跨应用使用Service

从AnotherApp启动App的Service：
首先，在App中创建AppService：
public class AppService extends Service {
public AppService() {
}

@Override
public IBinder onBind(Intent intent) {
    // TODO: Return the communication channel to the service.
    throw new UnsupportedOperationException("Not yet implemented");
}

@Override
public void onCreate() {
    super.onCreate();
    System.out.println("Service start");
}

@Override
public void onDestroy() {
    super.onDestroy();
    System.out.println("service destroyed");
}

}
之后在AnotherApp里面启动App里面的AppService：
public class MainActivity extends AppCompatActivity implements View.OnClickListener {

private Intent serviceIntent;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    serviceIntent = new Intent();
    serviceIntent.setComponent(new ComponentName("com.chenshipeng.startservicefromanotherapp","com.chenshipeng.startservicefromanotherapp.AppService"));

    findViewById(R.id.btnStartAppService).setOnClickListener(this);
    findViewById(R.id.btnStopAppService).setOnClickListener(this);
}

@Override
public void onClick(View v) {
    switch (v.getId()){
        case R.id.btnStartAppService:
            startService(serviceIntent);
            break;
        case R.id.btnStopAppService:
            stopService(serviceIntent);
            break;
    }
}

}
这里的Intent通过设置组件名字，使用包名和服务的名字，来创建一个显示的Intent，这样就可以用来启动另外一个App的服务了。