android动态换肤系列3——从apk文件中获取Resources对象（上）

1、新建一个空的工程x，只把本工程的res文件覆盖过去，然后利用这个x生成apk。改名为“text.thinking”，并放在跟目录下。

读取x的Resources对象过程如下：

ResourcesActivity.java文件

package com.thinking.skintest;

import java.io.File;

import java.lang.reflect.Method;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import com.thinking.skintest.Read.IListener;

import android.app.Activity;

import android.content.Context;

import android.content.pm.PackageInfo;

import android.content.pm.PackageManager;

import android.content.res.AssetManager;

import android.content.res.Configuration;

import android.content.res.Resources;

import android.os.Bundle;

import android.os.Environment;

import android.os.Handler;

import android.util.DisplayMetrics;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;

public class ResourcesActivity extends Activity implements IListener {

private Button btn_start;

private TextView txt_pk;

private TextView txt_res;

private Handler mHandler = new Handler();

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_resources);

btn_start = (Button) findViewById(R.id.btn_start);

txt_pk = (TextView) findViewById(R.id.txt_pk);

txt_res = (TextView) findViewById(R.id.txt_res);

btn_start.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View arg0) {

new Read().doRead(ResourcesActivity.this,

ResourcesActivity.this);

}

});

}

@Override

public void onReadPkName(final String pk_name) {

// TODO Auto-generated method stub

mHandler.post(new Runnable() {

@Override

public void run() {

txt_pk.setText(pk_name);

}

});

}

@Override

public void onReadRes(final int hash_code) {

mHandler.post(new Runnable() {

@Override

public void run() {

txt_res.setText(hash_code + "");

}

});

}

}

class Read {

public static ExecutorService pool = Executors.newFixedThreadPool(1);

private static String SDCardPath = Environment

.getExternalStorageDirectory().getPath();

public interface IListener {

public void onReadPkName(String pk_name);

public void onReadRes(int hash_code);

}

public void doRead(final Context context, final IListener listener) {

pool.execute(new Runnable() {

@Override

public void run() {

// 制作text.thinking压缩文件，文件目录与本apk相同

File file = new File(SDCardPath + "/" + "text.thinking");

// 获取text.thinking的packageName

PackageManager mPm = context.getPackageManager();

PackageInfo mInfo = mPm.getPackageArchiveInfo(

file.getAbsolutePath(), PackageManager.GET_ACTIVITIES);

String pk_name = mInfo.packageName;

listener.onReadPkName(pk_name);// 需要READ_EXTERNAL_STORAGE权限

// 通过反射获取text.thinking的参数

AssetManager assetManager = null;

try {

assetManager = AssetManager.class.newInstance();

Method addAssetPath = assetManager.getClass().getMethod(

"addAssetPath", String.class);

addAssetPath.invoke(assetManager, file.getAbsolutePath());

} catch (Exception e) {

e.printStackTrace();

}

// 用本地Resources的参数（屏幕、配置信息等）实例化

DisplayMetrics disp = context.getResources()

.getDisplayMetrics();

Configuration config = context.getResources()

.getConfiguration();

Resources newResource = new Resources(assetManager, disp,

config);

listener.onReadRes(newResource.hashCode());

}

});

}

}

activity_resources.xml文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="vertical" >

<Button

android:id="@+id/btn_start"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:text="Start" />

<TextView

android:id="@+id/txt_pk"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:textSize="12sp" />

<TextView

android:id="@+id/txt_res"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:textSize="12sp" />

</LinearLayout>

运行结果