Verify attached before showing a dialog

        @Override

        public void run() {

            if (mWebViewCore == null

                    || getWebView().getWindowToken() == null

                    || getWebView().getViewRootImpl() == null) {

                // We've been detached and/or destroyed since this was posted

                return;

            }

            final ListView listView = (ListView) LayoutInflater.from(mContext)

                    .inflate(com.android.internal.R.layout.select_dialog, null);

            final MyArrayListAdapter adapter = new MyArrayListAdapter();