BaseActivity.java

public abstract class BaseActivity<P extends BasePresenter> extends AppCompatActivity
        implements BaseView {

    private Unbinder mUnBinder;

    private ProgressDialog mProgressDialog = null;

    protected @NonNull abstract P getPresenterInstance();

    protected P mPresenter;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mPresenter = getPresenterInstance();
        mPresenter.attachView(this);
    }

    @Override
    public void setContentView(@LayoutRes int layoutResID) {
        super.setContentView(layoutResID);
        mUnBinder = ButterKnife.bind(this);
    }

    @Override
    protected void onDestroy() {
        mPresenter.detachView();
        mUnBinder.unbind();
        super.onDestroy();
    }

    @Override
    public View getContentView() {
        return getWindow().getDecorView();
    }
}