Android adapter (recycler views) with assyncTask image downloader
I use a adapter whith recycled views (holder). This is the code:
@Override public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.playlists_item, null);
holder = new ViewHolder();
holder.picture = (ImageView) convertView.findViewById(R.id.playlist_picture);
holder.name = (TextView) convertView.findViewById(R.id.playlist_name);
holder.desc = (TextView) convertView.findViewById(R.id.playlist_desc);
holder.play_bt = (ImageView) convertView.findViewById(R.id.playlist_play);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.picture.setImageResource(R.drawable.placeholder);
...
if(messages.get(position).containsKey("IMAGE"))
{
if(global.isInCache(messages.get(position).get("IMAGE")))
holder.picture.setImageBitmap(global.getBitmap(messages.get(position).get("IMAGE")));
else{
holder.picture.setTag("http://**********" + messages.get(position).get("IMAGE"));
new loadImageTask().execute(holder.picture,cache,messages.get(position).get("IMAGE"),"********/upload/********/");
}
}
And this is my downloader:
public class loadImageTask extends AsyncTask< Object , Void, Void> { ...
@Override
protected void onPreExecute() {
}
@Override
protected Void doInBackground(Object... params) {
imagem = (ImageView) params[0];
image_tag = (String)imagem.getTag();
caminho = (String) params[3];
name = (String) params[2];
imgLoad = LoadImageFromWeb(caminho+name);
return null;
}
@Override
protected void onPostExecute(Void result) {
if (imgLoad instanceof BitmapDrawable) {
bitmap = ((BitmapDrawable)imgLoad).getBitmap();
}
bitmap = getResizedBitmap(bitmap, 100, 100);
global.putCache(name, bitmap);
imagem.setImageBitmap(bitmap);
}
}
It turns out that when I scroll in listview when the download is finished, the image is loaded me in the position visible (and in the same position of the listview when scrolling is fast, the image is always being changed every time a download is finished).
I wish, if the position of the image that you are downloading to be done, is no longer visible, it is not done setImageBitmap
Thank you and sorry my English.
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