适配器

public class MyAdapter extends BaseAdapter {
    private List<Result.NewslistBean>list;
    private Context context;
    private DisplayImageOptions options;

    public MyAdapter(List<Result.NewslistBean> list, Context context) {
        this.list = list;
        this.context = context;
        options = new DisplayImageOptions.Builder()
                .cacheInMemory(true)//使用内存缓存
                .cacheOnDisk(true)//使用磁盘缓存
                .showImageOnLoading(R.mipmap.ic_launcher)//设置正在下载的图片
                .showImageForEmptyUri(R.mipmap.ic_launcher)//url为空或请求的资源不存在时
                .showImageOnFail(R.mipmap.ic_launcher)//下载失败时显示的图片
                .bitmapConfig(Bitmap.Config.RGB_565)//设置图片色彩模式 1px=2字节
                .imageScaleType(ImageScaleType.EXACTLY)//设置图片的缩放模式
                .displayer(new RoundedBitmapDisplayer(100))//设置圆角 30代表半径 自定义
                .build();

    }

    @Override
    public int getCount() {
        return list.size();
    }

    @Override
    public Object getItem(int position) {
        return list.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView==null){
            convertView=View.inflate(context, R.layout.layout,null);
            holder=new ViewHolder();
          holder.tv = convertView.findViewById(R.id.tv);
          holder.img=convertView.findViewById(R.id.img);
convertView.setTag(holder);
        }else {
            holder= (ViewHolder) convertView
                    .getTag();
        }
        holder.tv.setText(list.get(position).getTitle());

        ImageLoader.getInstance().displayImage(list.get(position).getPicUrl(),holder.img,options);

        return null;
    }
    class ViewHolder{
        TextView tv;
        ImageView img;
    }
}