Flutter 监听TextField焦点

Flutter   监听TextField焦点

  FocusNode _focusNode = FocusNode();
  bool isFocus = false;

  @override
  void initState() {
    super.initState();
    _focusNode.addListener(() {
      setState(() {
        isFocus = _focusNode.hasFocus;
      });
    });
  }

                  TextField(
           
                    focusNode: _focusNode,