How to get Access of a Recycler View's layout in an Activity (base java file)?

Question

Here is my Layout (fragment_hadees.xml) :

 <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Hadees">


    <androidx.recyclerview.widget.RecyclerView
        android:layout_width="match_parent"
        android:id="@+id/myrecyclerview"
        android:layout_height="match_parent"/>

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/fab"
        android:layout_alignParentEnd="true"
        android:layout_alignParentBottom="true"
        android:elevation="40dp"
        android:layout_margin="30dp"
       android:backgroundTint="#ffffff"
        android:src="@drawable/favorited"/>


</RelativeLayout>

Here is the Hadees.java (root java file) :

   @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment

    View root = inflater.inflate(R.layout.fragment_hadees, container, false);
   ((MainActivity) getActivity()).getSupportActionBar().setTitle("Hadees");

   HadeesAdapter hadeesAdapter;
   fab= root.findViewById(R.id.fab);
    ImageView copybutton= root.findViewById(R.id.copybutton);
    final TextView textView=root.findViewById(R.id.textView);
    ImageView whatsapText=root.findViewById(R.id.whatsApp_txt);


    toggleModelList= new ArrayList<>();

    fab.setOnClickListener(new View.OnClickListener() {
       @Override
       public void onClick(View view) {
          Toast.makeText(getActivity(), "FAB", Toast.LENGTH_SHORT).show();


       }
    });


    myrecyclerview=(RecyclerView)root.findViewById(R.id.myrecyclerview);
    myrecyclerview.setLayoutManager(new LinearLayoutManager(getActivity()));

Here is my hadees_contents.xml:

 <LinearLayout
    android:id="@+id/l1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">


    <TextView
        android:id="@+id/textView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_margin="10dp"
        android:textIsSelectable="true"
        android:textColor="#000000"
        android:gravity="center"
        android:maxLines="100"
        android:fontFamily="sans-serif-condensed-medium"
        android:text="This is Arabic Text"
        android:textSize="20sp" />

    <View
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:layout_marginTop="2dp"
        android:layout_marginBottom="2dp"
        android:background="@android:color/darker_gray" />

    <LinearLayout
        android:id="@+id/l2"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginTop="6dp"
        android:layout_marginBottom="6dp"
        android:weightSum="4">

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:id="@+id/copybutton"
            android:src="@drawable/ic_content_copy_black_24dp" />

How can I get Access to the the Views in the hadees_contents.xml in Hadees.java ? I have the access to FAB but not to the contents of Recycler's View inflated layout ,which is hadees_contents.xml

score 1 · Answer 1 · answered Nov 03 '19 at 19:32

You're trying to access the fields of hadees_contents from Hadees.java which doesn't inflate the xml hadees_contents. It inflates the xml fragment_hadees which is why you will get a null pointer exception if you try to access hadees_contents from Hadees.java. I can think of a way to solve this but I don't know if its practical in your situation. You must have an activity which adds the fields of hadees_contents into the recyclerview, you can send an intent from that addActivity which inflates hadees_contents to your Hadees.java class and receive it when you call the OnActivityResult method from Hadees.java.

score 1 · Answer 2 · answered Nov 03 '19 at 19:33

By calling the following method, no instances of hadees_contents.xml are inflated. It only inflates the RecyclerView itself which is an empty ViewGroup.

inflater.inflate(R.layout.fragment_hadees, container, false);

RecyclerViews need an adapter to tell them what to inflate and what data to bind to. Please refer to Simple Android RecyclerView example for further information and an example.

How to get Access of a Recycler View's layout in an Activity (base java file)?

2 Answers2