Data binding: Not call onClick method - android-databinding

Question

Android 4.3+
I trt to use data binding. I use official documentation from here Data binding
So in app/build.gradle:
dataBinding {
enabled = true
}
In my xml layout file:
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<data>
<variable
name="handler"
type="com.myproject.SettingsFragment" />
</data>
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent" >
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.constraint.ConstraintLayout
android:id="#+id/contentContainer"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.constraint.ConstraintLayout
android:id="#+id/contactUsContainer"
android:layout_width="match_parent"
android:onClick="#{handler::onClickContactUs}">
<TextView
android:id="#+id/contactUsTextView"
android:layout_width="0dp"
android:layout_height="wrap_content"/>
</android.support.constraint.ConstraintLayout>
</android.support.constraint.ConstraintLayout>
</FrameLayout>
</ScrollView>
</android.support.constraint.ConstraintLayout>
</layout>
And here my fragment SettingsFragment.java:
public class SettingsFragment extends Fragment {
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.settings, container, false);
return rootView;
}
public void onClickContactUs(View view) {
}
}
But when I click on container contactUsContainer the method onClickContactUs() is NOT call.
Why?

Answer 1

You're experiencing a common problem. First, you must inflate the binding using the binding inflate() call. Second, you must set the binding variables:
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
MyLayoutBinding binding = MyLayoutBinding.inflate(inflater, container, false);
binding.setHandler(this);
return binding.getRoot();
}

Answer 2

#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
userDetailViewBinding=DataBindingUtil.inflate(inflater,R.layout.fragment_user_detail_view, container, false);
ProfileViewModel.Factory factory = new ProfileViewModel.Factory(getActivity().getApplication());
viewModel = ViewModelProviders.of(this, factory)
.get(ProfileViewModel.class);
observeViewModel(viewModel);
userDetailViewBinding.setProfileViewModel(viewModel);
userDetailViewBinding.setUserDetailViewFrag(this);
return userDetailViewBinding.getRoot();
}