[flutter-chat-demo]2.dart

void _onBackPress() {
  _chatProvider.updateDataFirestore(
    FirestoreConstants.pathUserCollection,
    _currentUserId,
    {FirestoreConstants.chattingWith: null},
  );
  Navigator.pop(context);
}

void _getSticker() {
  // Hide keyboard when sticker appear
  focusNode.unfocus();
  setState(() {
    isShowSticker = !isShowSticker;
  });
}

void _onFocusChange() {
  if (focusNode.hasFocus) {
    // Hide sticker when keyboard appear
    setState(() {
      isShowSticker = false;
    });
  }
}