title: Facebook Access Token always null
body: <p>I have some code in my main Activity which calls My facebook Login activity class if AccessToken.getCurrentAccessToken() is null:</p>
  
  <pre><code>import android.content.Intent;
  import android.os.Bundle;
  import android.support.v7.app.AppCompatActivity;
  import android.util.Log;
  import android.widget.Toast;
  
  import com.facebook.AccessToken;
  import com.facebook.AccessTokenTracker;
  import com.facebook.CallbackManager;
  import com.facebook.FacebookCallback;
  import com.facebook.FacebookException;
  import com.facebook.Profile;
  import com.facebook.ProfileTracker;
  import com.facebook.login.LoginManager;
  import com.facebook.login.LoginResult;
  
  import java.util.Arrays;
  
  import matthewboyle.lurker_android.MainFeedScreen;
  import matthewboyle.lurker_android.utilities.ConnectionChecker;
  
  /**
   * Created by matthewboyle on 28/05/2017.
   */
  
  public class FacebookLogin extends AppCompatActivity {
      private CallbackManager mCallbackManager;
      private AccessTokenTracker accessTokenTracker;
      private ProfileTracker profileTracker;
  
      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
  
          mCallbackManager = CallbackManager.Factory.create();
          accessTokenTracker = new AccessTokenTracker() {
              @Override
              protected void onCurrentAccessTokenChanged(AccessToken oldAccessToken, AccessToken currentAccessToken) {
                  Log.d("facebook", "onCurrentAccessTokenChanged");
  
  
              }
          };
          profileTracker = new ProfileTracker() {
              @Override
              protected void onCurrentProfileChanged(Profile oldProfile, Profile currentProfile) {
                  Log.d("facebook", "onCurrentProfileChanged");
  
              }
          };
          accessTokenTracker.startTracking();
          profileTracker.startTracking();
  
          LoginManager.getInstance().registerCallback(mCallbackManager,
                  new FacebookCallback&lt;LoginResult&gt;() {
                      @Override
                      public void onSuccess(LoginResult loginResult) {
                          Log.d("facebook", "in on success");
                          AccessToken accessToken = loginResult.getAccessToken();
                          Log.d("permissions", accessToken.getPermissions().toString());
  
                          Log.d("facebook", "in on success,got a token and its "+accessToken);
  
                      }
  
                      @Override
                      public void onCancel() {
                          Log.d("facebook", "in cancel");
  
                      }
  
                      @Override
                      public void onError(FacebookException exception) {
                          Log.d("facebook", "in error");
                          Log.d("facebook", exception.toString());
  
  
  
  
                      }
  
  
                  });
          LoginManager.getInstance().logInWithReadPermissions(this, Arrays.asList("public_profile", "user_posts","user_likes","user_about_me","user_managed_groups","user_tagged_places"));
          Log.d("facebook", "Done so redirecting with "+AccessToken.getCurrentAccessToken());
  
          startActivity(new Intent(FacebookLogin.this,MainFeedScreen.class));
  
  
      }
      @Override
      protected void onActivityResult(int requestCode, int responseCode, Intent intent) {
          super.onActivityResult(requestCode, responseCode, intent);
          //Facebook login
          mCallbackManager.onActivityResult(requestCode, responseCode, intent);
  
      }
  }
  </code></pre>
  
  <p>If I run this code, the only print statement I get is:</p>
  
  <pre><code> Done so redirecting with null
  </code></pre>
  
  <p>It doesn't seem to hit any other method in the class at all.</p>
  
  <p>It is worth mentioning that this code worked fine until I reinstalled the app. I went onto Facebook and updated the hash key in my app but that didn't seem to help. However, I'm not seeing any errors due to hash key.</p>
  
  <p>Would appreciate any help.</p>