Recyclerview触摸事件

Question

This is the first time I am working with RecyclerView , I have made Adapter class with some static mock data.

public static class ViewHolder extends RecyclerView.ViewHolder{

        public TextView textView;

        public ViewHolder(View view){

            super(view);

            textView = (TextView)view.findViewById(R.id.MyTextView);
        }
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        view1 = LayoutInflater.from(context).inflate(R.layout.item, parent ,false);

        Toast.makeText(context, "@@@@@@@@@@@@" +viewType, Toast.LENGTH_SHORT).show();

        viewHolder1 = new ViewHolder(view1);

        return viewHolder1;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {

        holder.textView.setText(SubjectValues[position]);
    }

    @Override
    public int getItemCount() {
        return SubjectValues.length;
    }
}

this is my Adapter clas now it's showing the mock data I want to achieve the click event.

Answer 1

In Adapter class, inside onBindViewHolder() method, you can register listener to the whole row as the following :

vh1.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
               // Toast.makeText(ComplexRecyclerViewAdapter.this, "Item no: "+ position, Toast.LENGTH_LONG).show;
                Toast.makeText(v.getContext(), "General click !", Toast.LENGTH_SHORT).show();
            }
        });

If you want to register listener to a specific view inside a row layout, you can do it as the following :

vh1.getButton().setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        // Toast.makeText(ComplexRecyclerViewAdapter.this, "Item no: "+ position, Toast.LENGTH_LONG).show;
        Toast.makeText(v.getContext(), "Button is clicked ! ", Toast.LENGTH_SHORT).show();
    }
});

The whole source code for the adapter class :

@Override
public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int position) {
    switch (viewHolder.getItemViewType()) {
        case USER:
            ViewHolder1 vh1 = (ViewHolder1) viewHolder;
            configureViewHolder1(vh1, position);
            break;
    }
}

private void configureViewHolder1(ViewHolder1 vh1, int position) {
    User user = (User) items.get(position);
    if (user != null) {
        vh1.getLabel1().setText("Name: " + user.name);
        vh1.getLabel2().setText("Hometown: " + user.hometown);

        vh1.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
               // Toast.makeText(ComplexRecyclerViewAdapter.this, "Item no: "+ position, Toast.LENGTH_LONG).show;
                Toast.makeText(v.getContext(), "General click !", Toast.LENGTH_SHORT).show();
            }
        });
        vh1.getButton().setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Toast.makeText(ComplexRecyclerViewAdapter.this, "Item no: "+ position, Toast.LENGTH_LONG).show;
                Toast.makeText(v.getContext(), "Button is clicked ! ", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

ViewHolder1.java

public class ViewHolder1 extends RecyclerView.ViewHolder {

    private TextView label1, label2;

    private Button button;

    public ViewHolder1(View v) {
        super(v);
        ...
        button = (Button) v.findViewById(R.id.button);
    }

    public Button getButton() {
        return button;
    }

    public void setButton(Button button) {
        this.button = button;
    }
}

Answer 2

Inside your onBindViewHolder set OnClickListener

@Override
    public void onBindViewHolder(final HomeListAdapter.MainViewHolder homeViewHolder, final int position) {

        homeViewHolder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(this, "Item no: "+ position, LENGTH_SHORT).show;
            }
        });
}

Using this way will make items layout clickable not only a textview or button. If perticularly you want to give action on click of button or textveiew then you can use reference of those components eg holder.button.setOnClickListener(new OnClick..)......

Answer 3

To add a click event add the following into the onBindViewHolder method:

holder.textView.setOnClickListener(new OnClickListener() {
                public void onClick(View v) {
                    int adapterPos = holder.getAdapterPosition();
                    if(adapterPos != RecyclerView.NO_POSITION) {
                        Toast.makeText(context, SubjectValues[adapterPos], Toast.LENGTH_SHORT).show();
                    }
            }
        });

That would add a click listener to the textView which shows a toast of the value.
Note: I have made assumptions on what your SubjectValues is, as not included in your question.

But the important things to observe here are:

• holder.getAdapterPosition()
• Check position (!= RecyclerView.NO_POSITION)
• Set this in onBindViewHolder

I believe this is a fair summary of how to set a click listener within a recyclerview adapter.

Answer 4

add this class to your project

public RecyclerItemClickListener(Context context, OnItemClickListener listener) {
    mListener = listener;
    mGestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
        @Override
        public boolean onSingleTapUp(MotionEvent e) {
            return true;
        }
    });
}

@Override
public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
    View childView = view.findChildViewUnder(e.getX(), e.getY());
    if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
        mListener.onItemClick(childView, view.getChildAdapterPosition(childView));
        return true;
    }
    return false;
}

@Override
public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) {
}

@Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
}

public interface OnItemClickListener {
    void onItemClick(View view, int position);
}}

then in your RecyclerView use this

    myRecyclerView.addOnItemTouchListener(new RecyclerItemClickListener(this, new RecyclerItemClickListener.OnItemClickListener() {
        @Override
        public void onItemClick(View view, int position) {
            YourModel model = modelList.get(position);
      }
    }));

Answer 5

Add OnItemClickListener interface into your adapter.

OnItemClickListener mItemClickListener;

public interface OnItemClickListener {
    public void onItemClick(View view, int position);
}

public void setOnItemClickListener(
        final OnItemClickListener mItemClickListener) {
    this.mItemClickListener = mItemClickListener;
}

Implements OnItemClickListener on ViewHolder like below.

public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

    public TextView textView;

    public ViewHolder(View view){
        super(view);
        textView = (TextView)view.findViewById(R.id.MyTextView);
        view.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        if (mItemClickListener != null) {
            mItemClickListener.onItemClick(v, getAdapterPosition());
        }
    }       
}

In your Activity or Fragment setOnItemClickListener on your adapter.

 mAdapter.setOnItemClickListener(new OnItemClickListener() {
        @Override
        public void onItemClick(View view, int position) {
          // Do your stuff here when item clicked
        }
    });