Android中的服务（service）详解（二）--本地服务举例

野性酷女 2023-10-16 20:56 92阅读 0赞

**1. 引言：**

上篇已经将服务进行了分类， 从本篇开始，将对每种类型的服务给出一个实例。

本篇主要实例： 应用服务之**本地服务**的开启和运用。

这种服务的特点在上篇已进行了说明，它与App处于同一个进程，关于更多 的关于这种服务的说明,这里不再叙述。

下面，进行举例：

**2. 例子说明：**  
 （1）. 功能： 创建service，在service中查找指定的apk（用包名进行遍历匹配），如果找到，通过handler传递给UI，在UI中显示这些包名。

（2）. 您将学到：

**a. service中handler的运用；**

**b. 通过接口的方式回传到UI层。  
c. Service的定义和运用。**  
  
  
  
  
**3. 例子代码：  
（1）. PackageFindService：**  
package com.example.androidservicetest;  
  
  
import java.util.List;  
  
  
import android.app.Service;  
import android.content.Intent;  
  
  
import android.content.pm.PackageInfo;  
import android.os.Binder;  
import android.os.Handler;  
import android.os.IBinder;  
import android.os.Message;  
import android.util.Log;  
  
  
public class PackageFindService extends Service \{  
  
private static String\[\] pkgs = new String\[\] \{"com.tencent.mm","com.tencent.mobileqq",  
 "com.tencent.qqmusic",  
 "com.sina.weibo"  
\};  
  
private PackageFindListener mPackageFindListener;  
  
  
  
public class LocalBinder extends Binder \{  
public PackageFindService getService() \{  
Log.i("TAG", "getService ---> " + PackageFindService.this);  
return PackageFindService.this;  
\}  
\}  
  
  
@Override  
public IBinder onBind(Intent intent) \{  
Log.i("TAG", "onBind======================");  
return new LocalBinder();  
  
  
\}  
  
  
@Override  
public void onCreate() \{  
super.onCreate();  
Log.i("TAG", "onCreate======================");  
\}  
  
  
  
  
@Override  
public void onDestroy() \{  
// TODO Auto-generated method stub  
super.onDestroy();  
Log.i("TAG", "onDestroy======================");  
\}  
  
  
@Override  
public void onStart(Intent intent, int startId) \{  
super.onStart(intent, startId);  
Log.i("TAG", "onStart======================");  
\}  
  
  
@Override  
public int onStartCommand(Intent intent, int flags, int startId) \{  
Log.i("TAG", "onStartCommand======================");  
return super.onStartCommand(intent, flags, startId);  
\}  
  
  
@Override  
public boolean onUnbind(Intent intent) \{  
// TODO Auto-generated method stub  
Log.i("TAG", "onUnbind======================");  
return super.onUnbind(intent);  
\}  
  
/\*\*  
\* Find主函数  
\*/  
private void FindPackages() \{  
  
  
List<PackageInfo> list = this.getPackageManager().getInstalledPackages(0);  
if (list == null || list.size() < 1) \{  
return ;  
\}  
  
for (PackageInfo pkInfo : list) \{  
// 去掉本应用  
if (pkInfo.applicationInfo.packageName.equals(this.getPackageName())) \{  
continue;  
\}  
for (int i = 0; i<pkgs.length; i++) \{  
 if (pkInfo.applicationInfo.packageName.contains(pkgs\[i\])) \{  
 Message msg = new Message();  
 msg.what = 1;  
 msg.getData().putString("name", pkInfo.applicationInfo.packageName);  
  
  
 MyHandler.sendMessage(msg);  
//mPackageFindListener.onFindResult(true, pkInfo.applicationInfo.packageName); // **一定得用handler的方式通知listerner,，而这个liserner其实是为显示UI用的**。  
\}  
  
  
\}  
  
\}  
\}  
  
  
// find thread  
public void startFindThread()\{  
new Thread(new Runnable() \{  
@Override  
public void run() \{  
 FindPackages();  
 //find 完成后，由listener进行unbind  
 Message msg = new Message();  
 msg.what = 2;  
  
  
 MyHandler.sendMessage(msg);  
\}  
\}).start();  
\}  
  
**Handler** MyHandler = new Handler() \{  
public void handleMessage(Message msg) \{  
  
int what = msg.what;  
if (msg.what == 1) \{  
String pakName = msg.getData().getString("name");  
 **mPackageFindListener.onFindResult(true, pakName);**  
\} else \{  
mPackageFindListener.onFindResult(false, null);  
\}  
\};  
\};  
  
  
/\*\*  
\* 注册回调接口的方法，供外部调用  
\*/  
  
public void setListener(PackageFindListener listener) \{  
this.mPackageFindListener = listener;  
  
\}  
  
  
\}  
  
  
**（2）. PackageFindListener:**  
package com.example.androidservicetest;  
  
  
public interface PackageFindListener \{  
public void onFindResult(boolean isFind, String pkgName);  
  
  
\}  
  
  
  
  
**(3). MainActivity:**  
package com.example.androidservicetest;  
  
  
import android.os.Bundle;  
import android.os.IBinder;  
import android.app.Activity;  
import android.content.ComponentName;  
import android.content.Context;  
import android.content.Intent;  
import android.content.ServiceConnection;  
import android.util.Log;  
import android.view.Menu;  
import android.widget.TextView;  
  
  
public class MainActivity extends Activity \{  
private static String TAG = "MainActivity";  
  
private TextView textView;  
private String textStr = "";  
  
private PackageFindService mPackageFindService;  
private ServiceConnection conn;  
private Context mContext;  
  
  
  
@Override  
protected void onCreate(Bundle savedInstanceState) \{  
super.onCreate(savedInstanceState);  
setContentView(R.layout.activity\_main);  
textView = (TextView)findViewById(R.id.textview);  
textView.setText("Find:");  
  
mContext = this;  
  
startFindService();  
  
\}  
  
  
@Override  
public boolean onCreateOptionsMenu(Menu menu) \{  
// Inflate the menu; this adds items to the action bar if it is present.  
getMenuInflater().inflate(R.menu.main, menu);  
return true;  
\}  
  
private void startFindService() \{  
// 创建ServiceConnection  
  
conn = new ServiceConnection() \{  
  
  
@Override  
public void **onServiceConnected**(ComponentName arg0, IBinder service) \{  
Log.i(TAG, "onServiceConnected ====================begin");  
mPackageFindService = ((PackageFindService.LocalBinder) service)  
. **getService**();  
mPackageFindService. **setListener**(new PackageFindListener() \{  
  
  
@Override  
public void **onFindResult**(boolean isFind, String pkgName) \{  
if (isFind) \{  
textStr = textStr + pkgName + ";";  
textView.setText(textStr);  
\}else if (pkgName == null) \{  
mContext.unbindService(conn);  
\}  
\}  
\});  
  
 **if (mPackageFindService != null) \{  
mPackageFindService  
.startFindThread();**  
\}  
  
\}  
  
  
@Override  
public void onServiceDisconnected(ComponentName arg0) \{  
// TODO Auto-generated method stub  
  
\}  
  
\};  
  
// **绑定Service**  
Intent intent = new Intent("com.test.service");  
this.bindService(intent, conn, Context.BIND\_AUTO\_CREATE);  
  
  
\}  
  
内部类,也可以用这种方式进行listener的定义。  
// private PackageFindListener mPackageFindListener;  
// class MyPackageFindListener implements PackageFindListener \{  
//  
// @Override  
// public void onFindResult(boolean isFind, String pkgName) \{  
// if (isFind) \{  
// textStr = textStr + pkgName + ";";  
// textView.setText(textStr);  
// \}  
// \}  
//   
// \}  
  
  
\}  
  
  
**(4). AndroidManifest.xml:**  
<?xml version="1.0" encoding="utf-8"?>  
<manifest xmlns:android="http://schemas.android.com/apk/res/android"  
package="com.example.androidservicetest"  
android:versionCode="1"  
android:versionName="1.0" >  
  
  
<uses-sdk  
android:minSdkVersion="8"  
android:targetSdkVersion="18" />  
  
  
<application  
android:allowBackup="true"  
android:icon="@drawable/ic\_launcher"  
android:label="@string/app\_name"  
android:theme="@style/AppTheme" >  
<activity  
android:name="com.example.androidservicetest.MainActivity"  
android:label="@string/app\_name" >  
<intent-filter>  
<action android:name="android.intent.action.MAIN" />  
  
  
<category android:name="android.intent.category.LAUNCHER" />  
</intent-filter>  
</activity>  
  
<service android:name="com.example.androidservicetest.PackageFindService" >  
<intent-filter>  
<action android:name=" **com.test.service**"/>  
</intent-filter>  
</service>  
</application>  
  
  
</manifest>  
  
  
**4. 测试结果：  
运行程序后，在屏幕上将会显示：**

**com.sina.weibo；com.tencent.mm；com.tencent.mobileqq**；

**5. 实例代码下载（包含了远程服务测试实例）：**

**http://download.csdn.net/detail/liranke/8401933**