Best way to implement View.OnClickListener in android

Question

Suppose we have an Activity with a lot of views on which OnClickListener is to be registered.

The most common way to implement this is to let the Activi

Answer 1

simply you using like not implements subclass or not handle a click event just do like this way .

android.view.View.OnClickListener method_name = new android.view.View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            // put your code .
        }
    };

and handle click event into button ya any type of click event like

button_name.setOnClickListener(method_name);

its work very simply Thanks

Answer 2

I have found using Butterknife makes for clean code. And because it uses code generation (not reflections) it has little performance overhead.

public class ActivityMain extends Activity {

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

  @OnClick(R.id.button_foo)
  void onFoodClicked() {
    // Do some foo
  }

  @OnClick(R.id.button_bar)
  void onBarClicked() {
    // do some bar
  }
}

Answer 3

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Chronometer chronometer;
    private Button startButton;
    private Button stopButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        chronometer = findViewById(R.id.chronometer);
        startButton =findViewById(R.id.startBtn);
        stopButton = findViewById(R.id.stopBtn);

        startButton.setOnClickListener(this);
        stopButton.setOnClickListener(this);

    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.startBtn:
                chronometer.start();
                break;
            case R.id.stopBtn:`
                chronometer.stop();
                break;

        }
    }

}

Answer 4

Your ClickListener is an inner non-static class the coupling of this 'has-a' is no different than if your class Activity implemented View.OnClickListener. This is because your inner ClickListener requires an instance of ActivityMain and really can't be reused. I would argue that you're over engineering and aren't actually gaining anything.

EDIT: To answer your question I like to have anonymous View.OnClickListener for each widget. I think this creates the best separation of logic. I also have methods like setupHelloWorldTextView(TextView helloWorldTextView); where I put all my logic related to that widget.

Answer 5

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
Button north,south,east,west;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    init();
    north.setOnClickListener(this);
    south.setOnClickListener(this);
    east.setOnClickListener(this);
    west.setOnClickListener(this);
}

private void init(){
    north = findViewById(R.id.north);
    south = findViewById(R.id.south);
    east = findViewById(R.id.east);
    west = findViewById(R.id.west);
}

@Override
public void onClick(View v) {
    switch (v.getId()) {
        case R.id.north:
            Toast.makeText(MainActivity.this,"NORTH",Toast.LENGTH_SHORT).show();
            break;
        case R.id.south:
            Toast.makeText(MainActivity.this,"SOUTH",Toast.LENGTH_SHORT).show();
            break;
        case R.id.east:
            Toast.makeText(MainActivity.this,"EAST",Toast.LENGTH_SHORT).show();
            break;
        case R.id.west:
            Toast.makeText(MainActivity.this,"WEST",Toast.LENGTH_SHORT).show();
            break;
    }
  }
}

Answer 6

Here you can create a btnClickListner object and after that you will call that btnCLickLisner object when ever you want to perform the onCLieck actions for buttons..

Let us assume, in my activity i have a 5 to 10 buttons and writing each button separate onclick listner is bad idea. So to over come this,we can use like below..

register your buttons

Button button1 = (Button)findViewById(R.id.button1);
Button button2 = (Button)findViewById(R.id.button2);
Button button3 = (Button)findViewById(R.id.button3);
Button button4 = (Button)findViewById(R.id.button4);
Button button5 = (Button)findViewById(R.id.button5);

Here i am setting the onclick listner to my buttons after click

button1.setOnClickListener(btnClickListner);
button2.setOnClickListener(btnClickListner);
button3.setOnClickListener(btnClickListner);
button4.setOnClickListener(btnClickListner);
button5.setOnClickListener(btnClickListner);

Here is the btnClick Listner implementation

View.OnClickListener btnClickListner = new OnClickListener()
    {
  @Override
        public void onClick( View v )
        {
            // TODO Auto-generated method stub
            if( button1.getId() == v.getId() )
            {
                //Do Button1 click operations here

            }
            else if( button2.getId() == v.getId() )
            {

               // Do Button2 click operations here

            }
            else if( button3.getId() == v.getId() )
            {
                 // Do Button3 click operations here

            }
            else if( button4.getId() == v.getId() )
            {
                // Do Button4 click operations here

            }
            else if( button5.getId() == v.getId() )
            {
                // Do Button5 click operations here
            }

        }

     }