I have a problem that is driving me nuts and been searching several hours around the web but cant find a solution. I want to set an animation on the first view in my recyclerview when I add new data to the list. But I cant because the recyclerview is null.
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
orientation = getResources().getConfiguration().orientation;
model = ViewModelProviders.of(getActivity()).get(ViewModelAdvices.class);
model.getAdvices().observe(this, new Observer <List <Advice>>() {
//Update recyclerview automatically when data is changed
@Override
public void onChanged(List <Advice> advices) {
filtered_advices_list.clear();
filtered_advices_list.addAll(advices);
adapter_recycler_view.notifyDataSetChanged();
}
});
}
@Override
public void onResume() {
super.onResume();
Animation animation = AnimationUtils.loadAnimation(getContext(), R.anim.test_item);
View v = recycler_view.getChildAt(0);
v.startAnimation(animation);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.show_advices_fragment, container, false);
setupLayoutDifferences(view);
recycler_view = (RecyclerView) view.findViewById(R.id.recycler_view);
layout_manager = new LinearLayoutManager(getContext());
recycler_view.setLayoutManager(layout_manager);
adapter_recycler_view = new AdapterRV(filtered_advices_list);
recycler_view.setAdapter(adapter_recycler_view);
spinner_1 = (Spinner) view.findViewById(R.id.spinner_1);
adapter_spinner_1 = ArrayAdapter.createFromResource(view.getContext(), R.array.categories, android.R.layout.simple_spinner_item);
adapter_spinner_1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner_1.setAdapter(adapter_spinner_1);
spinner_1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView <?> parent, View view, int position, long id) {
String category = spinner_1.getItemAtPosition(spinner_1.getSelectedItemPosition()).toString();
model.setCategory(category);
}
@Override
public void onNothingSelected(AdapterView <?> parent) { }
});
return view;
}
}
show_advices_fragment
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="@color/colorBlueGreen"
android:paddingBottom="6dp">
<Spinner
android:id="@+id/spinner_1"
android:layout_width="match_parent"
android:layout_height="50dp"
android:backgroundTint="@color/colorBlack" />
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom">
<Button
android:id="@+id/button_add_activity"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_marginTop="6dp"
android:layout_marginLeft="6dp"
android:layout_marginRight="6dp"
android:visibility="gone"
android:text="@string/button_add_activity" />
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="@+id/button_add_activity"
android:background="@color/colorLightGrey"
android:scrollbars="vertical"
/>
</RelativeLayout>
</LinearLayout>
list_item_activity_main
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="4dp"
android:background="@color/colorWhite"
android:orientation="horizontal"
android:paddingBottom="5dp"
android:paddingTop="5dp"
android:paddingLeft="3dp"
android:paddingRight="3dp"
android:weightSum="3">
<TextView
android:id="@+id/text_view_advice"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/border"
android:textColor="@color/colorPrimary"
android:paddingRight="4dp"
android:layout_weight="1"
android:text="TextView" />
<TextView
android:id="@+id/text_view_author"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="@color/colorGrey"
android:layout_weight="2"
android:gravity="center"
android:text="TextView" />
</LinearLayout>
And test_item
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
android:duration="@android:integer/config_longAnimTime">
<translate
android:interpolator="@android:anim/decelerate_interpolator"
android:fromXDelta="100%p"
android:toXDelta="0"
/>
<alpha
android:fromAlpha="0.5"
android:toAlpha="1"
android:interpolator="@android:anim/accelerate_decelerate_interpolator"
/>
</set>
In the onResume I am in the last lifecycle I suppose and the recyclerview is being build up already in onCreateView. I guess that the build-up of the recyclerview aint finished before I reach onResume, but how can I solve this? If I do the animation with a mouseclick when the fragment is already loaded it works but not when I switch fragment and the recyclerview is being built up again.
