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學無止境

添加依賴
RxBinding庫是根據其所支持控件在Android平臺的位置而單獨分離的。

//Platform bindings:
compile 'com.jakewharton.rxbinding2:rxbinding:2.0.0'

//'support-v4' library bindings:
compile 'com.jakewharton.rxbinding2:rxbinding-support-v4:2.0.0'

//'appcompat-v7' library bindings:
compile 'com.jakewharton.rxbinding2:rxbinding-appcompat-v7:2.0.0'

//'design' library bindings:
compile 'com.jakewharton.rxbinding2:rxbinding-design:2.0.0'

//'recyclerview-v7' library bindings:
compile 'com.jakewharton.rxbinding2:rxbinding-recyclerview-v7:2.0.0'

//'leanback-v17' library bindings:
compile 'com.jakewharton.rxbinding2:rxbinding-leanback-v17:2.0.0'

應用示例：

按鈕的長按 / 點擊時間監聽

        RxView.longClicks(mButton)//長按
//                .clicks(mButton)//點擊
                .subscribe(new Consumer<Object>() {
                    @Override
                    public void accept(Object o) throws Exception {
                        Log.d("flag", "長按點擊了！");
                    }
                });

Button 防抖處理

        RxView.clicks(mButton)
                //兩秒鐘之內只取第一個點擊事件，防抖操作
                .throttleFirst(2, TimeUnit.SECONDS)
                .subscribe(new Consumer<Object>() {
                    @Override
                    public void accept(Object o) throws Exception {
                        Log.d("flag", "點擊了！");
                    }
                });

實現原理
以RxView.clicks()為例，clicks()源碼如下所示，

  @CheckResult @NonNull
  public static Observable<Object> clicks(@NonNull View view) {
    checkNotNull(view, "view == null");
    return new ViewClickObservable(view);
  }

返回一個ViewClickObservable對象，參數是傳入的view，然后來學習一下ViewClickObservable這個類，

final class ViewClickObservable extends Observable<Object> {
  private final View view;

  ViewClickObservable(View view) {
    this.view = view;
  }

  @Override protected void subscribeActual(Observer<? super Object> observer) {
    if (!checkMainThread(observer)) {
      return;
    }
    Listener listener = new Listener(view, observer);
    observer.onSubscribe(listener);
    view.setOnClickListener(listener);
  }

  static final class Listener extends MainThreadDisposable implements OnClickListener {
    private final View view;
    private final Observer<? super Object> observer;

    Listener(View view, Observer<? super Object> observer) {
      this.view = view;
      this.observer = observer;
    }

    @Override public void onClick(View v) {
      if (!isDisposed()) {
        observer.onNext(Notification.INSTANCE);
      }
    }

    @Override protected void onDispose() {
      view.setOnClickListener(null);
    }
  }
}

首先看是Listener這個類，它繼承了MainThreadDisposable并且實現了OnClickListener，在onClick()中訂閱者對這個事件進行了回調。同時onDispose()中停止對view的監聽；
而真正的訂閱發生在在subscribeActual()中，listener訂閱了上游的observer，并且設置了view的監聽事件；

除此之外，textChanges()，longClicks()也是類似這樣進一步的封裝；

對于RxJava的學習才剛剛開始！
RxJava：RxBus事件總線
RxJava：RxBinding
RxJava：Rxlifecycle