Picasso Library and GridView Images

问题:

I want to build an app that displays images in a gridview by using the picasso library. The images are retrieved by a remote server. Should I make an AsyncTask class or is this class handled by Picasso Library itself? All the picasso tutorials I have seen so far seem a bit vague.

Thanks,

Theo.

回答1:

Its very simple to use picasso lib for loading images in gridview, as demonstrated here,

class SampleGridViewAdapter extends BaseAdapter {
  private final Context context;
  private final List<String> urls = new ArrayList<String>();

  public SampleGridViewAdapter(Context context) {
    this.context = context;

    // Ensure we get a different ordering of images on each run.
    Collections.addAll(urls, Data.URLS);
    Collections.shuffle(urls);

    // Triple up the list.
    ArrayList<String> copy = new ArrayList<String>(urls);
    urls.addAll(copy);
    urls.addAll(copy);
  }

  @Override public View getView(int position, View convertView, ViewGroup parent) {
    SquaredImageView view = (SquaredImageView) convertView;
    if (view == null) {
      view = new SquaredImageView(context);
      view.setScaleType(CENTER_CROP);
    }

    // Get the image URL for the current position.
    String url = getItem(position);

    // Trigger the download of the URL asynchronously into the image view.
    Picasso.with(context) //
        .load(url) //
        .placeholder(R.drawable.placeholder) //
        .error(R.drawable.error) //
        .fit() //
        .tag(context) //
        .into(view);

    return view;
  }

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

  @Override public String getItem(int position) {
    return urls.get(position);
  }

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