Flutter 从外部类动态更改IconButton的图标

我有一个浮动按钮，我想根据从外部类接收的图标来动态更改图标.

这里: child: Icon(widget.icon, size: 50, color: themeProvider.titleColor)个

class TaskButton extends StatefulWidget {
  final IconData? icon;
  const TaskButton({super.key, this.icon});

  @override
  State<TaskButton> createState() => _TaskButtonState();
}

class _TaskButtonState extends State<TaskButton> {
  @override
  Widget build(BuildContext context) {
    var themeProvider = Provider.of<ThemeProvider>(context);
    return Positioned(
        bottom: 16.0,
        right: 16.0,
        width: 80,
        height: 80,
        child: Builder(
          builder: (context) => FloatingActionButton(
            onPressed: () {
              [...]
            },
            backgroundColor: themeProvider.selectedColor,
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(40.0),
            ),
            child: Icon(widget.icon, size: 50, color: themeProvider.titleColor),
          ),
        ));
  }
}

然后，在外部类中，我try 通过告诉TaskButton一个图标来构造TaskButton，该图标会根据tabController的当前索引进行更改.

这里: TaskButton(icon: getIconForTab(_tabController.index))个

class MainHome extends StatefulWidget {
  const MainHome({super.key});

  @override
  State<MainHome> createState() => _MainHomeState();
}

class _MainHomeState extends State<MainHome>
    with SingleTickerProviderStateMixin {
  late TabController _tabController;

  @override
  void initState() {
    super.initState();
    _tabController = TabController(length: 3, vsync: this);
  }

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

  @override
  Widget build(BuildContext context) {
    var themeProvider = Provider.of<ThemeProvider>(context);
    return Scaffold(
        [...]
          bottom: TabBar(
              controller: _tabController,
              unselectedLabelColor: Colors.grey,
              labelColor: themeProvider.selectedColor,
              dividerColor: Colors.transparent,
              indicatorSize: TabBarIndicatorSize.tab,
              tabs: const [
                Tab(icon: Icon(Icons.task_alt_rounded)),
                Tab(icon: Icon(Icons.alarm_add_rounded)),
                Tab(icon: Icon(Icons.edit_document)),
              ]),
        ),
        body: Stack(
          children: [
            TabBarView(
              controller: _tabController,
              children: const [
                GoalsTab(),
                AlarmsTab(),
                CheckTab(),
              ],
            ),
            TaskButton(
              icon: getIconForTab(_tabController.index),
            ),
          ],
        ));
  }
}

IconData getIconForTab(int index) {
  switch (index) {
    case 0:
      return Icons.add;
    case 1:
      return Icons.alarm_add_rounded;
    case 2:
      return Icons.edit_document;
    default:
      return Icons.add;
  }
}

我try 过处理状态，但我无法让TaskButton在每次收到图标时重新生成.

图标总是固定的，在构造过程中收到的第一个图标，所以当我从一个选项卡滑动到另一个选项卡进行 Select 或更改时，TaskButton图标保持固定.

class _TaskButtonState extends State<TaskButton> {
  late IconData? currentIcon;

  @override
  void initState() {
    super.initState();
    currentIcon = widget.icon;
  }

  @override
  void didUpdateWidget(covariant TaskButton oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (widget.icon != oldWidget.icon) {
      setState(() {
        currentIcon = widget.icon;
      });
    }
  }

  [...]

  child: Icon(currentIcon, size: 50, color: themeProvider.titleColor)

谢谢提前如果有人可以帮助我.