图片的优化

public class BannerAdapter extends PagerAdapter {

    private List<BannerResponse.DataBean> mDatas;

    public BannerAdapter() {
        this.mDatas = new ArrayList<>();
    }
    public void setBannerDatas(List<BannerResponse.DataBean> datas){
        if (datas != null){
            mDatas = datas;
        }
        notifyDataSetChanged();
    }

    @Override
    public int getCount() {
        return mDatas.size() == 0 ? 0 : 50000;
        //return mDatas.size();
    }

    @Override
    public boolean isViewFromObject(@NonNull View view, @NonNull Object o) {
        return view == o;
    }

    @NonNull
    @Override
    public Object instantiateItem(@NonNull ViewGroup container, int position) {
        ImageView imageView = new ImageView(container.getContext());
        //图片如何缩放
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        ImageLoader.getInstance().displayImage(mDatas.get(position % mDatas.size()).getHttpIcon(),imageView);
        container.addView(imageView);
        return imageView;
    }

    @Override
    public void destroyItem(@NonNull ViewGroup container, int position, @NonNull Object object) {
        container.removeView((View) object);
    }
}


在这里插入代码片