title: Can't Override onPostExecute() method in AsyncTask Class or get it to trigger
body: <p>I am having trouble getting the <code>onPostExecute()</code> method to call when running an <code>AsyncTask</code>. When I try to set up my class extending <code>AsyncTask</code> in which the <code>onPostExecute()</code> is overridden I get the following build error.</p>
  
  <blockquote>
    <p>'The method onPostExecute() of type AsyncTaskExampleActivity must
    override or implement a supertype method'</p>
  </blockquote>
  
  <p>I have tried getting rid of the <code>@Override</code> annotation. This gets rid of the build error but the method still does not execute. If any one would be so kind as to point out what I'm overlooking I would greatly appreciated it.</p>
  
  <p>Code:</p>
  
  <pre><code>package com.asynctaskexample;
  
  import android.os.AsyncTask;
  
  public class AsyncTaskExampleActivity extends AsyncTask&lt;Void, Void, Void&gt; {
  
  AsyncTaskExampleActivity(){
  super();
      }
  
  @Override
  protected void onPreExecute() {
      }
  
  @Override
  protected Void doInBackground(Void... params) {
      return null;
  }
  
  @Override
  protected void onPostExecute() {
      }
  }
  </code></pre>