Flutter动画效果插件shimmer的使用

Shimmer

shimmer包为Flutter项目提供了一种简单的方法来添加闪亮的效果。

如何使用

首先，确保你已经在pubspec.yaml文件中添加了shimmer依赖：

dependencies:
  flutter:
    sdk: flutter
  shimmer: ^latest_version # 替换为最新版本号

然后，在你的Dart代码中导入shimmer：

import 'package:shimmer/shimmer.dart';

接下来，你可以通过以下方式创建一个带有闪亮效果的组件：

SizedBox(
  width: 200.0,
  height: 100.0,
  child: Shimmer.fromColors(
    baseColor: Colors.red,
    highlightColor: Colors.yellow,
    child: Text(
      'Shimmer',
      textAlign: TextAlign.center,
      style: TextStyle(
        fontSize: 40.0,
        fontWeight: FontWeight.bold,
      ),
    ),
  ),
);

示例Demo

下面是一个完整的示例demo，展示了如何在应用中使用shimmer插件。此示例包含两个页面：一个是加载列表页，另一个是滑动解锁页。

main.dart

import 'package:flutter/material.dart';
import 'package:shimmer/shimmer.dart';

void main() => runApp(const MyApp());

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Shimmer',
      routes: <String, WidgetBuilder>{
        'loading': (_) => const LoadingListPage(),
        'slide': (_) => SlideToUnlockPage(),
      },
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

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

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

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Shimmer'),
      ),
      body: Padding(
        padding: const EdgeInsets.symmetric(vertical: 8.0),
        child: Column(
          children: <Widget>[
            ListTile(
              title: const Text('Loading List'),
              onTap: () => Navigator.of(context).pushNamed('loading'),
            ),
            ListTile(
              title: const Text('Slide To Unlock'),
              onTap: () => Navigator.of(context).pushNamed('slide'),
            )
          ],
        ),
      ),
    );
  }
}

LoadingListPage

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

  @override
  State<LoadingListPage> createState() => _LoadingListPageState();
}

class _LoadingListPageState extends State<LoadingListPage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Loading List'),
      ),
      body: Shimmer.fromColors(
          baseColor: Colors.grey.shade300,
          highlightColor: Colors.grey.shade100,
          enabled: true,
          child: const SingleChildScrollView(
            physics: NeverScrollableScrollPhysics(),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              mainAxisSize: MainAxisSize.max,
              children: [
                BannerPlaceholder(),
                TitlePlaceholder(width: double.infinity),
                SizedBox(height: 16.0),
                ContentPlaceholder(
                  lineType: ContentLineType.threeLines,
                ),
                SizedBox(height: 16.0),
                TitlePlaceholder(width: 200.0),
                SizedBox(height: 16.0),
                ContentPlaceholder(
                  lineType: ContentLineType.twoLines,
                ),
                SizedBox(height: 16.0),
                TitlePlaceholder(width: 200.0),
                SizedBox(height: 16.0),
                ContentPlaceholder(
                  lineType: ContentLineType.twoLines,
                ),
              ],
            ),
          )),
    );
  }
}

SlideToUnlockPage

class SlideToUnlockPage extends StatelessWidget {
  final List<String> days = <String>[
    'Monday',
    'Tuesday',
    'Wednesday',
    'Thursday',
    'Friday',
    'Saturday',
    'Sunday'
  ];
  final List<String> months = <String>[
    'January',
    'February',
    'March',
    'April',
    'May',
    'June',
    'July',
    'August',
    'September',
    'October',
    'November',
    'December',
  ];

  SlideToUnlockPage({super.key});

  @override
  Widget build(BuildContext context) {
    final DateTime time = DateTime.now();
    final int hour = time.hour;
    final int minute = time.minute;
    final int day = time.weekday;
    final int month = time.month;
    final int dayInMonth = time.day;
    return Scaffold(
      appBar: AppBar(
        title: const Text('Slide To Unlock'),
      ),
      body: Stack(
        fit: StackFit.expand,
        children: <Widget>[
          Image.asset(
            'assets/images/background.jpg',
            fit: BoxFit.cover,
          ),
          Positioned(
            top: 48.0,
            right: 0.0,
            left: 0.0,
            child: Center(
              child: Column(
                children: <Widget>[
                  Text(
                    '${hour < 10 ? '0$hour' : '$hour'}:${minute < 10 ? '0$minute' : '$minute'}',
                    style: const TextStyle(
                      fontSize: 60.0,
                      color: Colors.white,
                    ),
                  ),
                  const Padding(
                    padding: EdgeInsets.symmetric(vertical: 4.0),
                  ),
                  Text(
                    '${days[day - 1]}, ${months[month - 1]} $dayInMonth',
                    style: const TextStyle(fontSize: 24.0, color: Colors.white),
                  )
                ],
              ),
            ),
          ),
          Positioned(
              bottom: 32.0,
              left: 0.0,
              right: 0.0,
              child: Center(
                child: Opacity(
                  opacity: 0.8,
                  child: Shimmer.fromColors(
                    baseColor: Colors.black12,
                    highlightColor: Colors.white,
                    child: Row(
                      mainAxisSize: MainAxisSize.min,
                      children: <Widget>[
                        Image.asset(
                          'assets/images/chevron_right.png',
                          height: 20.0,
                        ),
                        const Padding(
                          padding: EdgeInsets.symmetric(horizontal: 4.0),
                        ),
                        const Text(
                          'Slide to unlock',
                          style: TextStyle(
                            fontSize: 28.0,
                          ),
                        )
                      ],
                    ),
                  ),
                ),
              ))
        ],
      ),
    );
  }
}

以上代码展示了如何在Flutter应用中使用shimmer插件创建具有闪亮效果的界面。你可以根据需要调整颜色、大小和其他属性，以适应你的应用设计。