Flutter多功能工具插件dynamic_tools的使用

Flutter多功能工具插件dynamic_tools的使用

dynamic_tools 是一个帮助开发者在 Flutter 中更方便地处理一些常用功能的插件。通过扩展 BuildContext，它简化了获取主题、屏幕尺寸等操作。

使用快捷方式通过 context

其实并没有什么神秘之处，只是对 BuildContext 的扩展，以便更容易地获取主题、屏幕大小、范围函数等。

示例

通常情况下，在构建方法中你会这样获取主题：

final theme = Theme.of(context);

但通过 dynamic_tools 可以更简单地实现：

final theme = context.theme;

类似地，当获取屏幕尺寸时：

final sizeScreen = MediaQuery.of(context).size;
final screenHeight = screen.height;

使用 dynamic_tools 可以简化为：

final screenHeight = context.screenHeight;

示例代码

下面是一个完整的示例，展示了如何使用 dynamic_tools 插件。

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

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

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

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      themeMode: context.isDarkMode ? ThemeMode.dark : ThemeMode.light,
      theme: ThemeData(
        useMaterial3: true,
        brightness: Brightness.light,
        colorSchemeSeed: Colors.blue,
      ),
      darkTheme: ThemeData(
        brightness: Brightness.dark,
        colorSchemeSeed: Colors.blue,
      ),
      initialRoute: '/home',
      routes: <String, WidgetBuilder>{
        '/home': (context) => const MyHomePage(),
        '/first': (context) => const FirstPage(),
        '/second': (context) => const SecondPage(),
      },
    );
  }
}

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

  [@override](/user/override)
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return PredictiveBack(
      leaveApp: true,
      child: Scaffold(
        appBar: AppBar(
          title: const Text('Demo'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              const Text(
                'Go to normal page',
              ),
              const SizedBox(height: 8),
              ElevatedButton(
                onPressed: () {
                  Navigator.of(context).pushNamed('/first');
                },
                child: const Icon(Icons.arrow_forward_outlined),
              ),
              const SizedBox(height: 16),
              const Text(
                'Go to predictive back page',
              ),
              const SizedBox(height: 8),
              ElevatedButton(
                onPressed: () {
                  Navigator.of(context).pushNamed('/second');
                },
                child: const Icon(Icons.arrow_forward_outlined),
              ),
              const SizedBox(height: 16),
              const Text(
                'You have pushed the button this many times:',
              ),
              Text(
                '$_counter',
                style: context.textTheme.headlineMedium, // 获取主题
              ),
            ],
          ),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: _incrementCounter,
          tooltip: '下一个',
          child: const Icon(Icons.add),
        ),
      ),
    );
  }
}

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

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('第一页面'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const Text('返回'),
            const SizedBox(height: 8),
            ElevatedButton(
              onPressed: () {
                Navigator.of(context).pop();
              },
              child: const Icon(Icons.arrow_back_outlined),
            ),
          ],
        ),
      ),
    );
  }
}

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

  [@override](/user/override)
  Widget build(BuildContext context) {
    return PredictiveBack(
      title: Text(
        '确定吗？',
        style: context.textTheme.titleMedium,
      ),
      child: Scaffold(
        appBar: AppBar(
          title: const Text('第二页面'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              const Text('返回'),
              const SizedBox(height: 8),
              ElevatedButton(
                onPressed: () {
                  Navigator.of(context).pop();
                },
                child: const Icon(Icons.arrow_back_outlined),
              ),
            ],
          ),
        ),
      ),
    );
  }
}