.java

public class ViewModelDemoActivity extends LifecycleActivity {

    @BindView(R.id.click_count_text)
    protected TextView clickCountText;

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

    @OnClick(R.id.increment_button)
    public void incrementClickCount(View button) {
      int currentClickCount = Integer.parseInt(clickCountText.getText().toString());
      clickCountText.setText(String.valueOf(++currentClickCount));
    }
}