Is there any simple implementation or tutorial to implement RecyclerView in android?

Question

I am trying to port my existing project to material design but am unable to understand the implementation of RecyclerView. My old code uses a ListView but I want GMail app l

Answer 1

RecyclerView Adapter Example:

1. Adapter issue can be solved using below code:

   public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder>         
   {
   
   private final Context mContext;
   private List<String> mData1, mData2;
   
   public MyAdapter(Context mContext, String[] data1, String[] data2) {
   this.mContext = mContext;
   if (data1 != null)
       mData1 = new ArrayList<String>(Arrays.asList(data1));
   else
       mData1 = new ArrayList<String>();
   
   if (data2 != null)
       mData2 = new ArrayList<String>(Arrays.asList(data2));
   else
       mData2 = new ArrayList<String>();
   }
   
   public void add(String s, int position) {
   position = position == -1 ? getItemCount() : position;
   mData1.add(position, s);
   
   notifyItemInserted(position);
   }
   
   public void remove(int position) {
   if (position < getItemCount()) {
       mData1.remove(position);
       notifyItemRemoved(position);
   }
   }
   
   @Override
   public MyViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
   LayoutInflater inflater = LayoutInflater.from(viewGroup.getContext());
   View itemView = inflater.inflate(R.layout.list_item, viewGroup, false);
   
   return new MyViewHolder(itemView);
   }
   
   @Override
   public void onBindViewHolder(MyViewHolder myViewHolder, final int position) {
       myViewHolder.tv1.setText(mData1.get(position));
   myViewHolder.tv2.setText(mData2.get(position));
   myViewHolder.itemView.setOnClickListener(new OnClickListener() {
   
       @Override
       public void onClick(View v) {
           // TODO Auto-generated method stub
           clickListener.onClick(v, position);
       }
   });
   }
   
   @Override
   public int getItemCount() {
   return mData1.size();
   }
   
   ClickListener clickListener;
   
   public void setClickListener(ClickListener clickListener) {
   this.clickListener = clickListener;
   }
   
   public interface ClickListener {
   public void onClick(View v, int pos);
   
   }
   
   public static class MyViewHolder extends RecyclerView.ViewHolder {
   protected TextView tv1;
   protected TextView tv2;
   
   public MyViewHolder(View itemView) {
       super(itemView);
       tv1 = (TextView) itemView.findViewById(R.id.txt1);
       tv2 = (TextView) itemView.findViewById(R.id.txt2);
   
   }
   
   }
   }
   

Usage is as below:

MyAdapter adapter=....;
adapter.setClickListener(new ClickListener() {

        @Override
        public void onClick(View v, int pos) {
            // do whatever you want
        }
    });

2. There is not any Simple way to do that. But i would suggest you one workaround for this. Add below view as a divider at the bottom inside your list_item.xml.

    <View
   android:layout_width="wrap_content"
   android:layout_height="0.5dip" 
   android:background="@color/light_gray"/>
   

3. Item click listener is also resolved in point no. 1 above.

I hope this would help you.

Answer 2

Here is example for Simple Implementation of RecyclerView using a Simple Library

Add this line in build.gradle

implementation 'com.hereshem.lib:awesomelib:2.0.1'

Create RecyclerView Layout in Activity with

<com.hereshem.lib.recycler.MyRecyclerView
        android:id="@+id/recycler"
        app:layoutManager="LinearLayoutManager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

Create a ViewHolder by passing the class it suppports

public static class EVHolder extends MyViewHolder<Events> {
    TextView date, title, summary;
    public EVHolder(View v) {
        super(v);
        date = v.findViewById(R.id.date);
        title = v.findViewById(R.id.title);
        summary = v.findViewById(R.id.summary);
    }
    @Override
    public void bindView(Events c) {
        date.setText(c.date);
        title.setText(c.title);
        summary.setText(c.summary);
    }
}

Create Items List variable and adapters with very few lines

List<Events> items = new ArrayList<>();
MyRecyclerView recycler = findViewById(R.id.recycler);
RecyclerViewAdapter adapter = new RecyclerViewAdapter(this, items, EVHolder.class, R.layout.row_event);
recycler.setAdapter(adapter);

ClickListener can be added with folllowing line

recycler.setOnItemClickListener(new MyRecyclerView.OnItemClickListener() {
    @Override
    public void onItemClick(int position) {
        Toast.makeText(MainActivity.this, "Recycler Item Clicked " + position, Toast.LENGTH_SHORT).show();
    }
});

More example can be found here

Hope this helps :)