dark_ruby dark_ruby - 5 months ago 30
Android Question

How to use data-binding with Fragment

I'm trying to follow data-binding example from official google doc https://developer.android.com/tools/data-binding/guide.html

except that I'm trying to apply data-biding to a fragment, not an activity.

the error I'm currently getting when compiling is

Error:(37, 27) No resource type specified (at 'text' with value '@{marsdata.martianSols}.


onCreate
for fragment looks like this:

@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MartianDataBinding binding = MartianDataBinding.inflate(getActivity().getLayoutInflater());
binding.setMarsdata(this);
}


onCreateView
for fragment looks like this:

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.martian_data, container, false);
}


and parts of my layout file for fragment looks like this:

<?xml version="1.0" encoding="utf-8"?>

<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<variable
name="marsdata"
type="uk.co.darkruby.app.myapp.MarsDataProvider" />
</data>
...

<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="@{marsdata.martianSols}"
/>

</RelativeLayout>
</layout>


my suspicion is that
MartianDataBinding
doesn't know which layout file it's supposed to be bound with - hence the error. Any suggestions?

Answer

@dark_ruby The data binding implementation must be in the onCreateView method of the fragment , delete any data Binding that exist in your OnCreate method , your onCreateView should look like this :

public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
MartianDataBinding binding = DataBindingUtil.inflate(inflater, R.layout.martian_data, container, false);
        View view = binding.getRoot();
//here data must be an instance of the class MarsDataProvider
binding.setMarsdata(data);
return view;
}