flutter - 如何在 Flutter 中使用 GetX 监听 FocusNode

Question

我刚刚发现 GetX我喜欢它!有没有一种使用 GetX 而不是使用 StatefulWidget 来监听 FocusNode 的巧妙方法？

class CustomTextField extends StatefulWidget {
  const CustomTextField({Key? key}) : super(key: key);

  @override
  _CustomTextFieldState createState() => _CustomTextFieldState();
}

class _CustomTextFieldState extends State<CustomTextField> {
  final FocusNode _focusNode = FocusNode();

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

  @override
  void dispose() {
    _focusNode.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return CustomContainer(
      isFocused: _focusNode.hasFocus,
      child: TextField(
        focusNode: _focusNode,
      ),
    );
  }
}

Answer 1

你可以创建一个StatelessWidget或 GetView<MyController>并在 Controller 中添加焦点节点

class MyController extends GetXController {
   final FocusNode focusNode = FocusNode();
   
   @override
   void onInit() {
        focusNode.addListener((){ ...do some stuff }));
        super.onInit();
   }

   @override
   onClose() {
     focusNode.dispose();
     super.onClose();
   }
}

然后你可以在你的小部件中使用它

...     
  @override
  Widget build(BuildContext context) {
    return CustomContainer(
      isFocused: controller.focusNode.hasFocus,
      child: TextField(
        focusNode: controller.focusNode.focusNode,
      ),
    );
  }