Flutter：自定义Tab切换，订单列表页tab，tab吸顶

1、自定义tab切换

view

<Widget>[// 好评<Widget>[TDImage(assetUrl: 'assets/img/order4.png',width: 36.w,height: 36.w,),SizedBox(width: 10.w,),TextWidget.body('好评',size: 24.sp,color: controller.tabIndex == 0 ? AppTheme.colorfff : AppTheme.color999,),].toRow(mainAxisAlignment: MainAxisAlignment.center).card(color: controller.tabIndex == 0 ? AppTheme.error : AppTheme.colorfff,shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10.w))).tight(width: 160.w,height: 68.w).onTap(() {controller.onTapOrderStatus(0);}),SizedBox(width: 20.w,),// 中评<Widget>[TDImage(assetUrl: 'assets/img/order5.png',width: 36.w,height: 36.w,),SizedBox(width: 10.w,),TextWidget.body('中评',size: 24.sp,color: controller.tabIndex == 1 ? AppTheme.colorfff : AppTheme.color999,),].toRow(mainAxisAlignment: MainAxisAlignment.center).card(color: controller.tabIndex == 1 ? AppTheme.error : AppTheme.colorfff,shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10.w))).tight(width: 160.w,height: 68.w).onTap(() {controller.onTapOrderStatus(1);}),SizedBox(width: 20.w,),// 差评<Widget>[TDImage(assetUrl: 'assets/img/order6.png',width: 36.w,height: 36.w,),SizedBox(width: 10.w,),TextWidget.body('差评',size: 24.sp,color: controller.tabIndex == 2 ? AppTheme.colorfff : AppTheme.color999,),].toRow(mainAxisAlignment: MainAxisAlignment.center).card(color: controller.tabIndex == 2 ? AppTheme.error : AppTheme.colorfff,shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10.w))).tight(width: 160.w,height: 68.w).onTap(() {controller.onTapOrderStatus(2);}),
].toRow(),

controller

import 'package:flutter/material.dart';
import 'package:get/get.dart';
class OrderEvaluateController extends GetxController{OrderEvaluateController();// tab 索引int tabIndex = 0;// 状态改变onTapOrderStatus(int index){tabIndex = index;// print('tabIndex: $tabIndex');update(["order_evaluate"]);}@overridevoid onClose() {super.onClose();tabController.dispose();}
}

2、订单列表tab，可以指定tabIndex的初始位置

view

import 'package:demo/common/index.dart';
import 'package:ducafe_ui_core/ducafe_ui_core.dart';
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:pull_to_refresh_flutter3/pull_to_refresh_flutter3.dart';
import 'package:tdesign_flutter/tdesign_flutter.dart';
import 'index.dart';class OrderListPage extends GetView<OrderListController> {const OrderListPage({super.key});// tab切换Widget _buildTab() {return TDTabBar(controller: controller.tabController,tabs: controller.tabNames.map((e) => TDTab(text: e)).toList(),onTap: (index) {controller.onTapOrderStatus(index);},backgroundColor: Colors.white,showIndicator: true,indicatorColor: const Color(0xffe01e1e),labelColor: const Color(0xffe01e1e),);}// list 列表Widget _buildList() {return SmartRefresher(controller: controller.refreshController,enablePullUp: true, // 启用上拉加载onRefresh: controller.onRefresh, // 下拉刷新回调onLoading: controller.onLoading, // 上拉加载回调footer: const SmartRefresherFooterWidget(), // 底部加载更多组件header: const SmartRefresherHeaderWidget(), // 顶部下拉刷新组件child: ListView.builder(itemCount: 10,itemBuilder: (context, index) {return _buildItem();},),);}// 商品itemWidget _buildItem() {return Text('item')}// 主视图Widget _buildView() {return <Widget>[_buildTab(),Expanded(child: _buildList()),].toColumn();}@overrideWidget build(BuildContext context) {return GetBuilder<OrderListController>(init: OrderListController(),id: "order_list",builder: (_) {return Scaffold(backgroundColor: const Color(0xffF5F6FA),appBar: const TDNavBar(height: 45,title: '我的订单',titleFontWeight: FontWeight.w600,backgroundColor: Colors.white,screenAdaptation: true,useDefaultBack: true,),body: SafeArea(child: _buildView(),),);},);}
}

controller

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:pull_to_refresh_flutter3/pull_to_refresh_flutter3.dart';class OrderListController extends GetxController with GetSingleTickerProviderStateMixin{OrderListController();// 订单列表List items = [];// tab 控制器late TabController tabController;// tab 索引int tabIndex = Get.arguments["tabIndex"] ?? 0;// tab 名称List<String> tabNames = ['全部', '待付款', '待发货', '待收货', '已完成'];// 订单状态改变onTapOrderStatus(int index){tabIndex = index;// 刷新订单列表refreshController.requestRefresh();update(["order_list"]);}@overridevoid onInit() {super.onInit();// 初始化时设置当前索引tabController = TabController(length: tabNames.length,vsync: this,initialIndex: tabIndex, // 设置初始索引);// 监听 tab 切换tabController.addListener(() {if (tabController.indexIsChanging) {tabIndex = tabController.index;update(["order_list"]);}});}@overridevoid onClose() {super.onClose();refreshController.dispose();tabController.dispose();}/** 分页* refreshController：分页控制器* _page：分页* _limit：每页条数* _loadNewsSell:拉取数据（是否刷新）* onLoading：上拉加载新商品* onRefresh：下拉刷新* */final RefreshController refreshController = RefreshController(initialRefresh: true,);// int _page = 1;// int _limit = 20;Future<bool> _loadNewsSell(bool isRefresh) async {return false;// var result = await ProductApi.products(ProductsReq(//   page:isRefresh ? 1:_page,//     prePage:_limit// ));// if(isRefresh){//   _page = 1;//   items.clear();// }// if(result.isNotEmpty){//   _page++;//   items.addAll(result);// }// // 是否是空// return result.isEmpty;}// 上拉载入新商品void onLoading() async {if (items.isNotEmpty) {try {// 拉取数据是否为空 ? 设置暂无数据 ： 加载完成var isEmpty = await _loadNewsSell(false);isEmpty? refreshController.loadNoData(): refreshController.loadComplete();} catch (e) {refreshController.loadFailed(); // 加载失败}} else {refreshController.loadNoData(); // 设置无数据}update(["goods_list"]);}// 下拉刷新void onRefresh() async {try {await _loadNewsSell(true);refreshController.refreshCompleted();} catch (e) {refreshController.refreshFailed();}update(["goods_list"]);}
}

3、tab吸顶，主要记录view中的实现。
下拉刷新和tab切换的方法基本与上方2、的controller一致

view

import 'package:ducafe_ui_core/ducafe_ui_core.dart';
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:pull_to_refresh_flutter3/pull_to_refresh_flutter3.dart';
import 'package:tdesign_flutter/tdesign_flutter.dart';
import 'package:xiaoshukeji/common/index.dart';
import 'index.dart';// 1. SliverPersistentHeaderDelegate：必须实现的抽象类
class _StickyTabBarDelegate extends SliverPersistentHeaderDelegate {final Widget child;_StickyTabBarDelegate({required this.child});@overrideWidget build(BuildContext context, double shrinkOffset, bool overlapsContent) {// shrinkOffset: 滚动距离// overlapsContent: 是否与其他内容重叠return Container(color: AppTheme.pageBgColor,child: child,);}@overridedouble get maxExtent => 92.w; // 最大高度，已知tab高度72+上下padding：10@overridedouble get minExtent => 92.w; // 最小高度@overridebool shouldRebuild(covariant SliverPersistentHeaderDelegate oldDelegate) => true;
}class RankingPage extends GetView<RankingController> {const RankingPage({super.key});// 头部皇冠位置Widget _buildHeader() {return <Widget>[].toRow().card(color: AppTheme.pageBgColor).tight(width: 750.w,height: 300.w,);}// tab，可吸顶Widget _buildTab() {return <Widget>[<Widget>[TextWidget.body('日榜', size: 28.sp, weight: FontWeight.w600, color: AppTheme.textColorfff),].toRow(mainAxisAlignment: MainAxisAlignment.center).card(color: AppTheme.primaryYellow).tight(width: 336.w,height: 72.w,),<Widget>[TextWidget.body('总榜', size: 28.sp, weight: FontWeight.w600, color: AppTheme.textColor6a7),].toRow(mainAxisAlignment: MainAxisAlignment.center).card(color: AppTheme.navBarBgColor).tight(width: 336.w,height: 72.w,),].toRow(mainAxisAlignment: MainAxisAlignment.spaceBetween);}// 数据列表Widget _buildDataList() {return SliverList(delegate: SliverChildBuilderDelegate((context, index) {return <Widget>[].toRow().paddingHorizontal(30.w).card(color: AppTheme.blockBgColor).tight(width: 690.w,height: 120.w,).marginOnly(bottom: 20.w);},childCount: 20,),);}// 主视图Widget _buildView() {return SmartRefresher(controller: controller.refreshController,enablePullUp: true,onRefresh: controller.onRefresh,onLoading: controller.onLoading,footer: const SmartRefresherFooterWidget(),header: const SmartRefresherHeaderWidget(),child: CustomScrollView(slivers: [// 头部_buildHeader().sliverToBoxAdapter().sliverPaddingHorizontal(30.w),// 2. SliverPersistentHeader：实现吸顶的核心组件SliverPersistentHeader(pinned: true,  // 设置为 true 实现吸顶delegate: _StickyTabBarDelegate(child: Container(padding: EdgeInsets.symmetric(horizontal: 30.w, vertical: 10.w),child: _buildTab(),),),),// 列表内容_buildDataList().sliverPaddingHorizontal(30.w),],),);}@overrideWidget build(BuildContext context) {return GetBuilder<RankingController>(init: RankingController(),id: "ranking",builder: (_) {return Scaffold(backgroundColor: AppTheme.pageBgColor, // 自定义颜色appBar: const TDNavBar(height: 0,titleColor: AppTheme.textColorfff,titleFontWeight: FontWeight.w600,backgroundColor: AppTheme.pageBgColor,screenAdaptation: true, // 是否进行屏幕适配，默认trueuseDefaultBack: false,),body: _buildView(),);},);}
}

GetTickerProviderStateMixin 和 GetSingleTickerProviderStateMixin 的主要区别在于：
1、GetSingleTickerProviderStateMixin:
用于创建单个 AnimationController
性能更好，因为只维护一个 Ticker
适用场景：只需要一个动画控制器的情况，如单个 TabController
class MyController extends GetxController with GetSingleTickerProviderStateMixin {late TabController tabController;@overridevoid onInit() {super.onInit();tabController = TabController(length: 3, vsync: this);}@overridevoid onClose() {tabController.dispose();super.onClose();}
}2、GetTickerProviderStateMixin:
可以创建多个 AnimationController
适用场景：需要多个独立动画控制器的情况class MyController extends GetxController with GetTickerProviderStateMixin {late AnimationController controller1;late AnimationController controller2;@overridevoid onInit() {super.onInit();controller1 = AnimationController(vsync: this,duration: const Duration(milliseconds: 300),);controller2 = AnimationController(vsync: this,duration: const Duration(milliseconds: 500),);}
}什么时候需要 GetSingleTickerProviderStateMixin：
当你使用 TabController 来控制 tab 切换动画
当你需要实现滑动切换 tab 功能
当你需要更复杂的 tab 切换效果如果只需要点击切换，不需要 GetSingleTickerProviderStateMixin