| <template> | 
|     <view class="u-index-list"> | 
|         <!-- #ifdef APP-NVUE --> | 
|         <list | 
|             :scrollTop="scrollTop" | 
|             enable-back-to-top | 
|             :offset-accuracy="1" | 
|             :style="{ | 
|                 maxHeight: $u.addUnit(scrollViewHeight) | 
|             }" | 
|             @scroll="scrollHandler" | 
|             ref="uList" | 
|         > | 
|             <cell | 
|                 v-if="$slots.header" | 
|                 ref="header" | 
|             > | 
|                 <slot name="header" /> | 
|             </cell> | 
|             <slot /> | 
|             <cell v-if="$slots.footer"> | 
|                 <slot name="footer" /> | 
|             </cell> | 
|         </list> | 
|         <!-- #endif --> | 
|         <!-- #ifndef APP-NVUE --> | 
|         <scroll-view | 
|             :scrollTop="scrollTop" | 
|             :scrollIntoView="scrollIntoView" | 
|             :offset-accuracy="1" | 
|             :style="{ | 
|                 maxHeight: $u.addUnit(scrollViewHeight) | 
|             }" | 
|             scroll-y | 
|             @scroll="scrollHandler" | 
|             ref="uList" | 
|         > | 
|             <view v-if="$slots.header"> | 
|                 <slot name="header" /> | 
|             </view> | 
|             <slot /> | 
|             <view v-if="$slots.footer"> | 
|                 <slot name="footer" /> | 
|             </view> | 
|         </scroll-view> | 
|         <!-- #endif --> | 
|         <view | 
|             class="u-index-list__letter" | 
|             ref="u-index-list__letter" | 
|             :style="{ top: $u.addUnit(letterInfo.top || 100) }" | 
|             @touchstart="touchStart" | 
|             @touchmove.stop.prevent="touchMove" | 
|             @touchend.stop.prevent="touchEnd" | 
|             @touchcancel.stop.prevent="touchEnd" | 
|         > | 
|             <view | 
|                 class="u-index-list__letter__item" | 
|                 v-for="(item, index) in uIndexList" | 
|                 :key="index" | 
|                 :style="{ | 
|                     backgroundColor: activeIndex === index ? activeColor : 'transparent' | 
|                 }" | 
|             > | 
|                 <text | 
|                     class="u-index-list__letter__item__index" | 
|                     :style="{color: activeIndex === index ? '#fff' : inactiveColor}" | 
|                 >{{ item }}</text> | 
|             </view> | 
|         </view> | 
|         <u-transition | 
|             mode="fade" | 
|             :show="touching" | 
|             :customStyle="{ | 
|                 position: 'fixed', | 
|                 right: '50px', | 
|                 top: $u.addUnit(indicatorTop), | 
|                 zIndex: 2 | 
|             }" | 
|         > | 
|             <view | 
|                 class="u-index-list__indicator" | 
|                 :class="['u-index-list__indicator--show']" | 
|                 :style="{ | 
|                     height: $u.addUnit(indicatorHeight), | 
|                     width: $u.addUnit(indicatorHeight) | 
|                 }" | 
|             > | 
|                 <text class="u-index-list__indicator__text">{{ uIndexList[activeIndex] }}</text> | 
|             </view> | 
|         </u-transition> | 
|     </view> | 
| </template> | 
|   | 
| <script> | 
|     const indexList = () => { | 
|         const indexList = []; | 
|         const charCodeOfA = 'A'.charCodeAt(0); | 
|         for (let i = 0; i < 26; i++) { | 
|             indexList.push(String.fromCharCode(charCodeOfA + i)); | 
|         } | 
|         return indexList; | 
|     } | 
|     import props from './props.js'; | 
|     // #ifdef APP-NVUE | 
|     // 由于weex为阿里的KPI业绩考核的产物,所以不支持百分比单位,这里需要通过dom查询组件的宽度 | 
|     const dom = uni.requireNativePlugin('dom') | 
|     // #endif | 
|     /** | 
|      * IndexList 索引列表 | 
|      * @description  通过折叠面板收纳内容区域 | 
|      * @tutorial https://uviewui.com/components/indexList.html | 
|      * @property {String}            inactiveColor    右边锚点非激活的颜色 ( 默认 '#606266' ) | 
|      * @property {String}            activeColor        右边锚点激活的颜色 ( 默认 '#5677fc' ) | 
|      * @property {Array}            indexList        索引字符列表,数组形式 | 
|      * @property {Boolean}            sticky            是否开启锚点自动吸顶 ( 默认 true ) | 
|      * @property {String | Number}    customNavHeight    自定义导航栏的高度 ( 默认 0 ) | 
|      * */  | 
|     export default { | 
|         name: 'u-index-list', | 
|         mixins: [uni.$u.mpMixin, uni.$u.mixin, props], | 
|         // #ifdef MP-WEIXIN | 
|         // 将自定义节点设置成虚拟的,更加接近Vue组件的表现,能更好的使用flex属性 | 
|         options: { | 
|             virtualHost: true | 
|         }, | 
|         // #endif | 
|         data() { | 
|             return { | 
|                 // 当前正在被选中的字母索引 | 
|                 activeIndex: -1, | 
|                 touchmoveIndex: 1, | 
|                 // 索引字母的信息 | 
|                 letterInfo: { | 
|                     height: 0, | 
|                     itemHeight: 0, | 
|                     top: 0 | 
|                 }, | 
|                 // 设置字母指示器的高度,后面为了让指示器跟随字母,并将尖角部分指向字母的中部,需要依赖此值 | 
|                 indicatorHeight: 50, | 
|                 // 字母放大指示器的top值,为了让其指向当前激活的字母 | 
|                 // indicatorTop: 0 | 
|                 // 当前是否正在被触摸状态 | 
|                 touching: false, | 
|                 // 滚动条顶部top值 | 
|                 scrollTop: 0, | 
|                 // scroll-view的高度 | 
|                 scrollViewHeight: 0, | 
|                 // 系统信息 | 
|                 sys: uni.$u.sys(), | 
|                 scrolling: false, | 
|                 scrollIntoView: '', | 
|             } | 
|         }, | 
|         computed: { | 
|             // 如果有传入外部的indexList锚点数组则使用,否则使用内部生成A-Z字母 | 
|             uIndexList() { | 
|                 return this.indexList.length ? this.indexList : indexList() | 
|             }, | 
|             // 字母放大指示器的top值,为了让其指向当前激活的字母 | 
|             indicatorTop() { | 
|                 const { | 
|                     top, | 
|                     itemHeight | 
|                 } = this.letterInfo | 
|                 return Math.floor(top + itemHeight * this.activeIndex + itemHeight / 2 - this.indicatorHeight / 2) | 
|             } | 
|         }, | 
|         watch: { | 
|             // 监听字母索引的变化,重新设置尺寸 | 
|             uIndexList: { | 
|                 immediate: true, | 
|                 handler() { | 
|                     uni.$u.sleep().then(() => { | 
|                         this.setIndexListLetterInfo() | 
|                     }) | 
|                 } | 
|             } | 
|         }, | 
|         created() { | 
|             this.children = [] | 
|             this.anchors = [] | 
|             this.init() | 
|         }, | 
|         mounted() { | 
|             this.setIndexListLetterInfo() | 
|         }, | 
|         methods: { | 
|             init() { | 
|                 // 设置列表的高度为整个屏幕的高度 | 
|                 //减去this.customNavHeight,并将this.scrollViewHeight设置为maxHeight | 
|                 //解决当u-index-list组件放在tabbar页面时,scroll-view内容较少时,还能滚动 | 
|                 this.scrollViewHeight = this.sys.windowHeight - this.customNavHeight | 
|             }, | 
|             // 索引列表被触摸 | 
|             touchStart(e) { | 
|                 // 获取触摸点信息 | 
|                 const touchStart = e.changedTouches[0] | 
|                 if (!touchStart) return | 
|                 this.touching = true | 
|                 const { | 
|                     pageY | 
|                 } = touchStart | 
|                 // 根据当前触摸点的坐标,获取当前触摸的为第几个字母 | 
|                 const currentIndex = this.getIndexListLetter(pageY) | 
|                 this.setValueForTouch(currentIndex) | 
|             }, | 
|             // 索引字母列表被触摸滑动中 | 
|             touchMove(e) { | 
|                 // 获取触摸点信息 | 
|                 let touchMove = e.changedTouches[0] | 
|                 if (!touchMove) return; | 
|   | 
|                 // 滑动结束后迅速开始第二次滑动时候 touching 为 false 造成不显示 indicator 问题 | 
|                 if (!this.touching) { | 
|                     this.touching = true | 
|                 } | 
|                 const { | 
|                     pageY | 
|                 } = touchMove | 
|                 const currentIndex = this.getIndexListLetter(pageY) | 
|                 this.setValueForTouch(currentIndex) | 
|             }, | 
|             // 触摸结束 | 
|             touchEnd(e) { | 
|                 // 延时一定时间后再隐藏指示器,为了让用户看的更直观,同时也是为了消除快速切换u-transition的show带来的影响 | 
|                 uni.$u.sleep(300).then(() => { | 
|                     this.touching = false | 
|                 }) | 
|             }, | 
|             // 获取索引列表的尺寸以及单个字符的尺寸信息 | 
|             getIndexListLetterRect() { | 
|                 return new Promise(resolve => { | 
|                     // 延时一定时间,以获取dom尺寸 | 
|                     // #ifndef APP-NVUE | 
|                     this.$uGetRect('.u-index-list__letter').then(size => { | 
|                         resolve(size) | 
|                     }) | 
|                     // #endif | 
|   | 
|                     // #ifdef APP-NVUE | 
|                     const ref = this.$refs['u-index-list__letter'] | 
|                     dom.getComponentRect(ref, res => { | 
|                         resolve(res.size) | 
|                     }) | 
|                     // #endif | 
|                 }) | 
|             }, | 
|             // 设置indexList索引的尺寸信息 | 
|             setIndexListLetterInfo() { | 
|                 this.getIndexListLetterRect().then(size => { | 
|                     const { | 
|                         height | 
|                     } = size | 
|                     const sys = uni.$u.sys() | 
|                     const windowHeight = sys.windowHeight | 
|                     let customNavHeight = 0 | 
|                     // 消除各端导航栏非原生和原生导致的差异,让索引列表字母对屏幕垂直居中 | 
|                     if (this.customNavHeight == 0) { | 
|                         // #ifdef H5 | 
|                         customNavHeight = sys.windowTop | 
|                         // #endif | 
|                         // #ifndef H5 | 
|                         // 在非H5中,为原生导航栏,其高度不算在windowHeight内,这里设置为负值,后面相加时变成减去其高度的一半 | 
|                         customNavHeight = -(sys.statusBarHeight + 44) | 
|                         // #endif | 
|                     } else { | 
|                         customNavHeight = uni.$u.getPx(this.customNavHeight) | 
|                     } | 
|                     this.letterInfo = { | 
|                         height, | 
|                         // 为了让字母列表对屏幕绝对居中,让其对导航栏进行修正,也即往上偏移导航栏的一半高度 | 
|                         top: (windowHeight - height) / 2 + customNavHeight / 2, | 
|                         itemHeight: Math.floor(height / this.uIndexList.length) | 
|                     } | 
|                 }) | 
|             }, | 
|             // 获取当前被触摸的索引字母 | 
|             getIndexListLetter(pageY) { | 
|                 const { | 
|                     top, | 
|                     height, | 
|                     itemHeight | 
|                 } = this.letterInfo | 
|                 // 对H5的pageY进行修正,这是由于uni-app自作多情在H5中将触摸点的坐标跟H5的导航栏结合导致的问题 | 
|                 // #ifdef H5 | 
|                 pageY += uni.$u.sys().windowTop | 
|                 // #endif | 
|                 // 对第一和最后一个字母做边界处理,因为用户可能在字母列表上触摸到两端的尽头后依然继续滑动 | 
|                 if (pageY < top) { | 
|                     return 0 | 
|                 } else if (pageY >= top + height) { | 
|                     // 如果超出了,取最后一个字母 | 
|                     return this.uIndexList.length - 1 | 
|                 } else { | 
|                     // 将触摸点的Y轴偏移值,减去索引字母的top值,除以每个字母的高度,即可得到当前触摸点落在哪个字母上 | 
|                     return Math.floor((pageY - top) / itemHeight); | 
|                 } | 
|             }, | 
|             // 设置各项由触摸而导致变化的值 | 
|             setValueForTouch(currentIndex) { | 
|                 // 如果偏移量太小,前后得出的会是同一个索引字母,为了防抖,进行返回 | 
|                 if (currentIndex === this.activeIndex) return | 
|                 this.activeIndex = currentIndex | 
|                 // #ifndef APP-NVUE || MP-WEIXIN | 
|                 // 在非nvue中,由于anchor和item都在u-index-item中,所以需要对index-item进行偏移 | 
|                 this.scrollIntoView = `u-index-item-${this.uIndexList[currentIndex].charCodeAt(0)}` | 
|                 // #endif | 
|                 // #ifdef MP-WEIXIN | 
|                 // 微信小程序下,scroll-view的scroll-into-view属性无法对slot中的内容的id生效,只能通过设置scrollTop的形式去移动滚动条 | 
|                 this.scrollTop = this.children[currentIndex].top | 
|                 // #endif | 
|                 // #ifdef APP-NVUE | 
|                 // 在nvue中,由于cell和header为同级元素,所以实际是需要对header(anchor)进行偏移 | 
|                 const anchor = `u-index-anchor-${this.uIndexList[currentIndex]}` | 
|                 dom.scrollToElement(this.anchors[currentIndex].$refs[anchor], { | 
|                     offset: 0, | 
|                     animated: false | 
|                 }) | 
|                 // #endif | 
|             }, | 
|             getHeaderRect() { | 
|                 // 获取header slot的高度,因为list组件中获取元素的尺寸是没有top值的 | 
|                 return new Promise(resolve => { | 
|                     dom.getComponentRect(this.$refs.header, res => { | 
|                         resolve(res.size) | 
|                     }) | 
|                 }) | 
|             }, | 
|             // scroll-view的滚动事件 | 
|             async scrollHandler(e) { | 
|                 if (this.touching || this.scrolling) return | 
|                 // 每过一定时间取样一次,减少资源损耗以及可能带来的卡顿 | 
|                 this.scrolling = true | 
|                 uni.$u.sleep(10).then(() => { | 
|                     this.scrolling = false | 
|                 }) | 
|                 let scrollTop = 0 | 
|                 const len = this.children.length | 
|                 let children = this.children | 
|                 const anchors = this.anchors | 
|                 // #ifdef APP-NVUE | 
|                 // nvue下获取的滚动条偏移为负数,需要转为正数 | 
|                 scrollTop = Math.abs(e.contentOffset.y) | 
|                 // 获取header slot的尺寸信息 | 
|                 const header = await this.getHeaderRect() | 
|                 // item的top值,在nvue下,模拟出的anchor的top,类似非nvue下的index-item的top | 
|                 let top = header.height | 
|                 // 由于list组件无法获取cell的top值,这里通过header slot和各个item之间的height,模拟出类似非nvue下的位置信息 | 
|                 children = this.children.map((item, index) => { | 
|                     const child = { | 
|                         height: item.height, | 
|                         top | 
|                     } | 
|                     // 进行累加,给下一个item提供计算依据 | 
|                     top += item.height + anchors[index].height | 
|                     return child | 
|                 }) | 
|                 // #endif | 
|                 // #ifndef APP-NVUE | 
|                 // 非nvue通过detail获取滚动条位移 | 
|                 scrollTop = e.detail.scrollTop | 
|                 // #endif | 
|                 for (let i = 0; i < len; i++) { | 
|                     const item = children[i], | 
|                         nextItem = children[i + 1] | 
|                     // 如果滚动条高度小于第一个item的top值,此时无需设置任意字母为高亮 | 
|                     if (scrollTop <= children[0].top || scrollTop >= children[len - 1].top + children[len - | 
|                             1].height) { | 
|                         this.activeIndex = -1 | 
|                         break | 
|                     } else if (!nextItem) {  | 
|                         // 当不存在下一个item时,意味着历遍到了最后一个 | 
|                         this.activeIndex = len - 1 | 
|                         break | 
|                     } else if (scrollTop > item.top && scrollTop < nextItem.top) { | 
|                         this.activeIndex = i | 
|                         break | 
|                     } | 
|                 } | 
|             }, | 
|         }, | 
|     } | 
| </script> | 
|   | 
| <style lang="scss" scoped> | 
|     @import "../../libs/css/components.scss"; | 
|   | 
|     .u-index-list { | 
|   | 
|         &__letter { | 
|             position: fixed; | 
|             right: 0; | 
|             text-align: center; | 
|             z-index: 3; | 
|             padding: 0 6px; | 
|   | 
|             &__item { | 
|                 width: 16px; | 
|                 height: 16px; | 
|                 border-radius: 100px; | 
|                 margin: 1px 0; | 
|                 @include flex; | 
|                 align-items: center; | 
|                 justify-content: center; | 
|   | 
|                 &--active { | 
|                     background-color: $u-primary; | 
|                 } | 
|   | 
|                 &__index { | 
|                     font-size: 12px; | 
|                     text-align: center; | 
|                     line-height: 12px; | 
|                 } | 
|             } | 
|         } | 
|   | 
|         &__indicator { | 
|             width: 50px; | 
|             height: 50px; | 
|             border-radius: 100px 100px 0 100px; | 
|             text-align: center; | 
|             color: #ffffff; | 
|             background-color: #c9c9c9; | 
|             transform: rotate(-45deg); | 
|             @include flex; | 
|             justify-content: center; | 
|             align-items: center; | 
|   | 
|             &__text { | 
|                 font-size: 28px; | 
|                 line-height: 28px; | 
|                 font-weight: bold; | 
|                 color: #fff; | 
|                 transform: rotate(45deg); | 
|                 text-align: center; | 
|             } | 
|         } | 
|     } | 
| </style> |