《Android进阶之光》--RxJava实现RxBus

事件总线RxBus，替代EventBus和otto

1）创建RxBus

public class RxBus{
    private static volatile RxBus rxBus;
    private final Subject<Object,Object> subject = new SerializedSubject<>(PublishSubject.create());
    private RxBus(){
    }
    public static RxBus getInstance(){
        if(rxBus == null){
            synchronized(RxBus.class){
                if(rxBus == null){
                    rxBus = new RxBus();
                }
            }
        }
        return rxBus;
    }
    public void post(Object ob){
        subject.onNext(ob);
    }
    public <T> Observalbe<T> toObservable(Class<T> eventType){
        return subject.ofType(eventType);
    }
}

public final <R> Observable<R> ofType(final Class<R> klass){
    return filter(InternalObservableUtils.isInstanceOf(klass)).cast(klass);
}

2）发送事件

public class RxBusActivity extends AppComaptActivity{
    private Button bt_post;
    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_rx_bus);
        bt_post = (Button)this.findViewById(R.id.bt_post);
        bt_post.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v){
                RxBus.getInstance().post(new MessageEvent("用RxJava实现RxBus"));
            }
        });
    }
}

3）接收事件

public class RxBusFragment extends Fragment{
    ...
    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState){
        super.onActivityCreated(savedInstanceState);
        subscription = RxBus.getInstance().toObservable(MessageEvent.class).subscribe(new Action1<MessageEvent>(){
            @Override
            public void call(MessageEvent messageEvent){
                if(messageEvent!=null){
                    tv_text.setText(messageEvent.getMessage());
                }
            }
        });
    }
}

4）取消订阅事件

@Override
public void onDestroy(){
    super.onDestroy();
    if(subscription!=null&&!subscription.isUnsubscribed()){
        subscription.unsubscribe();
    }
}