How to use RecyclerView, Trying to follow developer.android.com suggestion but get error

Question

I'm trying to use RecyclerView to show my dataset, trying to follow this website https://developer.android.com/training/material/lists-cards.html

Problem is that there is some part wrong and can't find out how to fix it, I did exactly how that site suggest.

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
    private String[] mDataset;

    // Provide a reference to the views for each data item
    // Complex data items may need more than one view per item, and
    // you provide access to all the views for a data item in a view holder
    public static class ViewHolder extends RecyclerView.ViewHolder {
        // each data item is just a string in this case
        public TextView mTextView;
        public ViewHolder(TextView v) {
            super(v);
            mTextView = v;
        }
    }

    // Provide a suitable constructor (depends on the kind of dataset)
    public MyAdapter(String[] myDataset) {
        mDataset = myDataset;
    }

    // Create new views (invoked by the layout manager)
    @Override
    public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
                                               int viewType) {
        // create a new view
        View v = LayoutInflater.from(parent.getContext())
                           .inflate(R.layout.my_text_view, parent, false);
        // set the view's size, margins, paddings and layout parameters
        ...
        ViewHolder vh = new ViewHolder(v);     // ERROR
        return vh;
    }

    // Replace the contents of a view (invoked by the layout manager)
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        // - get element from your dataset at this position
        // - replace the contents of the view with that element
        holder.mTextView.setText(mDataset[position]);

    }

    // Return the size of your dataset (invoked by the layout manager)
    @Override
    public int getItemCount() {
        return mDataset.length;
    }
}

Android Studio gives me an error:

ViewHolder (android.widget.TextView) in ViewHolder cannot be applied
to         (android.view.View)

How should I do this?

It seems developer.android.com have some typo here?

Answer 1

When you inflate a view, it's usually a good idea to create an instance of the specific type of view that you are inflating. In this case you are inflating a TextView. Since TextView extends from View the compiler will not complain about it, but when you try to use the View as a TextView your app will crash.

// create a new view
TextView v = (TextView) LayoutInflater.from(parent.getContext())
                       .inflate(R.layout.my_text_view, parent, false);

Change View to TextView.