title: Problems with AsyncTask
body: <pre><code>package com.example.helloandroid;
  
  import java.io.File;
  
  import android.os.AsyncTask;
  import android.os.Environment;
  import android.widget.Toast;
  
  public class CheckTask extends AsyncTask&lt;Void, Void, Boolean&gt; {
  
  
  
  protected Boolean doInBackground(Void... params) {
      while (true) {
          if (Environment.MEDIA_MOUNTED.equals(Environment
                  .getExternalStorageState())) {
              // access external file
              String f = Environment.getExternalStorageDirectory()
                      + "/schedule.rtf";
              File s = new File(f);
              if (s.exists()) {
                  return true;
  
              }
  
          }
      }
  
  }
  
  protected void onPostExecute(Boolean result) {
      if (result == true) {
  
  
           Toast.makeText(CheckTask.this, "Hello", Toast.LENGTH_SHORT).show();
  
      }
  }
  }
  </code></pre>
  
  <p>I keep getting the following error message:
  The method makeText(Context, CharSequence, int) in the type Toast is 
   not applicable for the arguments (CheckTask, String, int)</p>
  
  <p>I have tried searching some basic tutorials and they use Toast.makeText in the same way as above. I am not sure whats wrong.</p>
  
  <p>Thank you.</p>