1、要使用Service,首先就是在配置文件里吗添加Service,如果不填加,你的Service是不能够使用的。目前学到的方法有两种
方法一:<service android:enabled="true" android:name=".PlayService" />
方法二:<service android:name=".PlayService" />
点后面是Service类的名字。
2、工程包括两个类:
ServiceActivity.java
PlayService.java
其中:ServiceActivity.java定义了两个按钮,分别控制音乐的播放与停止。
用startService和stopService完成Activity与Service之间的切换,启动Service以及取消Service,
如果不用按钮,可以在Activity的OnCreate和OnDestrpy里面启动和取消Service,如下:
buttonOn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
startService(new Intent(MainActivity.this,PlayService.class));
}
});
buttonOff.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
stopService(new Intent(MainActivity.this,PlayService.class));
//stopService(new Intent(this, PlayService.class));
}
});
PlayService,java
public class PlayService extends Service {
MediaPlayer mediaPlayer;
String TAG = "main";
@Nullable
@Override
public IBinder onBind(Intent intent) {
Log.e("main","onbind");
return null;
}
@Override
public void onCreate() {
super.onCreate();
Toast.makeText(this, "Play Service Created", Toast.LENGTH_LONG).show();
Log.e(TAG, "ServiceonCreate");
mediaPlayer = MediaPlayer.create(this, R.raw.aaa);
}
@Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
Toast.makeText(this, "Play Service onStart", Toast.LENGTH_LONG).show();
Log.e(TAG, "ServiceonStart");
mediaPlayer.start();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.e(TAG, "onStartCommand");
return super.onStartCommand(intent, flags, startId);
}
@Override
public void onDestroy() {
super.onDestroy();
Toast.makeText(this, "Play Service Stopped", Toast.LENGTH_LONG).show();
Log.e(TAG, "ServiconDestroy");
mediaPlayer.stop();
}
}
输出结果:
12-15 06:00:40.908 4396-4396/com.example.myapplication E/main: ServiceonCreate
12-15 06:00:40.919 4396-4396/com.example.myapplication E/main: onStartCommand
12-15 06:00:40.922 4396-4396/com.example.myapplication E/main: ServiceonStart
12-15 06:00:44.532 4396-4396/com.example.myapplication E/main: ServiconDestroy
12-15 06:00:48.503 4396-4396/com.example.myapplication E/main: onpause
12-15 06:00:49.173 4396-4396/com.example.myapplication E/main: onstop
12-15 06:00:49.173 4396-4396/com.example.myapplication E/main: ondestroy