Android RecyclerView

public class ShowRecyclerAdapter extends RecyclerView.Adapter<ShowRecyclerAdapter.RecyclerViewHolder>{

private Context mContext;
private List<ShowData.DataBean> data;
public ShowRecyclerAdapter(Context context, List<ShowData.DataBean> data) {
     mContext = context;
     this.data = data;
}

@NonNull
@Override
public RecyclerViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
    View view=LayoutInflater.from(mContext).inflate(R.layout.recycler_item,viewGroup,false);
    RecyclerViewHolder holder=new RecyclerViewHolder(view);
    return holder;
}

@Override
public void onBindViewHolder(@NonNull RecyclerViewHolder recyclerViewHolder, int i) {
    recyclerViewHolder.showData.setText(data.get(i).getTitle());
    RecyclerView.LayoutParams params= (RecyclerView.LayoutParams) recyclerViewHolder.itemView.getLayoutParams();
    params.height= (int) (200+Math.random()*400);
    Picasso.with(mContext).load(data.get(i).getThumbnail_pic_s()).into(recyclerViewHolder.showImage);
    recyclerViewHolder.itemView.setLayoutParams(params);
}
@Override
public int getItemCount() {

    return data.size();
}

public class RecyclerViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    ImageView showImage;
    TextView showData;
    public RecyclerViewHolder(@NonNull View itemView) {
        super(itemView);
        showData=itemView.findViewById(R.id.model_data);
        showImage=itemView.findViewById(R.id.model_image);
       showData.setOnClickListener(this);
        showImage.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        int position = getPosition();
        mOnItemClickListener.onClick(v,position);
    }
}
OnItemClickListener mOnItemClickListener;
public interface OnItemClickListener{
    void onClick(View view,int postion);
}
public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
    mOnItemClickListener = onItemClickListener;
}

public void addData(){

    ShowData.DataBean dataBean=new ShowData.DataBean();
    dataBean.setTitle("呵呵");
    dataBean.setThumbnail_pic_s("http://thirdqq.qlogo.cn/qqapp/100424468/B853A0A0AC2A47327FE11D0A5E08D1D9/100");
    data.add(0,dataBean);
    notifyItemInserted(0);

}
public void delData(int postion){
    postion=postion-1;
    data.remove(postion);
    notifyItemRemoved(postion);

}
}