android

Question

我正在尝试使用 GridView + Picasso\Universal Image Loader 创建图库，但我遇到了一些问题。每次我只加载 local 文件（来自外部存储），而不是来自网络。我制作了两个视频，比文字更能描述问题。

我使用自定义适配器扩展 BaseAdapter。

thumbs 是 File 的数组，图片

毕加索

加载图像足够快，但滚动速度很慢。Here the video demonstration on youtube

    @Override
public View getView(int position, View convertView, ViewGroup parent) {

    //Get the view
    View view;
    if (convertView == null)
        view=inflater.inflate(R.layout.gallery_photo_item,parent,false);
    else
        view =  convertView;

    //find the componetnts
    final ImageView image_view = (ImageView)view.findViewById(R.id.galley_photo_item_image);
    final CheckBox check = (CheckBox)view.findViewById(R.id.galley_photo_item_checkbox);

    //Toggling checkbox if DELETE MODE
    if(is_checking) {
        check.setChecked(false);
        check.setVisibility(View.VISIBLE);
    }
    else
        check.setVisibility(View.INVISIBLE);

    view.setTag(position);
    check.setTag(position);

    //Some event handling
    check.setOnClickListener(this);
    view.setOnClickListener(this);

    //Setting up Picasso
    Picasso.Builder builder = new Picasso.Builder(context);
    builder.listener(new com.squareup.picasso.Picasso.Listener() {

        @Override
        public void onImageLoadFailed(Picasso picasso, Uri uri, Exception exception) {
            Log.e("Picasso","Loading failed: "+exception.getMessage());
            image_view.setVisibility(View.GONE);
        }

    });

    //Display image
    Picasso pic = builder.build();
    pic
            .load(thumbs[position])
            //.placeholder(R.drawable.ic_launcher)
            .fit()
            .into(image_view);


    return view;
}

通用图像加载器

滚动速度很快，但加载速度很慢。此外，当您快速滚动时，您会看到错误的图像，这些图像将在几秒钟内被正确的（当它们加载后）替换。 Demonstration on youtube

我在这里添加了 View Holder 模式。

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    ViewHolder view_holder;
    if(convertView==null)
    {
        convertView = inflater.inflate(R.layout.gallery_photo_item,parent,false);
        ImageView image = (ImageView)convertView.findViewById(R.id.galley_photo_item_image);
        CheckBox checkBox = (CheckBox)convertView.findViewById(R.id.galley_photo_item_checkbox);
        view_holder = new ViewHolder(convertView,image,checkBox);
        convertView.setTag(view_holder);
    }
    else
        view_holder = (ViewHolder)convertView.getTag();

    //Toggle checkbox on DELETE MODE
    if(is_checking) {
        view_holder.CheckBox.setChecked(false);
        view_holder.CheckBox.setVisibility(View.VISIBLE);
    }
    else
        view_holder.CheckBox.setVisibility(View.INVISIBLE);

    //view.setTag(position);
    //check.setTag(position);

    //Event handling
    view_holder.CheckBox.setOnClickListener(this);
    view_holder.View.setOnClickListener(this);

    //Display image
    String uri = Uri.fromFile(thumbs[position]).toString();
    ImageLoader loader = ImageLoader.getInstance();
    loader.displayImage(uri,view_holder.ImageView, options);


    return convertView;
}

问题

有什么好方法可以让图库运行得更快（作为本机 android 应用程序，完美）？

Answer 1

尝试使用 google 推荐的 Glide Image Loader Library 参考这里：- https://coderzpassion.com/android-working-glide-image-loader-library/

android - 带有 Picasso 或 Universal Image Loader 的厨房

android - galley with Picasso or Universal Image Loader

performance

picasso

universal-image-loader

毕加索

通用图像加载器

问题