Calling an async task from a button click in a listitem inside of a fragment

Question

My app has a NavigationDrawer activity that swaps fragments based on the selection. One of these fragments contains a listview with several buttons. The listview items themselves are not selectable, but the I need to handle the button clicks, which I'm able to do capture successfully in my custom adapter.

Here is my issue: some button clicks need to trigger an async task to call REST api urls. I'm not sure how to do this. I tried calling a static method on my fragment that would instantiate an instance of a private class (extends AsyncTask), but that won't work. I thought about making a private class inside my custom adapter that extends from AsyncTask, but that doesn't feel right. What's the proper way to do something like this?

Answer 1

It wouldn't be different then Async tasks from anywhere else. Take a look at the documentation

http://developer.android.com/intl/es/reference/android/os/AsyncTask.html

Create a class for your task

 private class DownloadFilesTask extends AsyncTask<URL, Integer, Long> {
 protected Long doInBackground(URL... urls) {
     int count = urls.length;
     long totalSize = 0;
     for (int i = 0; i < count; i++) {
         totalSize += Downloader.downloadFile(urls[i]);
         publishProgress((int) ((i / (float) count) * 100));
         // Escape early if cancel() is called
         if (isCancelled()) break;
     }
     return totalSize;
 }

 protected void onProgressUpdate(Integer... progress) {
     setProgressPercent(progress[0]);
 }

 protected void onPostExecute(Long result) {
     showDialog("Downloaded " + result + " bytes");
 }
}

Then create an instance of it in your onClick event

 new DownloadFilesTask().execute(url1, url2, url3);