如何在Android中注册多个侦听器？

Question

In iOS I can register multiple target+action event handlers for eg a button like this:

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(20, 40, 300, 40)];
    [button setBackgroundColor:[UIColor blueColor]];
    [button setTitle:@"Click Me!" forState:UIControlStateNormal];
    [button addTarget:self action:@selector(handler1) forControlEvents:UIControlEventTouchUpInside];
    [button addTarget:self action:@selector(handler2) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button];
}

- (void)handler1 {
    NSLog(@"Click handler 1"); // FIRES!
}

- (void)handler2 {
    NSLog(@"Click handler 2"); // FIRES!
}

@end

I want to achieve something similar in Java/Android, unfortunately this won't work so far as the first listener gets replaced by the second:

public class MainActivity extends AppCompatActivity {

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

    Button button = (Button) findViewById(R.id.button);
    button.setText("Click Me!");
    button.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        Log.d("Test", "Click handler 1"); // DOES NOT FIRE!
      }
    });
    button.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        Log.d("Test", "Click handler 2"); // FIRES!
      }
    });

  }
}

I appreciate any help & suggestions to achieve the same in Java/Android!

Answer 1

Read about RxJava it is the future :) http://reactivex.io/

ViewObservable.clicks((Button) getActivity().findViewById(R.id.comment_btn))
            .compose(lifecycleMainObservable().<OnClickEvent>bindLifecycle())
            .subscribe(new Action1<OnClickEvent>() {
                @Override
                public void call(OnClickEvent onClickEvent) {
                    Log.d("Button click", "Button 1 click");
                }
            });

ViewObservable.clicks((Button) getActivity().findViewById(R.id.comment_btn))
            .compose(lifecycleMainObservable().<OnClickEvent>bindLifecycle())
            .subscribe(new Action1<OnClickEvent>() {
                @Override
                public void call(OnClickEvent onClickEvent) {
                    Log.d("Button click", "Button 2 click");
                }
            });

Answer 2

Is it not handled the same way in Android and it is just simpler to create two methods as such:

button.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        method1();
        method2();
      }
    });

   private void method1(){
     Log.d("Test", "Click handler 1");
   }

   private void method2(){
     Log.d("Test", "Click handler 2");
   }

As the docs for View.OnClickListener state:

Register a callback to be invoked when this view is context clicked. If the view is not context clickable, it becomes context clickable

Multiple callbacks are not implemented by default, but you could implement it yourself.