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk android:minSdkVersion="4" />                <!-- android 版本支持 -->        <supports-screens android:largeScreens="true"             android:normalScreens="true" android:smallScreens="true"            android:resizeable="true" android:anyDensity="true"/>        <uses-sdk android:minSdkVersion="3"></uses-sdk>    <!-- android 版本支持 -->                    <application        android:icon="@drawable/ic_launcher"        android:label="@string/app_name" >        <activity             android:name=".Welcome"            android:label="@string/app_name" >                       <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>               <activity            android:name=".Main"            android:label="@string/app_name" >        </activity>               <activity android:name=".Dirs.map.BaiduMap"></activity>    </application>        <!-- BaiduMap使用权限 -->            <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>            <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>            <uses-permission android:name="android.permission.INTERNET"></uses-permission>            <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>            <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>              <uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission>             <uses-permission android:name="android.permission.READ_PHONE_STATE"></uses-permission>        <!-- BaiduMap使用权限 -->        </manifest>