在AIDL文件里面添加方法：
void setData(String data);
使用的时候需要实现这个接口，
public class AppService extends Service {
public AppService() {
}

@Override
public IBinder onBind(Intent intent) {
  
    return new IAppServiceRemoteBindler.Stub() {
        @Override
        public void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat, double aDouble, String aString) throws RemoteException {

        }

        @Override
        public void setData(String data) throws RemoteException {

            AppService.this.data = data;
        }
    };
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    return super.onStartCommand(intent, flags, startId);
}

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

    new Thread(){
        @Override
        public void run() {
            super.run();
            running = true;
            while (running){
                System.out.println(data);
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    }.start();
}

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

    running = false;
}

private String data = "默认数据";

private boolean running = false;

}
要想通过Binder去执行另外一个App里面AIDL的函数，需要把App里面的AIDL文件拷贝到AnotherApp中，并且包名要和App中一样（先创建一个AIDL的folder，然后创建一个包，包名和App里面AIDL包名字一样，然后在创建一个一样的AIDL文件）。
之后就可以在AnotherApp中使用这个AIDL，以及里面的方法：
public class MainActivity extends AppCompatActivity implements View.OnClickListener, ServiceConnection {

private Intent serviceIntent;
private EditText etInput;
@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"));

    etInput = (EditText)findViewById(R.id.etInput);

    findViewById(R.id.btnStartAppService).setOnClickListener(this);
    findViewById(R.id.btnStopAppService).setOnClickListener(this);
    findViewById(R.id.bindAppService).setOnClickListener(this);
    findViewById(R.id.unBindAppService).setOnClickListener(this);
    findViewById(R.id.btnSync).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;
        case R.id.bindAppService:
            bindService(serviceIntent,this, Context.BIND_AUTO_CREATE);
            break;
        case R.id.unBindAppService:
            unbindService(this);
            bindler = null;
            break;
        case R.id.btnSync:
            if (bindler != null){

                try {
                    bindler.setData(etInput.getText().toString());
                } catch (RemoteException e) {
                    e.printStackTrace();
                }

            }
            break;
    }
}

@Override
public void onServiceConnected(ComponentName name, IBinder service) {

    System.out.println("bind service");
    System.out.println(service);
       //这里不能直接进行强制类型转换，虽然名字一样，但是是在两个App钟，内存地址是不一样的，所以用以下这种转换方式。
    bindler = IAppServiceRemoteBindler.Stub.asInterface(service);
}

@Override
public void onServiceDisconnected(ComponentName name) {

}
private IAppServiceRemoteBindler bindler = null;

}