Question

当我将图像从SD卡加载到ListView时，它开始滞后。我不能顺利滚动。所以，我决定使用Recycler view，也许是Picasso。我面临的唯一问题是，ListView适配器不能与RecyclerView一起使用。

如何重写以下代码/适配器以使用RecyclerView？

万事如意，新年快乐！

public class Saveditems extends BaseActivity {

ArrayList<String> f = new ArrayList<>();// list of file paths
File[] listFile;


@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.saveditems);

    activateToolbarWithHomeEnabled().setNavigationOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            finish();

        }

    });

    getFromSdcard();

    RecyclerView imagelist = (RecyclerView) findViewById(R.id.PhoneImageGrid);

    ImageAdapter imageAdapter = new ImageAdapter();

    imagelist.setAdapter(imageAdapter); //error
    //image adapter cannot be applied to recycler view

}

public void getFromSdcard() {

    File file = new File(Environment.getExternalStorageDirectory() + "/FlickrBrowser");

    if (file.isDirectory()) {

        listFile = file.listFiles();

        for (File aListFile : listFile) {

            f.add(aListFile.getAbsolutePath());

        }
    }
}

public class ImageAdapter extends BaseAdapter {
    private LayoutInflater mInflater;

    public ImageAdapter() {
        mInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    public int getCount() {
        return f.size();
    }

    public Object getItem(int position) {
        return position;
    }

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

    @SuppressLint("InflateParams")
    public View getView(int position, View convertView, ViewGroup parent) {

        ViewHolder holder;

        if (convertView == null) {

            holder = new ViewHolder();
            convertView = mInflater.inflate(
                    R.layout.galleryitem, null);
            holder.imageview = (ImageView) convertView.findViewById(R.id.thumbImage);

            convertView.setTag(holder);

        } else {

            holder = (ViewHolder) convertView.getTag();
        }

        Bitmap myBitmap = BitmapFactory.decodeFile(f.get(position));
        holder.imageview.setImageBitmap(myBitmap);
        return convertView;

    }

}

class ViewHolder {

    ImageView imageview;

}}

Answer 1

public class ImageAdapter extends RecyclerView.Adapter<ImageAdapter.ImageHolder> {

    List<String> f;

    public ImageAdapter(List<String> list) {

    f=list;

     }

    @Override
    public ImageHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.yourlayout, parent, false);
        return new ImageHolder(v);
    }

    @Override
    public void onBindViewHolder(final ImageHolder holder, final int position) {

        Bitmap myBitmap = BitmapFactory.decodeFile(f.get(position));
        holder.imageview.setImageBitmap(myBitmap);

    }

    public static class ImageHolder extends RecyclerView.ViewHolder {


    ImageView imageview;

    public ImageHolder(View itemView){
        super(itemView);
        imageview=(ImageView)itemView.findViewById(R.id.yourimageid)
    }

  }

}

将listview适配器更改为recycleler视图适配器

1 个答案: