android gridview动态添加项目但面对重复的图像

Question

我使用了android gridview，我动态地将项目添加到imageAdapter，但是显示了重复的图像项目。我使用ViewHolder处理每个网格。 这是我的getView代码：

public View getView(final int position, View convertView, ViewGroup parent) {
    ViewHolder viewHolder;
    if (convertView == null) {
        convertView = LayoutInflater.from(mContext).inflate(R.layout.item_product_image, null);
        viewHolder = new ViewHolder();
        viewHolder.iv_image = (ImageView) convertView.findViewById(R.id.iv_image);
        viewHolder.iv_image.setId(position);
        viewHolder.iv_delete = (ImageView) convertView.findViewById(R.id.iv_delete);
        viewHolder.rl_grid = (RelativeLayout) convertView.findViewById(R.id.rl_grid);
        convertView.setTag(viewHolder);
    } else {
        viewHolder = (ViewHolder) convertView.getTag();
    }

    if(mImages.get(position) instanceof ParseFile) {
        int orientation = 0;
        try {
            orientation = Exif.getOrientation(((ParseFile)mImages.get(position)).getData());
        }catch(ParseException pe){
            Log.e("read Exif error", pe.getMessage());
        }
        Picasso.with(mContext)
                .load(((ParseFile)mImages.get(position)).getUrl())
                .placeholder(R.drawable.img_loading)
                .fit()
                .centerCrop()
                .rotate(orientation)
                .into(viewHolder.iv_image);

    }else if(mImages.get(position) instanceof byte[]){
            Bitmap bitmap = BitmapFactory.decodeByteArray((byte[])mImages.get(position), 0, ((byte[]) mImages.get(position)).length);
            viewHolder.iv_image.setImageBitmap(bitmap);
    }

    return convertView;
}