OnClickMethod-Android

AwesomeButtonActivity_2.java

public class AwesomeButtonActivity extends AppCompatActivity {

    private Button awesomeButton;
    
    private View.OnClickListener awesomeOnClickListener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            awesomeButtonClicked();
        }
    };

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        awesomeButton = new Button(this);

        awesomeButton.setOnClickListener(awesomeOnClickListener);
    }

    private void awesomeButtonClicked() {
        awesomeButton.setText("AWESOME!");
    }
}

One reason why I like this option is it is incredibly easy to refactor option one into option two. All you have to do is take your implementation and move it out of setOnClickListener, assign it to a field, and then update your call to setOnClickListener to reference that field.

Another reason why I like this option is it allows you to reuse the implementation. So when one of our customers demands that we add a second button that does the exact same thing as our OG awesome button, all we have to do is call setOnClickListener and pass in the field.

The last reason I wanted to bring up is this creates a seam that will allow us to test this class easier. In the example above we can use Powermock’s Whitebox Class to replace the field with a mock or stub of OnClickListener.

Oh, another positive to this route is it can help you organize your code a bit better as well.