在recylerview android中更改特定项目的颜色

Question

hello i want to change the color of specific items in recycler view. i have done this using this code.

public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyViewHolder> {

LayoutInflater inflater;
Context context;
clickME click;
View view;

ArrayList<String > data;

public CustomAdapter(Context context,ArrayList<String> data) {
    this.context=context;
    this.data=data;
    inflater= LayoutInflater.from(context);

}

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

    view=inflater.inflate(R.layout.list_row,parent,false);

    MyViewHolder holder=new MyViewHolder(view);
    return holder;
}

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


    int select=4;
    if(select == position) {
        view.setBackgroundColor(Color.BLUE);
        Toast.makeText(context,""+position,Toast.LENGTH_SHORT).show();
    } else {
        view.setBackgroundColor(Color.parseColor("#214F4B"));
         Toast.makeText(context,""+position,Toast.LENGTH_SHORT).show();

    }
    holder.tv_title.setText(data.get(position));



}

but the output is

i have successfully change the background color of item in position 4, but when i scroll down the background color of item at position 14 also change. i don't know why this happening kindly solve my issue

Answer 1

The problem is you're not recycling your view View. You have not posted your ViewHolder code, but you should use holder.view.setBackgroundColor(...) instead of view.setBackgroundColor(...) in your onBindViewHolder method.

Answer 2

You shouldn't reuse view from onCreateViewHolder() . Code will be something like this:

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

    View view = inflater.inflate(R.layout.list_row, parent, false);

    MyViewHolder holder = new MyViewHolder(view);
    return holder;
}

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

    int select = 4;
    if (select == position) {
        holder.itemView.setBackgroundColor(Color.BLUE);
        Toast.makeText(context, "" + position, Toast.LENGTH_SHORT).show();
    } else {
        holder.itemView.setBackgroundColor(Color.parseColor("#214F4B"));
        Toast.makeText(context, "" + position, Toast.LENGTH_SHORT).show();
    }
    holder.tv_title.setText(data.get(position));
}