uview-plus中二级菜单左右联动更改为uni-app+vue3+vite写法

uview-plus3.0重磅发布，全面的Vue3移动组件库

该插件使用的vue2写法，但支持vue3引用，在此基础上修改为uni-app+vue3+vite;

<template>
	<view class="u-wrap mainClass">
		<!-- <back-header :title="pageTitle" :back-text="backText"></back-header> -->
		<view class="u-search-box">
				<view class="u-search-inner">
				<u-icon name="search" color="#909399" :size="28"></u-icon>
				<text class="u-search-text">搜索</text>
			</view>
		</view>
		<view class="u-menu-wrap">
			<scroll-view scroll-y scroll-with-animation class="u-tab-view menu-scroll-view" :scroll-top="scrollTop"
				:scroll-into-view="itemId">
				<view v-for="(item,index) in tabbar" :key="index" class="u-tab-item"
					:class="[current == index ? 'u-tab-item-active' : '']" @tap.stop="swichMenu(index)">
					<text class="u-line-1">{{item.name}}</text>
				</view>
			</scroll-view>
			<scroll-view :scroll-top="scrollRightTop" scroll-y scroll-with-animation class="right-box"
				@scroll="rightScroll">
				<view class="page-view">
					<view class="class-item" :id="'item' + index" v-for="(item , index) in tabbar" :key="index">
						<view class="item-title">
							<text>{{item.name}}</text>
						</view>
						<view class="item-container">
							<view class="thumb-box" v-for="(item1, index1) in item.foods" :key="index1">
								<image class="item-menu-image" :src="item1.icon" mode=""></image>
								<view class="item-menu-name">{{item1.name}}</view>
							</view>
						</view>
					</view>
				</view>
			</scroll-view>
		</view>
	</view>
</template>
<script lang="ts" setup>
	// import BackHeader from '../../../components/publicNavbar.vue';
	import { defineComponent, ref, onMounted, onBeforeUnmount, getCurrentInstance } from 'vue';
	import classifyData from '@/common/classify.data.js';

	const scrollTop = ref(0);
	const oldScrollTop = ref(0);
	const current = ref(0);
	const menuHeight = ref(0);
	const menuItemHeight = ref(0);
	const itemId = ref('');
	const tabbar = classifyData;
	const menuItemPos = ref([]);
	const arr = ref([]);
	const scrollRightTop = ref(0);
	let timer : NodeJS.Timeout | null = null;
	const pageTitle = ref('商品')
	const backText = ref('')

	const instance = getCurrentInstance();

	onMounted(() => {
		getMenuItemTop();
	});

	const swichMenu = async (index : number) => {
		if (arr.value.length === 0) {
			await getMenuItemTop();
		}
		if (index === current.value) return;
		scrollRightTop.value = oldScrollTop.value;
		// 异步更新后使用 nextTick 确保能够正确获取最新的 DOM
		await new Promise<void>((resolve) => {
			setTimeout(() => {
				scrollRightTop.value = arr.value[index];
				current.value = index;
				leftMenuStatus(index);
				resolve();
			}, 0);
		});
	};

	const getElRect = (elClass : string, dataVal : string) => {
		const query = uni.createSelectorQuery().in(instance);
		query.select('.' + elClass).boundingClientRect((res) => {
			if (!res) {
				setTimeout(() => {
					getElRect(elClass, dataVal);
				}, 10);
				return;
			}
			instance.ctx[dataVal] = res.height;
		}).exec();
	};

	const observer = () => {
		tabbar.forEach((val, index) => {
			let observer = uni.createIntersectionObserver(this);
			observer.relativeTo('.right-box', { top: 0 }).observe('#item' + index, (res) => {
				if (res.intersectionRatio > 0) {
					let id = Number(res.id.substring(4));
					leftMenuStatus(id);
				}
			});
		});
	};

	const leftMenuStatus = (index : number) => {
		current.value = index;
		if (menuHeight.value == 0 || menuItemHeight.value == 0) {
			getElRect('menu-scroll-view', 'menuHeight');
			getElRect('u-tab-item', 'menuItemHeight');
		}
		scrollTop.value = index * menuItemHeight.value + menuItemHeight.value / 2 - menuHeight.value / 2;
	};

	const getMenuItemTop = () => {
		let selectorQuery = uni.createSelectorQuery();
		selectorQuery.selectAll('.class-item').boundingClientRect((rects) => {
			if (!rects.length) {
				setTimeout(() => {
					getMenuItemTop();
				}, 10);
				return;
			}
			rects.forEach((rect, index) => {
				arr.value.push(rect.top - rects[0].top);
			});
		}).exec();
	};

	const rightScroll = async (e : any) => {
		oldScrollTop.value = e.detail.scrollTop;
		if (arr.value.length === 0) {
			await getMenuItemTop();
		}
		if (timer) return;
		if (!menuHeight.value) {
			getElRect('menu-scroll-view', 'menuHeight');
		}
		setTimeout(() => {
			timer = null;
			let scrollHeight = e.detail.scrollTop + menuHeight.value / 2;
			for (let i = 0; i < arr.value.length; i++) {
				let height1 = arr.value[i];
				let height2 = arr.value[i + 1];
				if (!height2 || (scrollHeight >= height1 && scrollHeight < height2)) {
					leftMenuStatus(i);
					return;
				}
			}
		}, 10);
	};

	onBeforeUnmount(() => {
		if (timer) clearTimeout(timer);
	});
</script>

<style lang="scss" scoped>
	.u-wrap {
		height: calc(100vh);
		/* #ifdef H5 */
		height: calc(100vh - var(--window-top));
		/* #endif */
		display: flex;
		flex-direction: column;
	}

	.u-search-box {
		padding: 18rpx 30rpx;
	}

	.u-menu-wrap {
		flex: 1;
		display: flex;
		overflow: hidden;
	}

	.u-search-inner {
		background-color: rgb(234, 234, 234);
		border-radius: 100rpx;
		display: flex;
		align-items: center;
		padding: 10rpx 16rpx;
	}

	.u-search-text {
		font-size: 26rpx;
		color: $u-tips-color;
		margin-left: 10rpx;
	}

	.u-tab-view {
		width: 200rpx;
		height: 100%;
	}

	.u-tab-item {
		height: 110rpx;
		background: #f6f6f6;
		box-sizing: border-box;
		display: flex;
		align-items: center;
		justify-content: center;
		font-size: 26rpx;
		color: #444;
		font-weight: 400;
		line-height: 1;
	}

	.u-tab-item-active {
		position: relative;
		color: #000;
		font-size: 30rpx;
		font-weight: 600;
		background: #fff;
	}

	.u-tab-item-active::before {
		content: "";
		position: absolute;
		border-left: 4px solid $u-primary;
		height: 32rpx;
		left: 0;
		top: 39rpx;
	}

	.u-tab-view {
		height: 100%;
	}

	.right-box {
		background-color: rgb(250, 250, 250);
	}

	.page-view {
		padding: 16rpx;
	}

	.class-item {
		margin-bottom: 30rpx;
		background-color: #fff;
		padding: 16rpx;
		border-radius: 8rpx;
	}

	.class-item:last-child {
		min-height: 100vh;
	}

	.item-title {
		font-size: 26rpx;
		color: $u-main-color;
		font-weight: bold;
	}

	.item-menu-name {
		font-weight: normal;
		font-size: 24rpx;
		color: $u-main-color;
	}

	.item-container {
		display: flex;
		flex-wrap: wrap;
	}

	.thumb-box {
		width: 33.333333%;
		display: flex;
		align-items: center;
		justify-content: center;
		flex-direction: column;
		margin-top: 20rpx;
	}

	.item-menu-image {
		width: 120rpx;
		height: 120rpx;
	}
</style>