网络获取图片

方法一：异步任务实现

new AsyncTask<String, Void, Bitmap>() {


@Override
protected Bitmap doInBackground(String... params) {
String picUrl = params[0];
return DownLoadBitmap(picUrl);
}


protected void onPostExecute(Bitmap result) {
if (result != null) {
holder.imageView.setImageBitmap(result);
} else {
Toast.makeText(MainActivity.this, "网络取图片出错!",
Toast.LENGTH_SHORT).show();
}
};
}.execute(msg.getPicUrl());

/**
 * 根据图片址址从网络获取图片
 * 
 */
private Bitmap DownLoadBitmap(String httpUrl) {
URL url;
Bitmap bitmap = null;
HttpURLConnection connect = null;
InputStream is = null;
try {
url = new URL(httpUrl);
connect = (HttpURLConnection) url.openConnection();
is = connect.getInputStream();
bitmap = BitmapFactory.decodeStream(is);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (is != null) {
is.close();
}
if (connect != null) {
connect.disconnect();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return bitmap;
}

方法二：使用封装类实现 AsyncImageLoader

Bitmap bitmap=mAsyncImageLoader.loadBitmap(msg.getPicUrl(),new ImageCallbackForBitmap(){
@Override
public void imageLoaded(Bitmap bitmap, String imageUrl) {
holder.imageView.setImageBitmap(bitmap);
}
});

if(bitmap!=null){
holder.imageView.setImageBitmap(bitmap);
}

方法三：使用第三方工具包Picasso实现

Picasso.with(MainActivity.this).load(msg.getPicUrl()).into(holder.imageView);