Click listener with Binding

public interface ClickHandler {
    public void onButtonClick(View v);
}

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">

    <data>
        <variable
            name="handler"
            type="com.example.ClickHandler"/>
    </data>

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="click me"
            android:onClick="@{handler.onButtonClick}"/>
    </RelativeLayout>
</layout>

public class MainActivity extends Activity implements ClickHandler {

    private ActivityMainBinding binding;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = DataBindingUtil.setContentView(this,R.layout.activity_main);
        binding.setHandler(this);
    }

    @Override
    public void onButtonClick(View v) {
        Toast.makeText(context,"Button clicked",Toast.LENGTH_LONG).show();
    }
}