学步园

原理：主程序与主题apk使用相同的sharedUserId, 使得主程序可以访问主题apk包中的资源

主程序：MainSkin.apk

主题包：SkinTest1.apk, SkinTest2.apk

MainSkin实现一个activity来加载SkinTest1或SkinTest2中的资源，给自己设置不同主题的背景图片和按钮图片

MainSkin的AndroidManifest.xml如下：

<?xml version="1.0" encoding="utf-8"?><br /> <manifest xmlns:android="http://schemas.android.com/apk/res/android"<br /> package="com.huyuke.mainskin"<br /> android:sharedUserId="com.huyuke.mainskin"><br /> <application<br /> android:label="@string/app_name"<br /> android:launchMode="singleInstance"<br /> android:debuggable="true"<br /> android:allowTaskReparenting="true"><br /> <activity android:name="MainSkinActivity"><br /> <intent-filter><br /> <action android:name="android.intent.action.MAIN"/><br /> <category android:name="android.intent.category.LAUNCHER"/><br /> </intent-filter><br /> </activity><br /> <receiver android:name="SkinPackagesManager"><br /> <intent-filter><br /> <action android:name="android.intent.action.PACKAGE_ADDED" /><br /> <action android:name="android.intent.action.PACKAGE_CHANGED" /><br /> <action android:name="android.intent.action.PACKAGE_DATA_CLEARED" /><br /> <action android:name="android.intent.action.PACKAGE_INSTALL" /><br /> <action android:name="android.intent.action.PACKAGE_REMOVED" /><br /> <action android:name="android.intent.action.PACKAGE_REPLACED" /><br /> <action android:name="android.intent.action.PACKAGE_RESTARTED" /><br /> <action android:name="android.intent.action.EXTERNAL_APPLICATIONS_AVAILABLE"/><br /> <action android:name="android.intent.action.EXTERNAL_APPLICATIONS_UNAVAILABLE"/><br /> <data android:scheme="package"/><br /> </intent-filter><br /> </receiver><br /> </application><br /> </manifest><br />

MainSkin的Acitivity定义：

package com.huyuke.mainskin;<br /> import android.app.Activity;<br /> import android.content.Context;<br /> import android.content.pm.PackageManager.NameNotFoundException;<br /> import android.content.pm.PackageInfo;<br /> import android.content.res.Resources;<br /> import android.os.Bundle;<br /> import android.os.Process;<br /> import android.widget.LinearLayout;<br /> import android.widget.Button;<br /> import android.view.View;<br /> import android.view.View.OnClickListener;<br /> import android.util.Log;<br /> import java.util.ArrayList;<br /> public class MainSkinActivity extends Activity implements OnClickListener {<br /> private static final String TAG = "MainSkinActivity";<br /> private LinearLayout mBg;<br /> private Button mBtn;<br /> private Resources defaultRes = null;<br /> private ArrayList<String> mSkinPkgs = new ArrayList<String>();<br /> private int mCurrSkinIndex = 0;<br /> @Override<br /> public void onCreate(Bundle savedInstanceState) {<br /> super.onCreate(savedInstanceState);<br /> setContentView(R.layout.main);<br /> setTitle(R.string.theme_name);<br /> mBg = (LinearLayout) findViewById(R.id.linear_layout_1);<br /> mBtn = (Button) findViewById(R.id.btn_change_skin);<br /> mBg.setBackgroundResource(R.drawable.bg);<br /> mBtn.setBackgroundResource(R.drawable.btn_normal);<br /> mBtn.setOnClickListener(this);<br /> getSkinPackages();<br /> }<br /> public void onClick(View v) {<br /> String skinPkgToSet= mSkinPkgs.get(mCurrSkinIndex);<br /> mCurrSkinIndex++;<br /> if (mCurrSkinIndex == mSkinPkgs.size()) {<br /> mCurrSkinIndex = 0;<br /> }<br /> applySkin(skinPkgToSet);<br /> }<br /> private void applySkin(String skinPkg){<br /> Context skinContext;<br /> try {<br /> skinContext = this.createPackageContext(skinPkg, Context.CONTEXT_IGNORE_SECURITY);<br /> } catch (NameNotFoundException e) {<br /> Log.e(TAG, "createPackageContext exception: " + e);<br /> e.printStackTrace();<br /> return;<br /> }<br /> Resources res = skinContext.getResources();<br /> /*<br /> OR<br /> try {<br /> res = getPackageManager().getResourcesForApplication(skinPkg);<br /> } catch (NameNotFoundException e) {<br /> Log.e(TAG, "getResourcesForApplication exception: " + e);<br /> return;<br /> }<br /> */<br /> mBg.setBackgroundDrawable(res.getDrawable(res.getIdentifier("bg", "drawable", skinPkg)));<br /> mBtn.setBackgroundDrawable(res.getDrawable(res.getIdentifier("btn_normal", "drawable", skinPkg)));<br /> setTitle(res.getString(res.getIdentifier("theme_name", "string", skinPkg)));<br /> }<br /> private void getSkinPackages() {<br /> String[] skinPkgs = getPackageManager().getPackagesForUid(Process.myUid());<br /> String self = getPackageName();<br /> for (String skinPackage: skinPkgs) {<br /> Log.i(TAG, "package for this user: " + skinPackage);<br /> if (!(self.equals(skinPackage))) {<br /> Log.i(TAG, "this is a skin package");<br /> mSkinPkgs.add(skinPackage);<br /> }<br /> }<br /> Log.i(TAG, "I have " + mSkinPkgs.size() + " skins");<br /> }<br /> }<br />

同时MainSkin中需要放一套默认图片资源

主题包中不需要代码，只需要资源文件和在manifest里面声明和主程序MainSkin使用相同的sharedUserId即可，

在这两个主题包中分别放了两套不同的图片，每套图包括一张activity背景图和一张button背景图

如SkinTest1的AndroidManifest.xml内容如下：

<?xml version="1.0" encoding="utf-8"?><br /> <manifest xmlns:android="http://schemas.android.com/apk/res/android"<br /> package="com.huyuke.skintest1"<br /> android:sharedUserId="com.huyuke.mainskin"><br /> </manifest> 

显示效果：