public class BaseActivity extends AppCompatActivity {

  Subscription mSubscription;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Utils.intiSySBar(this, R.color.colorblack);
    initRxBus();
  }

  //接收退出的指令，关闭所有activity
  private void initRxBus() {
    mSubscription = RxBus.getInstance().toObserverable(NormalEvent.class)
        .subscribe(new Action1<NormalEvent>() {
                @Override
                public void call(NormalEvent userEvent) {
                  if (userEvent.getType() == -1) {
                    finish();
                  }
                }
              },
            new Action1<Throwable>() {
              @Override
              public void call(Throwable throwable) {
              }
            });
  }

  @Override
  protected void onDestroy() {
    super.onDestroy();
    if (!mSubscription.isUnsubscribed()) {
      mSubscription.unsubscribe();
    }
  }
}

public class NormalEvent {
  private int type;

  public NormalEvent(int type) {
    this.type = type;
  }

  public int getType() {
    return type;
  }

  public void setType(int type) {
    this.type = type;
  }
}

 RxBus.getInstance().post(new NormalEvent(-1));//发送退出指令