Appbar过渡动画(颤动)

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Appbar Transition Animation'),
          actions: [
            IconButton(
              icon: Icon(Icons.add),
              onPressed: () {
                // 触发动画
                _animateAppBar();
              },
            ),
          ],
        ),
        body: Center(child: Text('Hello World')),
      ),
    );
  }

  void _animateAppBar() {
    final appBar = AppBar.of(context);
    final originalTitle = appBar.title;
    appBar.title = Text('New Title');

    // 使用Tween动画实现颤动效果
    Tween<double>(begin: 0, end: 1).animate(CurvedAnimation(
      parent: AnimationController(
        duration: const Duration(milliseconds: 200),
        vsync: this,
      ),
    )).addListener(() {
      appBar.title = Text(
        originalTitle.text,
        style: TextStyle(fontSize: 16 + 4 * _animation.value),
      );
    });

    // 启动动画
    AnimationController controller = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 200),
    );
    controller.forward().then((_) {
      appBar.title = originalTitle;
    });
  }
}