@Override
 public void onDestroyView() {
   if (mWebView != null) {
     mWebView.destroy();
   }
   ButterKnife.reset(this);
   super.onDestroyView();
 }
 @Override
 public void onDestroyView() {
   ButterKnife.reset(this);
   super.onDestroyView();
 }