+                if (imageView != null) {
+                    // shows the default error icon
+                    imageView.setVisibility(View.VISIBLE);
+                } // else , silently finish, the fragment was destroyed
+            }
+            if (mMessageViewRef != null) {
+                final TextView messageView = mMessageViewRef.get();
+                if (messageView != null) {
+                    messageView.setText(mErrorMessageId);
+                    messageView.setVisibility(View.VISIBLE);
+                } // else , silently finish, the fragment was destroyed
+            }
+        }
+        
+        private void hideProgressWheel() {
+            if (mProgressWheelRef != null) {
+                final ProgressBar progressWheel = mProgressWheelRef.get();
+                if (progressWheel != null) {
+                    progressWheel.setVisibility(View.GONE);
+                }