item数量超过6条就会出现item重复，乱序

代码如下

fragment布局

recyclerview item布局

recycerview adapter

public class LightingRVAdapter extends RecyclerView.Adapter {

    private List mlist;
    private Context mContext;
    private LightingViewHolder viewHolder;

    public LightingRVAdapter(Context mContext, List mlist) {
        this.mContext = mContext;
        this.mlist = mlist;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.cardview_lighting, parent, false);
        viewHolder = new LightingViewHolder(v);
        return viewHolder;
    }

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

        Commodity c = mlist.get(position);
        viewHolder.mImageView.setText(c.getName());
        viewHolder.mTextView.setText(String.valueOf(c.getPrice_discont()));
    }

    @Override
    public int getItemCount() {
        return mlist == null ? 0 : mlist.size();
    }

    private class LightingViewHolder extends RecyclerView.ViewHolder
        implements View.OnClickListener
    {
        public TextView mTextView;

        public TextView mImageView;

        public LightingViewHolder(View v )
        {
            super(v);
            mTextView = (TextView) v.findViewById(R.id.name);
            mImageView = (TextView) v.findViewById(R.id.pic);
            mImageView.setOnClickListener(this);
        }

        @Override
        public void onClick(View view) {
            switch (view.getId()) {
                case R.id.pic :
                    mTextView.setText("OnChlic");
                    break;
            }
        }
    }

}