flutter 常用代码片段

表格

你可以使用 Flutter 的 DataTable 组件来创建表格，并将其包装在 SingleChildScrollView 中以支持横向滚动。以下是一个简单的示例代码，用于创建包含 10 个属性的表格：

dart

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('Flutter DataTable'),
        ),
        body: SingleChildScrollView(
          scrollDirection: Axis.horizontal,
          child: DataTable(
            columnSpacing: 20.0,
            columns: <DataColumn>[
              DataColumn(
                label: Text(
                  '属性1',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性2',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性3',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性4',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性5',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性6',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性7',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性8',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性9',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
              DataColumn(
                label: Text(
                  '属性10',
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ),
            ],
            rows: List<DataRow>.generate(
              10,
              (int index) => DataRow(
                cells: <DataCell>[
                  DataCell(Text('值${index + 1}')),
                  DataCell(Text('值${index + 2}')),
                  DataCell(Text('值${index + 3}')),
                  DataCell(Text('值${index + 4}')),
                  DataCell(Text('值${index + 5}')),
                  DataCell(Text('值${index + 6}')),
                  DataCell(Text('值${index + 7}')),
                  DataCell(Text('值${index + 8}')),
                  DataCell(Text('值${index + 9}')),
                  DataCell(Text('值${index + 10}')),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }
}

appBar 下面添加内容，并且悬浮

dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: HomePage(),
    );
  }
}

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: CustomScrollView(
        slivers: <Widget>[
          SliverAppBar(
            pinned: true, // 设置AppBar固定在顶部
            expandedHeight: 200.0,
            flexibleSpace: FlexibleSpaceBar(
              title: Text('Page Title'),
            ),
          ),
          SliverToBoxAdapter(
            child: Container(
              color: Colors.grey.shade300,
              padding: const EdgeInsets.all(16.0),
              child: Text(
                '这里是AppBar下面的一行文字',
                style: TextStyle(fontSize: 18),
              ),
            ),
          ),
          // 列表内容
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (context, index) {
                return Container(
                  padding: const EdgeInsets.all(16.0),
                  color: Colors.primaries[index % Colors.primaries.length],
                  child: Text(
                    'Item ${index + 1}',
                    style: TextStyle(fontSize: 20),
                  ),
                );
              },
              childCount: 100,
            ),
          ),
        ],
      ),
    );
  }
}

ListTitle 编写用户中心栏目列表

使用 ListTile 来创建用户中心栏目列表，每一项包括一个图标、文字和右边的箭头符号：

dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  // 用户中心栏目数据
  final List<Map<String, dynamic>> userMenuItems = [
    {'icon': Icons.person, 'text': '个人资料'},
    {'icon': Icons.payment, 'text': '我的订单'},
    {'icon': Icons.favorite, 'text': '我的收藏'},
    {'icon': Icons.settings, 'text': '设置'},
  ];

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('User Center'),
        ),
        body: ListView.builder(
          itemCount: userMenuItems.length,
          itemBuilder: (context, index) {
            return Container(
              margin: EdgeInsets.symmetric(horizontal: 10.0, vertical: 5.0),
              child: ClipRRect(
                borderRadius: BorderRadius.circular(8.0), // 圆角边框
                child: Material(
                  color: themeC.themeColor['bgc-primary'],
                  child: InkWell(
                    onTap: () {
                      // 处理点击事件
                      print('You tapped on ${userMenuItems[index]['text']}');
                    },
                    child: ListTile(
                      leading: Icon(userMenuItems[index]['icon']),
                      title: Text(userMenuItems[index]['text']),
                      trailing: Icon(Icons.keyboard_arrow_right), // 右边箭头
                    ),
                  ),
                ),
              ),
            );
          },
        ),
      ),
    );
  }
}

TextButton ElevatedButton 等按钮尺寸大小

要设置 TextButton 的尺寸大小，你可以使用 ButtonStyle 中的 minimumSize 属性来指定按钮的最小尺寸。minimumSize 属性接受一个 Size 对象，表示按钮的最小宽度和高度。

dart

TextButton(
  onPressed: () {
    // 按钮点击事件
  },
  child: Text('TextButton'),
  style: ButtonStyle(
    minimumSize: MaterialStateProperty.all(Size(100.0, 50.0)), // 指定按钮的最小尺寸
  ),
)

ListView 循环，并且每项加背景和边框

要为 ListTile 添加背景颜色并在底部添加 1 像素的边框，你可以将 ListTile 包装在一个带有背景颜色和边框的 Container 中。以下是一个示例：

dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  final List<String> items = ['Item 1', 'Item 2', 'Item 3', 'Item 4', 'Item 5'];

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Array Loop Example'),
        ),
        body: ListView.builder(
          itemCount: items.length,
          itemBuilder: (context, index) {
            return Container(
              color: Colors.grey[200], // 设置背景颜色
              child: Column(
                children: [
                  ListTile(
                    title: Text(items[index]),
                  ),
                  Divider(
                    height: 1, // 设置分隔线高度
                    color: Colors.grey, // 设置分隔线颜色
                  ),
                ],
              ),
            );
          },
        ),
      ),
    );
  }
}

列表循环

通过判断条件输出不同的列表循环

dart


Container(
  constraints: const BoxConstraints(maxHeight: 200),
  child: SingleChildScrollView(
    physics: const AlwaysScrollableScrollPhysics(), // 允许内容滚动
    child: Wrap(
      spacing: 4,
      runSpacing: 10,
      children: type == 'normal'
          ? List.generate(4, (index) {
              return SizedBox(
                width: contentMaxWidth / 4 - 12,
                child: PrizeItem(),
              );
            }).toList()
          : List.generate(28, (index) {
              return SizedBox(
                width: contentMaxWidth / 4 - 12,
                child: PrizeItem(),
              );
            }).toList(),
    ),
  ),
),

InkWell 点击效果

需要放在 Material 里面

dart

Material(
    color: themeC.themeColor['bgc-primary'],
    child: InkWell(
      onTap: () {
        // 处理点击事件
        clickItem(userMenuItems[index]);
      },
      child: ListTile(
        contentPadding: const EdgeInsets.symmetric(horizontal: 12.0, vertical: 0.0),
        leading: Icon(userMenuItems[index]['icon']),
        title: Text(userMenuItems[index]['text']),
        trailing: Icon(Icons.keyboard_arrow_right), // 右边箭头
      ),
    ),
  ),

ScrollController 监听滚动到底部，加载更多数据

dart

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:pc28/components/empty.dart';
import '../../locales/locale_controller.dart';
import '../../themes/themes_controller.dart';
import '../../components/my_app_bar.dart';
import '../../api/api.dart';
import '../game/game_num.dart';

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

  @override
  State<Bill> createState() => _BillState();
}

class _BillState extends State<Bill> with SingleTickerProviderStateMixin {
  LocaleController localeC = Get.find<LocaleController>();
  ThemeController themeC = Get.find<ThemeController>();

  final ScrollController _scrollController = ScrollController();
  bool _isLoading = false;
  bool isLoaded = false;

  Map<String, dynamic> pageParams = {
    'page': 1,
    'limit': 20,
  };
  Map<String, dynamic> pageData = {
    'isNomore': false,
    'dataList': [],
  };

  void getData({bool? isMore, Function? callback}) async {
    final res = await apis['orderLog']!(pageParams);
    setState(() {
      isLoaded = true;
    });
    if (res['code'] == 1) {
      var resdata = res['data'] ?? {};
      if (resdata.isEmpty) return;
      if (isMore != null && !isMore) {
        if (mounted) {
          setState(() {
            pageData['dataList'] = resdata['data'];
          });
        }
      } else {
        if (mounted) {
          setState(() {
            pageData['dataList'] = [...pageData['dataList'], ...resdata['data']];
          });
        }
      }
      if (resdata['last_page'] > pageParams['page']) {
        setState(() {
          pageData['isNomore'] = false;
        });
      } else {
        setState(() {
          pageData['isNomore'] = true;
        });
      }
      if (callback != null) {
        callback();
      }
    }
  }

  @override
  void initState() {
    super.initState();
    _scrollController.addListener(_scrollListener);
    getData();
  }

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

  void _scrollListener() {
    if (_scrollController.position.pixels >= _scrollController.position.maxScrollExtent) {
      // 滚动到底部
      if (!pageData['isNomore']) {
        _loadMoreData();
      }
    }
  }

  void _loadMoreData() {
    if (!_isLoading) {
      setState(() {
        _isLoading = true;
        ++pageParams['page'];
      });
      getData(
        isMore: true,
        callback: () {
          setState(() {
            _isLoading = false;
          });
        },
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    String getNum(types, nums) {
      String betdata = '';
      List typesList = types.split(',');
      List<Map<String, dynamic>> bets = normalNumbs.where((item) => typesList.contains(item['type'].toString())).toList();
      betdata = bets.map((numb) => numb['name'] as String).join(', ');
      if (typesList.contains('5')) {
        betdata = betdata == '' ? nums : '$betdata,$nums';
      }
      return betdata;
    }

    // String getStatus(status) {
    //   String statusText = '';
    //   if (status == 1) {
    //     statusText = 'Won'.tr;
    //   } else if (status == 2) {
    //     statusText = 'Didn_win'.tr;
    //   } else {
    //     statusText = 'Not_drawn_yet'.tr;
    //   }
    //   return statusText;
    // }
    String getCheck(status) {
      String statusText = '';
      if (status == 1) {
        statusText = 'Drawn_result'.tr;
      } else {
        statusText = 'Not_drawn_yet'.tr;
      }
      return statusText;
    }

    // String getSign(status) {
    //   String signText = '';
    //   if (status == 1) {
    //     signText = '+';
    //   } else if (status == 2) {
    //     signText = '';
    //   } else {
    //     signText = '';
    //   }
    //   return signText;
    // }

    return Scaffold(
      appBar: MyAppBar(
        title: 'financial_bill'.tr, // 将字符串包装在Text小部件中
        backgroundColor: themeC.themeColor['bgc-primary'],
      ),
      body: Column(
        children: [
          Container(
            height: 46.0,
            color: themeC.themeColor['bgc-primary'],
            padding: const EdgeInsets.symmetric(horizontal: 8.0),
            child: Row(
              children: [
                Expanded(
                  flex: 1,
                  child: Center(
                    child: Text(
                      'Issue'.tr,
                      style: const TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 3,
                  child: Center(
                    child: Text(
                      'Betting_details'.tr,
                      style: const TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 1,
                  child: Center(
                    child: Text(
                      'state'.tr,
                      style: const TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 2,
                  child: Center(
                    child: Text(
                      'Profit_and_loss'.tr,
                      style: const TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
              ],
            ),
          ),
          isLoaded && pageData['dataList'].isEmpty
              ? const Expanded(child: Empty())
              : Expanded(
                  child: ListView.builder(
                    controller: _scrollController,
                    shrinkWrap: true, // 防止与SingleChildScrollView冲突
                    itemCount: pageData['dataList'].length + (_isLoading ? 1 : 0),
                    itemBuilder: (BuildContext content, int index) {
                      if (index < pageData['dataList'].length) {
                        var item = pageData['dataList'][index];
                        var betStr = getNum(item['buy_type'], item['buy_num']);
                        return Container(
                          margin: const EdgeInsets.symmetric(horizontal: 8.0),
                          padding: const EdgeInsets.symmetric(
                            vertical: 10.0,
                          ),
                          decoration: BoxDecoration(
                            border: Border(
                              bottom: BorderSide(
                                width: 1.0,
                                color: themeC.themeColor['bd-base']!,
                              ),
                            ),
                          ),
                          child: Row(
                            children: [
                              Expanded(
                                flex: 1,
                                child: Center(
                                  child: Text(
                                    '${item['code_sn']}',
                                    style: TextStyle(
                                      fontSize: 12.0,
                                      fontWeight: FontWeight.w700,
                                      color: themeC.themeColor['c-text-2'],
                                    ),
                                  ),
                                ),
                              ),
                              Expanded(
                                flex: 3,
                                child: Column(
                                  children: [
                                    RichText(
                                      textAlign: TextAlign.center,
                                      text: TextSpan(
                                          style: TextStyle(
                                            color: themeC.themeColor['c-text-3'],
                                          ),
                                          children: [
                                            TextSpan(
                                              text: '$betStr/',
                                              style: const TextStyle(
                                                fontSize: 10,
                                              ),
                                            ),
                                            TextSpan(
                                              text: '${item['buy_amount_one']}',
                                              style: TextStyle(
                                                color: themeC.themeColor['c-price'],
                                              ),
                                            ),
                                            const TextSpan(
                                              text: 'VND',
                                              style: TextStyle(
                                                fontSize: 11,
                                              ),
                                            ),
                                          ]),
                                    ),
                                    const SizedBox(
                                      height: 5,
                                    ),
                                    RichText(
                                      textAlign: TextAlign.center,
                                      text: TextSpan(
                                          style: TextStyle(
                                            color: themeC.themeColor['c-text-2'],
                                            fontWeight: FontWeight.w700,
                                          ),
                                          children: [
                                            TextSpan(
                                              text: '${'total'.tr}:',
                                              style: const TextStyle(
                                                fontSize: 10,
                                              ),
                                            ),
                                            TextSpan(
                                              text: '${item['buy_amount']}',
                                              style: TextStyle(
                                                color: themeC.themeColor['c-price'],
                                              ),
                                            ),
                                            const TextSpan(
                                              text: 'VND',
                                              style: TextStyle(
                                                fontSize: 11,
                                              ),
                                            ),
                                          ]),
                                    ),
                                  ],
                                ),
                              ),
                              Expanded(
                                flex: 1,
                                child: Center(
                                  child: Text(
                                    getCheck(item['is_check']),
                                    style: TextStyle(
                                      color: item['is_check'] == 1 ? themeC.themeColor['c-fall'] : themeC.themeColor['c-rise'],
                                    ),
                                  ),
                                ),
                              ),
                              Expanded(
                                flex: 2,
                                child: Center(
                                  child: Text(
                                    '${num.parse(item['earn_lost']) >= 0 ? '+' + item['earn_lost'] : item['earn_lost']}',
                                    style: TextStyle(
                                      color: num.parse(item['earn_lost']) >= 0 ? themeC.themeColor['c-fall'] : themeC.themeColor['c-rise'],
                                    ),
                                  ),
                                ),
                              ),
                            ],
                          ),
                        );
                      } else {
                        if (pageData['isNomore']) {
                          return const SizedBox();
                        } else {
                          return Padding(
                            padding: const EdgeInsets.symmetric(vertical: 16.0),
                            child: Center(
                              child: SizedBox(
                                width: 24,
                                height: 24,
                                child: CircularProgressIndicator(
                                  color: Colors.grey.withOpacity(0.5),
                                  strokeWidth: 3,
                                ),
                              ), // 加载指示器
                            ),
                          );
                        }
                      }
                    },
                  ),
                ),
        ],
      ),
    );
  }
}

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dart 数组操作

创建数组

使用 List 字面量创建数组

dart

List<int> numbers = [1, 2, 3, 4, 5];

使用 List 构造函数创建数组

dart

List<String> fruits = List<String>();
fruits.add('Apple');
fruits.add('Banana');
fruits.add('Orange');

获取数组长度

dart

List<int> numbers = [1, 2, 3, 4, 5];
int length = numbers.length;
print('Length of numbers: $length');

访问数组元素

dart

List<String> fruits = ['Apple', 'Banana', 'Orange'];
String firstFruit = fruits[0];
print('First fruit: $firstFruit');

添加元素到数组

dart

List<String> fruits = ['Apple', 'Banana', 'Orange'];
fruits.add('Mango');
print('Updated fruits: $fruits');

移除数组中的元素

dart

List<int> numbers = [1, 2, 3, 4, 5];
numbers.remove(3); // 移除元素 3
print('Updated numbers: $numbers');

遍历数组

使用 for 循环

dart

List<int> numbers = [1, 2, 3, 4, 5];
for (int i = 0; i < numbers.length; i++) {
  print('Element at index $i: ${numbers[i]}');
}

使用 forEach 方法

dart

List<String> fruits = ['Apple', 'Banana', 'Orange'];
fruits.forEach((fruit) {
  print('Fruit: $fruit');
});

转换数组

将数组转换为字符串

dart

List<String> fruits = ['Apple', 'Banana', 'Orange'];
String fruitsStr = fruits.join(', ');
print('Fruits: $fruitsStr');

将数组中的元素映射到新的数组

dart

List<int> numbers = [1, 2, 3, 4, 5];
List<String> numberStrs = numbers.map((number) => number.toString()).toList();
print('Number strings: $numberStrs');

检查数组是否包含某个元素

dart

List<String> fruits = ['Apple', 'Banana', 'Orange'];
bool containsBanana = fruits.contains('Banana');
print('Contains Banana? $containsBanana');

一个数组的某个标识包含另外一个数组的值

要判断 normalNumbs 列表中 type 字段的值是否在 [2, 3] 中，可以使用 where() 方法来过滤列表，然后使用 any() 方法来检查是否存在符合条件的元素。以下是示例代码：

dart

void main() {
  List<Map<String, dynamic>> normalNumbs = [
    {'type': 1, 'name': '大', 'rate': 'big_rate', 'check': false},
    {'type': 2, 'name': '小', 'rate': 'small_rate', 'check': false},
    {'type': 3, 'name': '单', 'rate': 'd_rate', 'check': false},
    {'type': 4, 'name': '双', 'rate': 's_rate', 'check': false}
  ];

  List<Map<String, dynamic>> filteredItems = normalNumbs.where((item) => [2, 3].contains(item['type'])).toList();

  print(filteredItems); // 输出包含指定类型的项目列表
}

在这个示例中，where() 方法将用于过滤列表，只保留 type 字段的值在 [2, 3] 中的元素。然后，isNotEmpty 属性将用于检查过滤后的列表是否包含任何元素，如果列表不为空，则表示 type 字段的值在 [2, 3] 中。

将数组的值复制到另一个数组

dart

List<int> originalList = [1, 2, 3, 4, 5];
List<int> copiedList = List<int>.from(originalList);
print('Copied list: $copiedList');

dart

List<Map<String, dynamic>> normalNumbs = [
  {'type': 1, 'name': '大', 'rate': 'big_rate', 'check': false},
  {'type': 2, 'name': '小', 'rate': 'small_rate', 'check': false},
  {'type': 3, 'name': '单', 'rate': 'd_rate', 'check': false},
  {'type': 4, 'name': '双', 'rate': 's_rate', 'check': false}
];
List<Map<String, dynamic>> normalList = List.from(normalNumbs.map((element) => {...element}));
List<Map<String, dynamic>> specialList = List.from(specialNumbs.map((element) => {...element}));

筛选数组中满足条件的元素

dart

List<int> numbers = [1, 2, 3, 4, 5];
List<int> evenNumbers = numbers.where((number) => number % 2 == 0).toList();
print('Even numbers: $evenNumbers');

对数组进行排序

dart

List<int> numbers = [5, 2, 8, 1, 3];
numbers.sort();
print('Sorted numbers: $numbers');

将数组拆分为多个部分

dart

List<int> numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
List<List<int>> chunks = [];
int chunkSize = 3;
for (int i = 0; i < numbers.length; i += chunkSize) {
  chunks.add(numbers.sublist(i, i + chunkSize));
}
print('Chunks: $chunks');

合并多个数组

dart

List<int> list1 = [1, 2, 3];
List<int> list2 = [4, 5, 6];
List<int> mergedList = [...list1, ...list2];
print('Merged list: $mergedList');

数组中的重复项计数

dart

List<int> numbers = [1, 2, 3, 2, 4, 3, 2, 5, 2];
Map<int, int> countMap = {};
numbers.forEach((number) {
  countMap[number] = (countMap[number] ?? 0) + 1;
});
print('Count map: $countMap');

扁平化多维数组

dart

List<List<int>> matrix = [
  [1, 2, 3],
  [4, 5],
  [6, 7, 8]
];
List<int> flatList = [];
matrix.forEach((row) {
  flatList.addAll(row);
});
print('Flat list: $flatList');

按条件分组数组元素

dart

List<int> numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
Map<bool, List<int>> groupedMap = numbers.groupBy((number) => number % 2 == 0);
print('Grouped map: $groupedMap');

转置矩阵

dart

List<List<int>> matrix = [
  [1, 2, 3],
  [4, 5, 6],
  [7, 8, 9]
];
List<List<int>> transposedMatrix = List.generate(matrix[0].length, (colIndex) {
  return List.generate(matrix.length, (rowIndex) => matrix[rowIndex][colIndex]);
});
print('Transposed matrix: $transposedMatrix');

滚动到底部触发加载更多

dart

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import '../../locales/locale_controller.dart';
import '../../themes/themes_controller.dart';
import '../../components/my_app_bar.dart';
import '../../api/api.dart';
import '../game/game_num.dart';

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

  @override
  State<Bill> createState() => _BillState();
}

class _BillState extends State<Bill> with SingleTickerProviderStateMixin {
  LocaleController localeC = Get.find<LocaleController>();
  ThemeController themeC = Get.find<ThemeController>();

  final ScrollController _scrollController = ScrollController();
  bool _isLoading = false;

  Map<String, dynamic> pageData = {
    'page': 1,
    'limit': 20,
    'isNomore': false,
    'dataList': [],
  };

  void getData({bool? isMore, Function? callback}) async {
    final res = await apis['orderLog']!(pageData);
    if (res['code'] == 1) {
      var resdata = res['data'] ?? {};
      if (resdata.isEmpty) return;
      if (isMore != null && !isMore) {
        if (mounted) {
          setState(() {
            pageData['dataList'] = resdata['data'];
          });
        }
      } else {
        if (mounted) {
          setState(() {
            pageData['dataList'] = [...pageData['dataList'], ...resdata['data']];
          });
        }
      }
      if (resdata['last_page'] > pageData['page']) {
        pageData['isNomore'] = false;
      } else {
        pageData['isNomore'] = true;
      }
      callback ?? ();
    }
  }

  @override
  void initState() {
    super.initState();
    _scrollController.addListener(_scrollListener);
    getData();
  }

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

  void _scrollListener() {
    if (_scrollController.position.pixels == _scrollController.position.maxScrollExtent) {
      // 滚动到底部
      if (!pageData['isNomore']) {
        _loadMoreData();
      }
    }
  }

  void _loadMoreData() {
    if (!_isLoading) {
      setState(() {
        _isLoading = true;
        ++pageData['page'];
      });
      getData(
        isMore: true,
        callback: () {
          _isLoading = false;
        },
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    String getNum(types, nums) {
      String betdata = '';
      List typesList = types.split(',');
      List<Map<String, dynamic>> bets = normalNumbs.where((item) => typesList.contains(item['type'].toString())).toList();
      betdata = bets.map((numb) => numb['name'] as String).join(', ');
      if (typesList.contains('5')) {
        betdata = betdata == '' ? nums : '$betdata,$nums';
      }
      return betdata;
    }

    String getStatus(status) {
      String statusText = '';
      if (status == 1) {
        statusText = '已中奖';
      } else if (status == 2) {
        statusText = '未中奖';
      } else {
        statusText = '未开奖';
      }
      return statusText;
    }

    String getSign(status) {
      String signText = '';
      if (status == 1) {
        signText = '+';
      } else if (status == 2) {
        signText = '-';
      } else {
        signText = '';
      }
      return signText;
    }

    return Scaffold(
      appBar: MyAppBar(
        title: '财务账单', // 将字符串包装在Text小部件中
        backgroundColor: themeC.themeColor['bgc-primary'],
      ),
      body: Column(
        children: [
          Container(
            height: 46.0,
            color: themeC.themeColor['bgc-primary'],
            padding: const EdgeInsets.symmetric(horizontal: 8.0),
            child: const Row(
              children: [
                Expanded(
                  flex: 1,
                  child: Center(
                    child: Text(
                      '期号',
                      style: TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 3,
                  child: Center(
                    child: Text(
                      '下注详情',
                      style: TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 1,
                  child: Center(
                    child: Text(
                      '状态',
                      style: TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
                Expanded(
                  flex: 2,
                  child: Center(
                    child: Text(
                      '盈亏',
                      style: TextStyle(
                        fontSize: 14.0,
                      ),
                    ),
                  ),
                ),
              ],
            ),
          ),
          Expanded(
            child: ListView.builder(
              controller: _scrollController,
              shrinkWrap: true, // 防止与SingleChildScrollView冲突
              itemCount: pageData['dataList'].length + (_isLoading ? 1 : 0),
              itemBuilder: (BuildContext content, int index) {
                if (index < pageData['dataList'].length) {
                  var item = pageData['dataList'][index];
                  var betStr = getNum(item['buy_type'], item['buy_num']);
                  return Container(
                    margin: const EdgeInsets.symmetric(horizontal: 8.0),
                    padding: const EdgeInsets.symmetric(
                      vertical: 10.0,
                    ),
                    decoration: BoxDecoration(
                      border: Border(
                        bottom: BorderSide(
                          width: 1.0,
                          color: themeC.themeColor['bd-base']!,
                        ),
                      ),
                    ),
                    child: Row(
                      children: [
                        Expanded(
                          flex: 1,
                          child: Center(
                            child: Text(
                              '${item['code_sn']}',
                              style: TextStyle(
                                fontSize: 12.0,
                                color: themeC.themeColor['c-text-3'],
                              ),
                            ),
                          ),
                        ),
                        Expanded(
                          flex: 3,
                          child: Center(
                            child: RichText(
                              text: TextSpan(
                                  style: TextStyle(
                                    color: themeC.themeColor['c-text-2'],
                                  ),
                                  children: [
                                    TextSpan(
                                      text: '$betStr/',
                                      style: const TextStyle(
                                        fontSize: 10,
                                      ),
                                    ),
                                    TextSpan(
                                      text: '${item['buy_amount_one']}',
                                      style: TextStyle(
                                        color: themeC.themeColor['c-price'],
                                      ),
                                    ),
                                    const TextSpan(
                                      text: 'VND',
                                      style: TextStyle(
                                        fontSize: 12,
                                      ),
                                    ),
                                  ]),
                            ),
                          ),
                        ),
                        Expanded(
                          flex: 1,
                          child: Center(
                            child: Text(
                              getStatus(item['status']),
                              style: TextStyle(
                                color: item['status'] == 1 ? themeC.themeColor['c-fall'] : themeC.themeColor['c-rise'],
                              ),
                            ),
                          ),
                        ),
                        Expanded(
                          flex: 2,
                          child: Center(
                            child: Text(
                              '${getSign(item['status'])}${item['earn_lost']}',
                              style: TextStyle(
                                color: item['status'] == 1 ? themeC.themeColor['c-fall'] : themeC.themeColor['c-rise'],
                              ),
                            ),
                          ),
                        ),
                      ],
                    ),
                  );
                } else {
                  if (pageData['isNomore']) {
                    return const SizedBox();
                  } else {
                    return Padding(
                      padding: const EdgeInsets.symmetric(vertical: 16.0),
                      child: Center(
                        child: SizedBox(
                          width: 24,
                          height: 24,
                          child: CircularProgressIndicator(
                            color: Colors.grey.withOpacity(0.5),
                            strokeWidth: 3,
                          ),
                        ), // 加载指示器
                      ),
                    );
                  }
                }
              },
            ),
          ),
        ],
      ),
    );
  }
}

判断 web 平台引入 dart:html 包

dart

import 'package:pc28/utils/file_to_base64.dart' if (dart.library.html) 'package:pc28/utils/file_to_base64_web.dart';

文字描边效果

dart

Stack(
  children: <Widget>[
    // 文字描边
    Text(
      '文字描边',
      style: TextStyle(
        fontSize: 20,
        fontWeight: FontWeight.w700,
        foreground: Paint()
          ..style = PaintingStyle.stroke
          ..strokeWidth = 4
          ..color = Colors.white,
      ),
    ),
    // 实际文字
    Text(
      '文字描边',
      style: const TextStyle(
        fontSize: 20,
        fontWeight: FontWeight.w700,
        color: Color(0xff0080DD), // 或者你想要的文字颜色
      ),
    ),
  ],
)

弹窗里面有列表切换，有表单操作

dart

void showBuy(BuildContext context) {
    showModalBottomSheet(
      isScrollControlled: true,
      isDismissible: true,
      elevation: 10.0,
      context: context,
      useSafeArea: true,
      shape: const RoundedRectangleBorder(
        borderRadius: BorderRadius.vertical(top: Radius.circular(0)),
      ),
      builder: (BuildContext context) {
        return StatefulBuilder(builder: (BuildContext context, StateSetter setState) {
          return SingleChildScrollView(
            child: LayoutBuilder(
              builder: (BuildContext context, BoxConstraints constraints) {
                double contentMaxWidth = constraints.maxWidth;
                return GestureDetector(
                  behavior: HitTestBehavior.translucent,
                  onTap: () {
                    FocusScope.of(context).requestFocus(FocusNode());
                  },
                  child: Container(
                    padding: const EdgeInsets.symmetric(vertical: 12.0, horizontal: 15.0),
                    child: Column(
                      children: [
                        Row(
                          children: [
                            Expanded(
                              flex: 1,
                              child: Center(
                                child: ElevatedButton(
                                  onPressed: () {
                                    setState(() {
                                      type = 'normal';
                                    });
                                  },
                                  style: ButtonStyle(
                                    backgroundColor: MaterialStatePropertyAll(type == 'normal' ? themeC.themeColor['c-second'] : themeC.themeColor['c-primary']),
                                    shape: MaterialStatePropertyAll(
                                      RoundedRectangleBorder(
                                        borderRadius: BorderRadius.circular(4.0),
                                      ),
                                    ),
                                  ),
                                  child: Text(
                                    'ordinary'.tr,
                                    style: const TextStyle(fontSize: 16.0),
                                  ),
                                ),
                              ),
                            ),
                            Expanded(
                              flex: 1,
                              child: Center(
                                child: ElevatedButton(
                                  onPressed: () {
                                    setState(() {
                                      type = 'special';
                                    });
                                  },
                                  style: ButtonStyle(
                                    backgroundColor: MaterialStatePropertyAll(type == 'special' ? themeC.themeColor['c-second'] : themeC.themeColor['c-primary']),
                                    shape: MaterialStatePropertyAll(
                                      RoundedRectangleBorder(
                                        borderRadius: BorderRadius.circular(4.0),
                                      ),
                                    ),
                                  ),
                                  child: Text(
                                    'special'.tr,
                                    style: const TextStyle(fontSize: 16.0),
                                  ),
                                ),
                              ),
                            ),
                          ],
                        ),
                        const Divider(
                          height: 14,
                          color: Colors.black26,
                        ),
                        Container(
                          constraints: const BoxConstraints(maxHeight: 200),
                          child: SingleChildScrollView(
                            physics: const AlwaysScrollableScrollPhysics(), // 允许内容滚动
                            child: Wrap(
                              spacing: 4,
                              runSpacing: 10,
                              children: type == 'normal'
                                  ? normalList.map((item) {
                                      int index = normalList.indexOf(item);
                                      return SizedBox(
                                        width: contentMaxWidth / 4 - 12,
                                        height: 28,
                                        child: Material(
                                          color: item['check'] ? themeC.themeColor['c-second'].withOpacity(0.8) : themeC.themeColor['bgc-primary'],
                                          borderRadius: BorderRadius.circular(4.0),
                                          child: InkWell(
                                            onTap: () {
                                              setState(() {
                                                normalList[index]['check'] = !normalList[index]['check'];
                                              });
                                            },
                                            child: PrizeItem(config: codeConfig, data: item),
                                          ),
                                        ),
                                      );
                                    }).toList()
                                  : specialList.map((item) {
                                      int index = specialList.indexOf(item);
                                      return SizedBox(
                                        width: contentMaxWidth / 4 - 12,
                                        height: 28,
                                        child: Material(
                                          color: item['check'] ? themeC.themeColor['c-second'].withOpacity(0.8) : themeC.themeColor['bgc-primary'],
                                          borderRadius: BorderRadius.circular(4.0),
                                          child: InkWell(
                                            onTap: () {
                                              setState(() {
                                                specialList[index]['check'] = !specialList[index]['check'];
                                              });
                                            },
                                            child: PrizeItem(config: codeConfig, data: item),
                                          ),
                                        ),
                                      );
                                    }).toList(),
                            ),
                          ),
                        ),
                        Padding(
                          padding: const EdgeInsets.only(top: 12, bottom: 12, left: 4, right: 4),
                          child: Wrap(
                            children: [
                              Container(
                                margin: const EdgeInsets.all(4),
                                height: 26,
                                decoration: BoxDecoration(
                                  border: Border.all(
                                    width: 1,
                                    color: themeC.themeColor['c-primary'],
                                  ),
                                  borderRadius: BorderRadius.circular(4),
                                ),
                                child: TextButton(
                                  onPressed: () {
                                    Get.toNamed('/rule');
                                  },
                                  child: Text('Rule_description'.tr),
                                ),
                              ),
                              Container(
                                margin: const EdgeInsets.all(4),
                                height: 26,
                                decoration: BoxDecoration(
                                  border: Border.all(
                                    width: 1,
                                    color: themeC.themeColor['c-primary'],
                                  ),
                                  borderRadius: BorderRadius.circular(4),
                                ),
                                child: TextButton(
                                  onPressed: () {
                                    rootC.changePageIndex(1);
                                    Get.toNamed('/root');
                                  },
                                  child: Text('Online_deposit'.tr),
                                ),
                              ),
                              Container(
                                margin: const EdgeInsets.all(4),
                                height: 26,
                                decoration: BoxDecoration(
                                  border: Border.all(
                                    width: 1,
                                    color: themeC.themeColor['c-primary'],
                                  ),
                                  borderRadius: BorderRadius.circular(4),
                                ),
                                child: TextButton(
                                  onPressed: () {
                                    Get.toNamed('/withdraw');
                                  },
                                  child: Text('Quick_cash_withdrawal'.tr),
                                ),
                              ),
                              Container(
                                margin: const EdgeInsets.all(4),
                                height: 26,
                                decoration: BoxDecoration(
                                  border: Border.all(
                                    width: 1,
                                    color: themeC.themeColor['c-primary'],
                                  ),
                                  borderRadius: BorderRadius.circular(4),
                                ),
                                child: TextButton(
                                  onPressed: () {
                                    Get.toNamed('/bill');
                                  },
                                  child: Text('Betting_records'.tr),
                                ),
                              ),
                            ],
                          ),
                        ),
                        Row(
                          children: [
                            Text('${'Buy_points'.tr}：'),
                            Expanded(
                              child: Container(
                                  height: 40.0,
                                  padding: const EdgeInsets.symmetric(horizontal: 6.0),
                                  child: MyTextfield(
                                    maxLength: 10,
                                    backgroundColor: Colors.white,
                                    keyboardType: ITextInputType.number,
                                    hintText: 'Please_enter_purchase_points'.tr,
                                    controlCallBack: (control) {
                                      numControl = control;
                                    },
                                    fieldCallBack: (val) {
                                      formData['buy_amount_one'] = val;
                                    },
                                  )),
                            ),
                            ElevatedButton(
                              onPressed: () {
                                buyOrder(context);
                              },
                              style: ButtonStyle(
                                backgroundColor: MaterialStatePropertyAll(themeC.themeColor['c-second']),
                                shape: MaterialStatePropertyAll(
                                  RoundedRectangleBorder(
                                    borderRadius: BorderRadius.circular(4.0),
                                  ),
                                ),
                              ),
                              child: Text('Buy'.tr),
                            ),
                          ],
                        ),
                      ],
                    ),
                  ),
                );
              },
            ),
          );
        });
      },
    );
  }
}

点击展开收缩图片旋转动画

dart


bool _isExpanded = false;

TweenAnimationBuilder(
  duration: const Duration(milliseconds: 300),
  tween: Tween<double>(begin: _isExpanded ? -1 : 0.0, end: _isExpanded ? 1.0 : 0.0),
  builder: (context, double value, child) {
    return Transform.rotate(
      angle: value * -1.0 * 3.14,
      child: const MyImage(
        url: 'assets/images/icon_arrow_down.png',
        width: 18,
        height: 18,
      ),
    );
  },
)

多颜色渐变列表

dart

import 'package:flutter/material.dart';
import 'package:flutter_easyloading/flutter_easyloading.dart';
import 'package:get/get.dart';
import 'package:pc28/components/my_app_bar.dart';
import '../../api/api.dart';
import '../../auth/auth_controller.dart';

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

  @override
  State<Room> createState() => _RoomState();
}

class _RoomState extends State<Room> {
  AuthController authC = Get.find<AuthController>();

  List listColors = [
    [const Color(0xff7B8DB1), const Color(0xff748DB2), const Color(0xff8B8DCA)],
    [const Color(0xffE59343), const Color(0xffF09C39), const Color(0xffFF7E36)],
    [const Color(0xffF3C095), const Color(0xffDC7E79), const Color(0xffEAA9CB)],
    [const Color(0xffE0E0FB), const Color(0xffC5CDF5), const Color(0xffF6D3DA)],
  ];
  List listImgs = [
    'assets/images/room_1.png',
    'assets/images/room_2.png',
    'assets/images/room_3.png',
    'assets/images/room_4.png',
  ];

  List list = [];
  void getRoomList() async {
    final res = await apis['colorsCodeConfig']!(<String, dynamic>{});
    if (res['code'] == 1) {
      setState(() {
        list = res['data'] ?? [];
      });
    }
  }

  void toGame(data) {
    if (num.parse(data['min_one']) > num.parse(authC.userinfo['money'])) {
      EasyLoading.showToast('${'The_balance_cannot_be_less_than'.tr} ${data['min_one']}');
      return;
    }
    Get.toNamed(
      '/game',
      arguments: data,
    );
  }

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

  List<Widget> getRooms() {
    List<Widget> rooms = [];
    for (var i = 0; i < list.length; i++) {
      rooms.add(Container(
        margin: const EdgeInsets.symmetric(vertical: 6.0),
        padding: const EdgeInsets.only(top: 45.0, left: 30.0),
        width: double.maxFinite,
        height: 150.0,
        decoration: BoxDecoration(
          image: DecorationImage(
            image: AssetImage(listImgs[i % 4]),
            fit: BoxFit.fill,
          ),
        ),
        child: InkWell(
          onTap: () {
            toGame(list[i]);
          },
          highlightColor: Colors.transparent,
          splashColor: Colors.transparent,
          child: ShaderMask(
            shaderCallback: (Rect bounds) {
              return LinearGradient(
                begin: Alignment.centerLeft,
                end: Alignment.centerRight,
                colors: listColors[i % 4],
                tileMode: TileMode.mirror,
              ).createShader(bounds);
            },
            child: Text(
              list[i]['colors_name'],
              style: const TextStyle(
                fontSize: 20,
                fontWeight: FontWeight.w700,
                color: Colors.white, // 或者你想要的文字颜色
              ),
            ),
          ),
        ),
      ));
    }
    return rooms;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: MyAppBar(
        title: 'Select_room'.tr,
      ),
      body: SingleChildScrollView(
        child: Padding(
          padding: const EdgeInsets.only(top: 6.0, left: 16.0, right: 16.0, bottom: 6.0),
          child: Column(
            children: getRooms(),
          ),
        ),
      ),
    );
  }
}

flutter 常用代码片段 ​

表格 ​

appBar 下面添加内容，并且悬浮 ​

ListTitle 编写用户中心栏目列表 ​

TextButton ElevatedButton 等按钮尺寸大小 ​

ListView 循环，并且每项加背景和边框 ​

列表循环 ​

InkWell 点击效果 ​

ScrollController 监听滚动到底部，加载更多数据 ​

dart 数组操作 ​

创建数组 ​

获取数组长度 ​

访问数组元素 ​

添加元素到数组 ​

移除数组中的元素 ​

遍历数组 ​

转换数组 ​

检查数组是否包含某个元素 ​

一个数组的某个标识包含另外一个数组的值 ​

将数组的值复制到另一个数组 ​

筛选数组中满足条件的元素 ​

对数组进行排序 ​

将数组拆分为多个部分 ​

合并多个数组 ​

数组中的重复项计数 ​

扁平化多维数组 ​

按条件分组数组元素 ​

转置矩阵 ​

滚动到底部触发加载更多 ​

判断 web 平台引入 dart:html 包 ​

文字描边效果 ​

弹窗里面有列表切换，有表单操作 ​

点击展开收缩图片旋转动画 ​

多颜色渐变列表 ​

flutter 常用代码片段

表格

appBar 下面添加内容，并且悬浮

ListTitle 编写用户中心栏目列表

TextButton ElevatedButton 等按钮尺寸大小

ListView 循环，并且每项加背景和边框

列表循环

InkWell 点击效果

ScrollController 监听滚动到底部，加载更多数据

dart 数组操作

创建数组

获取数组长度

访问数组元素

添加元素到数组

移除数组中的元素

遍历数组

转换数组

检查数组是否包含某个元素

一个数组的某个标识包含另外一个数组的值

将数组的值复制到另一个数组

筛选数组中满足条件的元素

对数组进行排序

将数组拆分为多个部分

合并多个数组

数组中的重复项计数

扁平化多维数组

按条件分组数组元素

转置矩阵

滚动到底部触发加载更多

判断 web 平台引入 dart:html 包

文字描边效果

弹窗里面有列表切换，有表单操作

点击展开收缩图片旋转动画

多颜色渐变列表