Android中实现应用切换主题机制
一直很想弄清楚好多应用中是如何实现换皮肤这项功能的，花了下午点时间，查了下资料也实现了个切换主题的Demo;
首先要感谢下这位大哥,参阅了下他写的文件http://www.eoeandroid.com/forum-viewthread-tid-31756-highlight-%E7%9A%AE%E8%82%A4.html
好了，废话不多说了，该切换主题的demo里面一共实现了两个功能，其一，搜索已经安装的皮肤，其二，应用安装的皮肤。
主项目包名为org.leepood.skindemo,主题项目的包名为org.leepood.skin.blue,org.leepood.skin.red,等等，只要前缀是org.leepood.skin.就行。
首先是查找已安装主题的代码:
package org.leepood.skindemo;import java.util.ArrayList;import java.util.List;import android.app.Activity;import android.app.ProgressDialog;import android.content.Context;import android.content.Intent;import android.content.SharedPreferences;import android.content.pm.PackageInfo;import android.content.pm.PackageManager;import android.content.pm.PackageManager.NameNotFoundException;import android.content.res.Resources;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.view.ContextMenu;import android.view.LayoutInflater;import android.view.MenuItem;import android.view.View;import android.view.ViewGroup;import android.view.ContextMenu.ContextMenuInfo;import android.view.View.OnCreateContextMenuListener;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.ListView;import android.widget.TextView;import android.widget.Toast;import android.widget.AdapterView.AdapterContextMenuInfo;public class Main extends Activity implements SharedPreferences.OnSharedPreferenceChangeListener{private ListView listview;private Context c;private Handler mHandler;private ProgressDialog pDialog;private SkinAdapter adapter;private SharedPreferences sp;static final int MESSAGE_SEARCHED_SKIN=0;static final int MESSAGE_SEARCHING_SKIN=MESSAGE_SEARCHED_SKIN+1;static final int MESSAGE_SEARCHED_SKIN_FOR_NONTHING=MESSAGE_SEARCHING_SKIN+1;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);init();pDialog.show();new Thread(serachSkin).start();}private void init(){c=this;mHandler=new Handler(){@Overridepublic void handleMessage(Message msg) {switch(msg.what){case MESSAGE_SEARCHED_SKIN:ArrayList skins=(ArrayList) msg.obj;//获取skinsadapter=new SkinAdapter(c, skins);listview.setAdapter(adapter);Toast.makeText(c, "查找到已经安装的皮肤", 1).show();pDialog.dismiss();break;case MESSAGE_SEARCHED_SKIN_FOR_NONTHING:Toast.makeText(c, "未查找到任何皮肤", 1).show();pDialog.dismiss();}}};sp=this.getSharedPreferences("config",Context.MODE_WORLD_WRITEABLE);sp.registerOnSharedPreferenceChangeListener(this);listview=(ListView) findViewById(R.id.list);listview.setItemsCanFocus(false);listview.setChoiceMode(ListView.CHOICE_MODE_SINGLE);pDialog=new ProgressDialog(this);pDialog.setMessage("正在查找已经安装的皮肤");listview.setOnCreateContextMenuListener(new OnCreateContextMenuListener() {public void onCreateContextMenu(ContextMenu menu, View v,ContextMenuInfo menuInfo) {menu.add("使用该主题");}});}private Runnable serachSkin =new Runnable(){public void run() {PackageManager manager=c.getPackageManager();List packages=manager.getInstalledPackages(PackageManager.PERMISSION_GRANTED);ArrayList skins=new ArrayList();for(PackageInfo info:packages){//System.out.println(info.packageName);if(info.packageName.startsWith("org.leepood.skin.")){skins.add(info);}}if(skins.size()>0){Message msg=mHandler.obtainMessage();msg.obj=skins;msg.what=MESSAGE_SEARCHED_SKIN;mHandler.sendMessage(msg);}else{mHandler.sendEmptyMessage(MESSAGE_SEARCHED_SKIN_FOR_NONTHING);}}};private class SkinAdapter extends BaseAdapter{LayoutInflater mInflater;ArrayList datas;PackageManager manager;public SkinAdapter(Context c,ArrayList datas){this.datas=datas; mInflater=LayoutInflater.from(c); manager=c.getPackageManager();}public int getCount() {return datas.size();}public Object getItem(int position) {return datas.get(position);}public long getItemId(int position) {return 0;}public View getView(int position, View convertView, ViewGroup parent) {if(convertView==null){convertView=mInflater.inflate(R.layout.skin_item, null);}ImageView icon=(ImageView) convertView.findViewById(R.id.skin_icon);TextView skin_name=(TextView) convertView.findViewById(R.id.skin_name);PackageInfo info=datas.get(position);icon.setImageDrawable(info.applicationInfo.loadIcon(manager));skin_name.setText(info.applicationInfo.loadLabel(manager));return convertView;}}public void onThemeChanged(String newThemePackageName) {try {Context themeContext=this.createPackageContext(newThemePackageName, CONTEXT_IGNORE_SECURITY);Resources res=themeContext.getResources();setControlsStyle(res);} catch (NameNotFoundException e) {e.printStackTrace();}}private void setControlsStyle(Resources res){listview.setBackgroundColor(res.getColor(R.color.ListView_bg));}@Overridepublic boolean onContextItemSelected(MenuItem item) {AdapterContextMenuInfo menuInfo=(AdapterContextMenuInfo)item.getMenuInfo();PackageInfo info=(PackageInfo) adapter.getItem(menuInfo.position);sp.edit().putString("themePackage", info.packageName).commit();return super.onContextItemSelected(item);}public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,String key) {System.out.println("themeChange");onThemeChanged(sharedPreferences.getString(key, ""));}}