虽然位图似乎是正确的,但变量’userBitmap’将保持为null.但是,当我在平板电脑上向上或向下滚动时,新的列表行将包含图片,但它们都是相同和错误的.真的,真的很困惑.我尝试了许多不同的方法从网上获取图像.任何帮助是极大的赞赏.
我的定制适配器：
public class MessagesArrayAdapter extends ArrayAdapter
{
Bitmap userBitmap;
public MessageArrayAdapter(Context context, List objects)
{
super(context, 0, objects);
}
public View getView(int position, View convertView, ViewGroup parent)
{
ChatCell chatCell = new ChatCell();
LayoutInflater inflater = LayoutInflater.from(getContext());
convertView = inflater.inflate(R.layout.cell_chat, parent, false);
chatCell.usernameTextView = (TextView) convertView.findViewById(R.id.usernameTextView);
chatCell.messageTextView = (TextView) convertView.findViewById(R.id.messageTextView);
chatCell.userImageView = (ImageView) convertView.findViewById(R.id.userImageView);
ChatData chatData = getItem(position);
// Get user image from web
new loadImageAsync().execute(chatData.avatarURL);
chatCell.userImageView.setImageBitmap(userBitmap);
chatCell.usernameTextView.setText(chatData.username);
chatCell.messageTextView.setText(chatData.message);
return convertView;
}
private static class ChatCell
{
TextView usernameTextView;
TextView messageTextView;
ImageView userImageView;
}
private class loadImageAsync extends AsyncTask{
@Override
protected Double doInBackground(String... params) {
userBitmap = loadImage(params[0]);
return null;
}
}
public Bitmap loadImage(String str) {
InputStream instream = null;
try {
HttpGet httpRequest = new HttpGet(URI.create(str));
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = (HttpResponse) httpclient.execute(httpRequest);
HttpEntity entity = response.getEntity();
BufferedHttpEntity bufHttpEntity = new BufferedHttpEntity(entity);
instream = bufHttpEntity.getContent();
Bitmap myBitmap = BitmapFactory.decodeStream(instream);
return myBitmap;
} catch (Exception e) {
e.printStackTrace();
return null;
} finally {
//close input
if (instream != null) {
try {
instream.close();
} catch (IOException ioex) {
// Handle error
}
}
}
}
}
