Android学习之Service(1)--->Started方式
界面退出后进程程序还在运行,不会被杀死,如音乐播发器、后台下载等
注:本文只讨论Started方式
main.xml代码分析
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <Button android:id="@+id/btnStartService" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Start Service" /> <Button android:id="@+id/btnStopService" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Stop Service" /> </LinearLayout>
创建一个class类ExampleService.java
package com.szy.service; import android.app.Service; import android.content.Intent; import android.os.IBinder; import android.util.Log; public class ExampleService extends Service { private static final String TAG="ExampleService"; @Override public void onCreate() { Log.i(TAG, "ExampleService-->onCreate"); super.onCreate(); } @Override public void onStart(Intent intent, int startId) { // TODO Auto-generated method stub super.onStart(intent, startId); } @Override public void onDestroy() { Log.i(TAG, "ExampleService-->onDestroy"); super.onDestroy(); } @Override public int onStartCommand(Intent intent, int flags, int startId) { Log.i(TAG, "ExampleService-->onStartCommand"); return START_NOT_STICKY; } @Override public IBinder onBind(Intent intent) { return null; } }
主对象类MainActivity.java
package com.szy.service; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class MainActivity extends Activity { private Button btnStartService; private Button btnStopService; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); btnStartService = (Button) findViewById(R.id.btnStartService); btnStopService = (Button) findViewById(R.id.btnStopService); btnStartService.setOnClickListener(listener); btnStopService.setOnClickListener(listener); } private OnClickListener listener=new OnClickListener() { public void onClick(View v) { Intent intent=new Intent(MainActivity.this, ExampleService.class); switch (v.getId()) { case R.id.btnStartService: startService(intent); break; case R.id.btnStopService: stopService(intent); break; default: break; } } }; }
在AndroidManifest.xml定义一下
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.szy.service" android:versionCode="1" android:versionName="1.0"> <uses-sdk android:minSdkVersion="8" /> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".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=".ExampleService" /> </application> </manifest>