Flutter 06 动画

一、动画基本原理以及Flutter动画简介

1、动画原理:

在任何系统的Ul框架中,动画实现的原理都是相同的,即:在一段时间内,快速地多次改变Ul外观;由于人眼会产生视觉暂留,所以最终看到的就是一个“连续”的动画,这和电影的原理是一样的。

我们将UI的一次改变称为一个动画帧,对应一次屏幕刷新,而决定动画流畅度的一个重要指标就是帧率FPS(Frame Per Second),即每秒的动画帧数。

很明显,帧率越高则动画就会越流畅!一般情况下,对于人眼来说,动画帧率超过16FPS,就基本能看了,超过32FPS就会感觉相对平滑,而超过32FPS,大多数人基本上就感受不到差别了。

由于动画的每一帧都是要改变Ul输出,所以在一个时间段内连续的改变Ul输出是比较耗资源的,对设备的软硬件系统要求都较高,所以在Ul系统中,动画的平均帧率是重要的性能指标,而在Flutter中,理想情况下是可以实现60FPS的,这和原生应用能达到的帧率是基本是持平的。

2、FLutter中的动画主要分为:

隐式动画、显式动画、自定义隐式动画、自定义显式动画、Hero动画;

二、隐式动画:

1、说明:

通过几行代码就可以实现隐式动画,由于隐式动画背后的实现原理和繁琐的操作细节都被隐去了,所以叫隐式动画,FLutter中提供的 AnimatedContainer、AnimatedPadding、AnimatedPositioned、AnimatedOpacity、AnimatedDefaultTextStyle、AnimatedSwitcher都属于隐式动画。

隐式动画中可以通过 duration配置动画时长、可以通过 Curve(曲线)来配置动画过程。

2、Curves曲线值:

linear 匀速的;
decelerate 匀减速;
ease 开始加速,后面减速;
easeln 开始慢,后面快;
easeOut 开始快,后面慢;
easelnOut 开始慢,然后加速,最后再减速;

3、AnimatedContainer:

AnimatedContainer的属性和Container属性基本是一样的,当AnimatedContainer属性改变的时候就会触发动画。

代码示例:放大缩小动画

Flutter 06 动画_第1张图片Flutter 06 动画_第2张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.animation),
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
      ),
      appBar: AppBar(
        title: const Text("AnimatedContainer Demo"),
      ),
      body: Center(
        child: AnimatedContainer(
          duration: const Duration(milliseconds: 500),
          // 动画时长500 ms width: flag?100:300,
          height: flag ? 100 : 300,
          color: Colors.blue,

        ),
      ),
    );
  }
}

4、AnimatedPadding:

代码示例:上下移动动画
Flutter 06 动画_第3张图片Flutter 06 动画_第4张图片
import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.animation),
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
      ),
      appBar: AppBar(
        title: const Text("AnimatedContainer Demo"),
      ),
      body: AnimatedPadding(
        duration: const Duration(milliseconds: 2000),
        // 动画时长500 ms curve: Curves.bounceInOut,
        padding: EdgeInsets.fromLTRB(10, flag ? 10 : 500, 0, 0),

        child: Container(
          width: 100,
          height: 100,
          color: Colors.red,
        ),
      ),
    );
  }
}

5、AnimatedPositioned:

代码示例:对角线移动动画

Flutter 06 动画_第5张图片Flutter 06 动画_第6张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

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

class MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("AnimatedPositioned Demo"),
      ),
      body: Stack(
        children: [
          AnimatedPositioned(
            curve: Curves.easeInOut,
            duration: const Duration(seconds: 1),
            top: flag ? 10 : 500,
            left: flag ? 10 : 300,
            child: Container(
              width: 60,
              height: 60,
              color: Colors.blue,
            ),
          ),
          Align(
            alignment: const Alignment(0, 0.8),
            child: ElevatedButton(
              child: const Text("Transform"),
              onPressed: () {
                setState(() {
                  flag = !flag;
                });
              },
            ),
          ),
        ],
      ),
    );
  }
}

6、AnimatedOpacity:

代码示例:淡入淡出动画

Flutter 06 动画_第7张图片Flutter 06 动画_第8张图片

import 'dart:isolate';
import 'dart:math';

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {


    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

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

class MyHomePageState extends State {
  bool flag = true;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        onPressed: (){
          setState(() {
            flag= !flag;
          });
        },
        child: const Icon(Icons.opacity),
      ),
      appBar: AppBar(
        title: const Text("AnimatedPositioned Demo"),
      ),
      body: Center(
        child: AnimatedOpacity(
          curve: Curves.linear,
          duration: const Duration(seconds: 1),
          opacity: flag?1:0,
          child: Container(
            width: 300,
            height: 300,
            color: Colors.blue,
          ),
        ),
      ),
    );
  }
}

7、AnimatedDefaultTextStyle:

代码示例:字体放大缩小动画

Flutter 06 动画_第9张图片Flutter 06 动画_第10张图片

import 'dart:isolate';
import 'dart:math';

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

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

class _MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
        child: const Icon(Icons.opacity),
      ),
      appBar: AppBar(
        title: const Text("AnimatedPositioned Demo"),
      ),
      body: Center(
        child: Container(
          alignment: Alignment.center,
          width: 300,
          height: 300,
          color: Colors.blue,
          child: AnimatedDefaultTextStyle(
            duration: const Duration(seconds: 1),
            style: TextStyle(
              fontSize: flag ? 20 : 50,
            ),
            child: const Text("你好Flutte"),
          ),
        ),
      ),
    );
  }
}

8、AnimatedSwitcher 和 transitionBuilder:

AnimatedContainer、AnimatedPadding、AnimatedPositioned、AnimatedOpacity、AnimatedDefaultTextStyle都是在属性改变的时候执行动画,AnimatedSwitcher则是在子元素改变的时候执行动画。

相比上面的动画组件AnimatedSwitcher多了transitionBuilder参数,可以在transitionBuilder中自定义动画

代码示例1、面前显示一个loading动画,加载完毕后显示对于的内容:

Flutter 06 动画_第11张图片Flutter 06 动画_第12张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

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

class _MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
        child: const Icon(Icons.opacity),
      ),
      appBar: AppBar(
        title: const Text("AnimatedPositioned Demo"),
      ),
      body: Center(
        child: Container(
          alignment: Alignment.center,
          width: 300,
          height: 180,
          color: Colors.yellow,
          child: AnimatedSwitcher(
            duration: const Duration(milliseconds: 1000),
            child: flag
                ? const CircularProgressIndicator()
                : Image.network(
                    "https://pics2.baidu.com/feed/b7003af33a87e9502b64d86f4c2e9544fbf2b45b.jpeg@f_auto?token=8c6557279177a75d44029840f0db0daa&s=C8AA67D91C0090457095310903005057",
                    fit: BoxFit.contain,
                  ),
          ),
        ),
      ),
    );
  }
}
代码示例2、通过transitionBuilder自定义动画效果:

Flutter 06 动画_第13张图片

import 'dart:isolate';
import 'dart:math';

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

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

class _MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
        child: const Icon(Icons.opacity),
      ),
      appBar: AppBar(
        title: const Text("AnimatedPositioned Demo"),
      ),
      body: Center(
        child: Container(
          alignment: Alignment.center,
          width: 300,
          height: 180,
          color: Colors.yellow,
          child: AnimatedSwitcher(
            transitionBuilder: ((child, animation) {
              return ScaleTransition(
                scale: animation,
                child: FadeTransition(
                  opacity: animation,
                  child: child,
                ),
              );
            }),
            duration: const Duration(milliseconds: 400),
            child: flag
                ? const CircularProgressIndicator()
                : Image.network(
                    "https://pics2.baidu.com/feed/b7003af33a87e9502b64d86f4c2e9544fbf2b45b.jpeg@f_auto?token=8c6557279177a75d44029840f0db0daa&s=C8AA67D91C0090457095310903005057",
                    fit: BoxFit.contain,
                  ),
          ),
        ),
      ),
    );
  }
}
代码示例3、通过transitionBuilder改变子元素执行动画:

Flutter 06 动画_第14张图片Flutter 06 动画_第15张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

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

class _MyHomePageState extends State {
  bool flag = true;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
        child: const Icon(Icons.opacity),
      ),
      appBar: AppBar(
        title: const Text("AnimatedPositioned Demo"),
      ),
      body: Center(
        child: Container(
          alignment: Alignment.center,
          width: 300,
          height: 180,
          color: Colors.yellow,
          child: AnimatedSwitcher(
            transitionBuilder: ((child, animation) {
              return  ScaleTransition(
                scale: animation,
                child: FadeTransition(
                  opacity: animation,
                  child:child ,
                ),
              );
            }),
            duration: const Duration(milliseconds: 400),
            child: Text(key:UniqueKey(),flag?"你好Flutter":"你好世界",style: const TextStyle(fontSize: 30),),
          ),
        ),
      ),
    );
  }
}

三、显式动画:

1、说明:

常见的显式动画有RotationTransition、FadeTransition、 ScaleTransition、SlideTransition、Animatedlcon。在显示动画中开发者需要创建一个AnimationController,通过AnimationController控制动画的开始、暂停、重置、跳转、倒播等;

2、RotationTransition旋转 和 AnimationController

1)AnimationController普通用法:

Flutter 06 动画_第16张图片Flutter 06 动画_第17张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => MyHomePageState();
}

class MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    // TODO: implement initState
    _controller = AnimationController(
      // Vsync 机制可以理解为是显卡与显示器的通信桥梁,显卡在渲染每一帧之前会等待垂直同步信号,
      // 只有显示器完成了一次刷新时,发出垂直同步信号,显卡才会渲染下一帧,确保刷新率和帧率保
      // 持同步,以达到供需平衡的效果,防止卡顿现象。
      vsync:
      this,
      duration: const Duration(seconds: 1),);
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(

      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          RotationTransition(
            turns: _controller,
            child: const FlutterLogo(
              size: 100,
            ),
          ),
          const SizedBox(height: 40,),
          Padding(padding: const EdgeInsets.fromLTRB(10, 0, 0, 0), child: Wrap(
            spacing: 10,
            alignment: WrapAlignment.center,
            children: [
              ElevatedButton(onPressed: () {
                _controller.forward(); //正序播放一次
              }, child: const Text("Forward")),
              ElevatedButton(onPressed: () {
                _controller.reverse(); //倒序播放一次
              }, child: const Text("Reverse")),
              ElevatedButton(onPressed: () {
                _controller.stop(); //停止播放
              }, child: const Text("Stop")),
              ElevatedButton(onPressed: () {
                _controller.reset(); //重置
              }, child: const Text("rest")),
              ElevatedButton(onPressed: () {
                _controller.repeat(); //重复播放
              }, child: const Text("repeat"))
            ],
          ),)
        ],
      ),
    );
  }
}
2)IowerBound 和 upperBound:

AnimationController用于控制动画,它包含动画的启动forward()、停止 stop()、反向播放reverse()等方法。AnimationController 会在动画的每一帧,就会生成一个新的值。默认情况下,AnimationController 在给定的时间段内线性的生成从 0.0到1.0(默认区间)的数字,我们也可以通过 lowerbound 和 upperBound 来修改 AnimationController 生成数字的区间。

代码示例:

Flutter 06 动画_第18张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
// TODO: implement initState

    _controller = AnimationController(
        vsync: this,
        duration: const Duration(seconds: 1),
        lowerBound: 3, //第三圈转到第五圈
        upperBound: 5
    );

    _controller.addListener(() {
      print(_controller.value);
    });
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          RotationTransition(
            turns: _controller,
            child: const FlutterLogo(
              size: 100,
            ),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Wrap(
              spacing: 10,
              alignment: WrapAlignment.center,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
                ElevatedButton(
                    onPressed: () {
                      _controller.stop(); //停止播放
                    },
                    child: const Text("Stop")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reset(); //重置
                    },
                    child: const Text("rest")),
                ElevatedButton(
                    onPressed: () {
                      _controller.repeat(); //重复播放
                    },
                    child: const Text("repeat"))
              ],
            ),
          )
        ],
      ),
    );
  }
}

3、FadeTransition 淡入淡出

代码示例:

Flutter 06 动画_第19张图片Flutter 06 动画_第20张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {

    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          FadeTransition(
            opacity: _controller,
            child: const FlutterLogo(size: 80),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
              ],
            ),
          )
        ],
      ),
    );
  }
}

4、ScaleTransition缩放 和 Tween

默认情况下,AnimationController对象值的范围是[0.0,1.0]。如果我们需要构建Ul的动画值在不同的范围或不同的数据类型,则可以使用Tween来添加映射以生成不同的范围或数据类型的值

代码示例1、AnimationController控制动画:

Flutter 06 动画_第21张图片Flutter 06 动画_第22张图片

import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}
//示例1:AnimationController控制动画
class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
// TODO: implement initState

    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          ScaleTransition(
            scale: _controller,
            child: const FlutterLogo(size: 80),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
              ],
            ),
          )
        ],
      ),
    );
  }
}
代码示例2、AnimationController结合Tween控制动画:

Flutter 06 动画_第23张图片Flutter 06 动画_第24张图片

import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}
//示例2:AnimationController结合Tween控制动画
class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    // TODO: implement initState
    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          ScaleTransition(
            scale: _controller.drive(Tween(begin: 1, end: 2)),
            child: const FlutterLogo(size: 80),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
              ],
            ),
          )
        ],
      ),
    );
  }
}

5、SlideTransition平移

这是一负责平移的显示动画组件,使用时需要通过position属性传入一个Animated表示位移程度,通常借助Tween实现

代码示例1、_controller.drive驱动动画:左右移动

Flutter 06 动画_第25张图片Flutter 06 动画_第26张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
    );
  }

  @override
  void dispose() {
    _controller.dispose();

    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          SlideTransition(
              position: _controller.drive(
                  Tween(
                    begin: const Offset(0, 0),
                    end: const Offset(1.2, 0),
                  ),
              ),
            child: const FlutterLogo(size: 80),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
              ],
            ),
          ),
        ],
      ),
    );
  }
}
代码示例2、Tween. animate 驱动动画:左右移动

Flutter 06 动画_第27张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();

    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          SlideTransition(
            position: Tween(
                    begin: const Offset(0, 0),
                    end: const Offset(1.2, 0) //表示实际的位置向右移动自身宽度的1.2倍
                    )
                .animate(_controller),
            child: const FlutterLogo(size: 80),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
              ],
            ),
          )
        ],
      ),
    );
  }
}
代码示例3、链式操作修改动画效果:弹性上下移动

Flutter 06 动画_第28张图片Flutter 06 动画_第29张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
// TODO: implement initState

    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 1),
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          SlideTransition(
            position:
                Tween(begin: const Offset(0, -1), end: const Offset(0, 0.8))
                    .chain(CurveTween(curve: Curves.bounceIn))
                    .animate(_controller),
            child: const FlutterLogo(size: 80),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
              ],
            ),
          )
        ],
      ),
    );
  }
}
代码示例4、链式操作修改动动画执行时间:弹性上下移动

Flutter 06 动画_第30张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
// TODO: implement initState

    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 3),
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          SlideTransition(
            position:
                Tween(begin: const Offset(0, -1), end: const Offset(0, 0.8))
                    .chain(CurveTween(curve: Curves.bounceIn))
                    .chain(CurveTween(curve: const Interval(0.8, 1.0)))
                    .animate(_controller),
            child: const FlutterLogo(size: 80),
          ),
          const SizedBox(
            height: 40,
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(10, 0, 0, 0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                ElevatedButton(
                    onPressed: () {
                      _controller.forward(); //正序播放一次
                    },
                    child: const Text("Forward")),
                ElevatedButton(
                    onPressed: () {
                      _controller.reverse(); //倒序播放一次
                    },
                    child: const Text("Reverse")),
              ],
            ),
          )
        ],
      ),
    );
  }
}

四、Animatedlcon:

Animatedlcon顾名思义,是一个用于提供动画图标的组件,它的名字虽然是以Animated开头,但是他是一个显式动画组件,需要通过progress属性传入动画控制器,另外需要由lcon属性传入动画图标数据;

代码示例:旋转改变图标

Flutter 06 动画_第31张图片Flutter 06 动画_第32张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller =
        AnimationController(vsync: this, duration: const Duration(seconds: 1));
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.add),
        onPressed: () {
          _controller.forward();
        },
      ),
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Center(
        child: AnimatedIcon(
            //图标效果列表:https://api.flutter.dev/flutter/material/AnimatedIcons-class.html
            icon: AnimatedIcons.menu_close, progress: _controller, size: 40),
      ),
    );
  }
}

五、交错动画:

代码示例:

Flutter 06 动画_第33张图片Flutter 06 动画_第34张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  bool flag = true;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 6),
    )..repeat(reverse: true);
  }

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.refresh),
        onPressed: () {
          flag ? _controller.forward() : _controller.reverse();
          flag = !flag;
        },
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.center,
          children: [
            SlidingBox(
              controller: _controller,
              color: Colors.blue[200],
              curve: const Interval(0, 0.2),
            ),
            SlidingBox(
              controller: _controller,
              color: Colors.blue[400],
              curve: const Interval(0.2, 0.4),
            ),
            SlidingBox(
              controller: _controller,
              color: Colors.blue[600],
              curve: const Interval(0.4, 0.6),
            ),
            SlidingBox(
              controller: _controller,
              color: Colors.blue[800],
              curve: const Interval(0.6, 0.8),
            ),
            SlidingBox(
              controller: _controller,
              color: Colors.blue[900],
              curve: const Interval(0.8, 1.0),
            ),
          ],
        ),
      ),
    );
  }
}

class SlidingBox extends StatelessWidget {
  final AnimationController controller;
  final Color? color;
  final Curve curve;

  const SlidingBox(
      {super.key,
      required this.controller,
      required this.color,
      required this.curve});

  @override
  Widget build(BuildContext context) {
    return SlideTransition(
      position: Tween(begin: const Offset(0, 0), end: const Offset(0.3, 0))
          .chain(CurveTween(curve: Curves.bounceInOut))
          .chain(CurveTween(curve: curve))
          .animate(controller),
      child: Container(
        width: 220,
        height: 60,
        color: color,
      ),
    );
  }
}

六、自定义动画:

1、TweenAnimationBuilder自定义隐式动画

每当Tween的end发生变化的时候就会触发动画

代码示例1、大小变化:

Flutter 06 动画_第35张图片Flutter 06 动画_第36张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.refresh),
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
      ),
      body: Center(
        child: TweenAnimationBuilder(
            tween: Tween(begin: 100.0, end: flag ? 100.0 : 200.0),
            duration: const Duration(seconds: 1),
            builder: ((context, value, child) {
              return Icon(
                Icons.star,
                size: value,
              );
            })),
      ),
    );
  }
}
代码示例2、透明度变化:

Flutter 06 动画_第37张图片Flutter 06 动画_第38张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State {
  bool flag = true;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.refresh),
        onPressed: () {
          setState(() {
            flag = !flag;
          });
        },
      ),
      body: Center(
        child: TweenAnimationBuilder(
            tween: Tween(begin: 0.0, end: flag ? 0.0 : 1.0),
            duration: const Duration(seconds: 1),
            builder: ((context, value, child) {
              return Opacity(
                opacity: value,
                child: Container(
                  color: Colors.red,
                  width: 200,
                  height: 200,
                ),
              );
            })),
      ),
    );
  }
}

2、AnimatedBuilder 自定义显式动画

代码示例1、透明度动画:

Flutter 06 动画_第39张图片Flutter 06 动画_第40张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller =
        AnimationController(vsync: this, duration: const Duration(seconds: 1))
          ..repeat(reverse: true);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Center(
        child: AnimatedBuilder(
          animation: _controller,
          builder: (BuildContext context, Widget? child) {
            return Opacity(
              opacity: _controller.value, //从0到1的变化
              child: Container(
                width: 200,
                height: 200,
                color: Colors.red,
                child: const Text("我是一个text组件"),
              ),
            );
          },
        ),
      ),
    );
  }
}
代码示例2、自定义变化范围:

Flutter 06 动画_第41张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller =
        AnimationController(vsync: this, duration: const Duration(seconds: 1))
          ..repeat(reverse: true);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Center(
        child: AnimatedBuilder(
          animation: _controller,
          builder: (BuildContext context, Widget? child) {
            return Opacity(
              opacity: Tween(begin: 0.5, end: 1.0)
                  .animate(_controller)
                  .value, //从0.5到1的变化

              child: Container(
                width: 200,
                height: 200,
                color: Colors.red,
                child: const Text("我是一个text组件"),
              ),
            );
          },
        ),
      ),
    );
  }
}
代码示例3、位置变化:

Flutter 06 动画_第42张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller =
        AnimationController(vsync: this, duration: const Duration(seconds: 1))
          ..repeat(reverse: true);
  }

  @override
  Widget build(BuildContext context) {
    Animation x = Tween(begin: -100.0, end: 100.0)
        .chain(CurveTween(curve: Curves.easeIn))
        .chain(CurveTween(curve: const Interval(0.2, 0.8)))
        .animate(_controller);
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Center(
        child: AnimatedBuilder(
          animation: _controller,
          builder: (BuildContext context, Widget? child) {
            return Container(
              width: 200,
              height: 200,
              color: Colors.red,
              transform: Matrix4.translationValues(x.value, 0, 0),
              child: const Text("我是一个text组件"),
            );
          },
        ),
      ),
    );
  }
}
代码示例4、child优化:

Flutter 06 动画_第43张图片

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

// This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends State
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller =
        AnimationController(vsync: this, duration: const Duration(seconds: 1))
          ..repeat(reverse: true);
  }

  @override
  Widget build(BuildContext context) {
    Animation x = Tween(begin: -100.0, end: 100.0)
        .chain(CurveTween(curve: Curves.easeIn))
        .chain(CurveTween(curve: const Interval(0.2, 0.4)))
        .animate(_controller);
    return Scaffold(
      appBar: AppBar(
        title: const Text('Title'),
      ),
      body: Center(
        child: AnimatedBuilder(
          animation: _controller,
          builder: (BuildContext context, Widget? child) {
            return Container(
              width: 200,
              height: 200,
              color: Colors.red,
              transform: Matrix4.translationValues(x.value, 0, 0),
              child: child,
            );
          },
          child: const Text("我是一个text组件"),
        ),
      ),
    );
  }
}

七、Hero 动画:

1、Hero动画的使用:

微信朋友圈点击小图片的时候会有一个动画效果到大图预览,这个动画效果就可以使用Hero动画实现。

Hero 指的是可以在路由(页面)之间“飞行”的widget,简单来说 Hero 动画就是在路由切换时,有一个共享的widget 可以在新旧路由间切换。

代码示例:

Flutter 06 动画_第44张图片Flutter 06 动画_第45张图片

home.dart:
import 'package:flutter/material.dart';
import '../../res/listData.dart';
import 'hero.dart';
import 'hero2.dart';

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

  @override
  State createState() => _HomePageState();
}

class _HomePageState extends State {
  List _getListData() {
    var tempList = listData2.map((value) {
      return GestureDetector(
        onTap: () {
          Navigator.push(context, MaterialPageRoute(builder: (setting) {
            // return HeroPage(arguments: {
            //   "imageUrl": value['imageUrl'],
            //   "description": value['title'],
            // });
            return HeroPage(arguments: {
              "imageUrl": value['imageUrl'],
              "description": value['title'],
            });
          }));
        },
        child: Container(
            decoration: BoxDecoration(
                border: Border.all(
                    color: const Color.fromRGBO(233, 233, 233, 0.9), width: 1)),
            child: Column(
              children: [
                Hero(
                  tag: value['title'],
                  // child: Image.asset(value['imageUrl'])),
                  child: Image.network(
                    value['imageUrl'],
                    width: 320,
                    height: 120,
                    fit: BoxFit.cover,
                  ),
                ),
                const SizedBox(height: 12),
                Text(
                  value['title'],
                  textAlign: TextAlign.center,
                  style: const TextStyle(fontSize: 20),
                )
              ],
            )),
      );
    });
    return tempList.toList();
  }

  @override
  Widget build(BuildContext context) {
    return GridView.count(
      crossAxisSpacing: 10.0,
      //水平子 Widget 之间间距
      mainAxisSpacing: 10.0,
      //垂直子 Widget 之间间距
      padding: const EdgeInsets.all(10),
      crossAxisCount: 2,
      //一行的 Widget 数量
      // childAspectRatio:0.7,
      // 宽度和高度的比例
      children: _getListData(),
    );
  }
}
hero.dart:
import 'package:flutter/material.dart';

class HeroPage extends StatefulWidget {
  final Map arguments;

  const HeroPage({super.key, required this.arguments});

  @override
  State createState() => _HeroPageState();
}

class _HeroPageState extends State {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("详情页面"),
      ),
      body: ListView(
        children: [
          Hero(
              tag: widget.arguments["imageUrl"],
              child: Image.network(widget.arguments["imageUrl"])),
          const SizedBox(height: 20),
          Padding(
            padding: const EdgeInsets.all(5),
            child: Text(widget.arguments["description"],
                style: const TextStyle(fontSize: 22)),
          )
        ],
      ),
    );
  }
}

2、Hero +photo_view 实现微信朋友圈图片预览:

Flutter 06 动画_第46张图片

photo_view预览图片: 

Flutter 06 动画_第47张图片 Flutter 06 动画_第48张图片Flutter 06 动画_第49张图片

代码示例:

Flutter 06 动画_第50张图片Flutter 06 动画_第51张图片

home.dart:
import 'package:flutter/material.dart';
import '../../res/listData.dart';
import 'hero.dart';
import 'hero2.dart';

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

  @override
  State createState() => _HomePageState();
}

class _HomePageState extends State {
  List _getListData() {
    var tempList = listData2.map((value) {
      return GestureDetector(
        onTap: () {
          Navigator.push(context, MaterialPageRoute(builder: (setting) {
            // return HeroPage(arguments: {
            //   "imageUrl": value['imageUrl'],
            //   "description": value['title'],
            // });
            return HeroPage2(arguments: {
              "imageUrl": value['imageUrl'],
              "description": value['title'],
            });
          }));
        },
        child: Container(
            decoration: BoxDecoration(
                border: Border.all(
                    color: const Color.fromRGBO(233, 233, 233, 0.9), width: 1)),
            child: Column(
              children: [
                Hero(
                  tag: value['title'],
                  // child: Image.asset(value['imageUrl'])),
                  child: Image.network(
                    value['imageUrl'],
                    width: 320,
                    height: 120,
                    fit: BoxFit.cover,
                  ),
                ),
                const SizedBox(height: 12),
                Text(
                  value['title'],
                  textAlign: TextAlign.center,
                  style: const TextStyle(fontSize: 20),
                )
              ],
            )),
      );
    });
    return tempList.toList();
  }

  @override
  Widget build(BuildContext context) {
    return GridView.count(
      crossAxisSpacing: 10.0,
      //水平子 Widget 之间间距
      mainAxisSpacing: 10.0,
      //垂直子 Widget 之间间距
      padding: const EdgeInsets.all(10),
      crossAxisCount: 2,
      //一行的 Widget 数量
      // childAspectRatio:0.7,
      // 宽度和高度的比例
      children: _getListData(),
    );
  }
}
hero2.dart:
import 'package:flutter/material.dart';
import 'package:photo_view/photo_view.dart';

class HeroPage2 extends StatefulWidget {
  final Map arguments;
  const HeroPage2({super.key, required this.arguments});

  @override
  State createState() => _HeroPageState();
}

class _HeroPageState extends State {
  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: () {
        Navigator.pop(context);
      },
      child: Hero(
        tag: widget.arguments["imageUrl"],
        child: Scaffold(
          backgroundColor: Colors.black,
          body: Center(
            child: AspectRatio(
              aspectRatio: 16 / 9,
              child: PhotoView(
                imageProvider: NetworkImage(widget.arguments["imageUrl"]),
              ),
            ),
          ),
        ),
      ),
    );
  }
}

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