基于vue实现探探滑动组件功能

前言

嗨，说起探探想必各位程序汪都不陌生(毕竟妹子很多)，能在上面丝滑的翻牌子，探探的的堆叠滑动组件起到了关键的作用，下面就来看看如何用vue写一个探探的堆叠组件 ?

一. 功能分析

简单使用下探探会发现，堆叠滑动的功能很简单，用一张图概括就是:

简单归纳下里面包含的基本功能点:

• 图片的堆叠
• 图片第一张的滑动
• 条件成功后的滑出，条件失败后的回弹
• 滑出后下一张图片堆叠到顶部
  

体验优化

根据触摸点的不同，滑动时首图有不同角度偏移

偏移面积判定是否成功滑出

二. 具体实现

有了归纳好的功能点，我们实现组件的思路会更清晰

1. 堆叠效果

堆叠图片效果在网上有大量的实例，实现的方法大同小异，主要通过在父层设定perspective及perspective-origin，来实现子层的透视，子层设定好translate3d Z轴数值即可模拟出堆叠效果，具体代码如下

// 图片堆叠dom
 <!--opacity: 0 隐藏我们不想看到的stack-item层级-->
 <!--z-index: -1 调整stack-item层级"-->
<ul class="stack">
 <li class="stack-item" style="transform: translate3d(0px, 0px, 0px);opacity: 1;z-index: 10;"><img src="1.png" alt="01"></li>
 <li class="stack-item" style="transform: translate3d(0px, 0px, -60px);opacity: 1;z-index: 1"><img src="2.png" alt="02"></li>
 <li class="stack-item" style="transform: translate3d(0px, 0px, -120px);opacity: 1;z-index: 1"><img src="3.png" alt="03"></li>
 <li class="stack-item" style="transform: translate3d(0px, 0px, -180px);opacity: 0;z-index: -1"><img src="4.png" alt="04"></li>
 <li class="stack-item" style="transform: translate3d(0px, 0px, -180px);opacity: 0;z-index: -1"><img src="5.png" alt="05"></li>
</ul>
<style>
.stack {
  width: 100%;
  height: 100%;
  position: relative;
  perspective: 1000px; //子元素视距
  perspective-origin: 50% 150%; //子元素透视位置
  -webkit-perspective: 1000px;
  -webkit-perspective-origin: 50% 150%;
  margin: 0;
  padding: 0;
 }
 .stack-item{
  background: #fff;
  height: 100%;
  width: 100%;
  border-radius: 4px;
  text-align: center;
  overflow: hidden;
 }
 .stack-item img {
  width: 100%;
  display: block;
  pointer-events: none;
 }
</style>

上面只是一组静态代码，我们希望得到的是vue组件，所以需要先建立一个组件模板stack.vue，在模板中我们可以使用v-for，遍历出stack节点，使用:style 来修改各个item的style，代码如下

<template>
  <ul class="stack">
   <li class="stack-item" v-for="(item, index) in pages" :style="[transform(index)]">
    <img :src="item.src">
   </li>
  </ul>
</template>
<script>
export default {
 props: {
  // pages数据包含基础的图片数据
  pages: {
   type: Array,
   default: []
  }
 },
 data () {
  return {
   // basicdata数据包含组件基本数据
   basicdata: {
    currentPage: 0 // 默认首图的序列
   },
   // temporaryData数据包含组件临时数据
   temporaryData: {
    opacity: 1, // 记录opacity
    zIndex: 10, // 记录zIndex
    visible: 3 // 记录默认显示堆叠数visible
   }
  }
 },
 methods: {
  // 遍历样式
  transform (index) {
   if (index >= this.basicdata.currentPage) {
    let style = {}
    let visible = this.temporaryData.visible
    let perIndex = index - this.basicdata.currentPage
    // visible可见数量前滑块的样式
    if (index <= this.basicdata.currentPage + visible - 1) {
     style['opacity'] = '1'
     style['transform'] = 'translate3D(0,0,' + -1 * perIndex * 60 + 'px' + ')'
     style['zIndex'] = visible - index + this.basicdata.currentPage
     style['transitionTimingFunction'] = 'ease'
     style['transitionDuration'] = 300 + 'ms'
    } else {
     style['zIndex'] = '-1'
     style['transform'] = 'translate3D(0,0,' + -1 * visible * 60 + 'px' + ')'
    }
    return style
   }
  }
 }
}
</script>

关键点

style可以绑定对象的同时，也可以绑定数组和函数，这在遍历的时候很有用

最基本的dom结构已经构建完毕，下一步是让首张图片“动”起来

2. 图片滑动

图片滑动效果，在很多场景中都有出现，其原理无非是监听touchs事件，得到位移，再通过translate3D改变目标位移，因此我们要实现的步骤如下

• 对stack进行touchs事件的绑定
• 监听并储存手势位置变化的数值
• 改变首图css属性中translate3D的x，y值
  

具体实现

在vue框架中，不建议直接操作节点，而是通过指令v-on对元素进行绑定，因此我们将绑定都写在v-for遍历里，通过index进行判断其是否是首图，再使用:style修改首页的样式，具体代码如下:

<template>
  <ul class="stack">
   <li class="stack-item" v-for="(item, index) in pages"
   :style="[transformIndex(index),transform(index)]"
   @touchstart.stop.capture="touchstart"
   @touchmove.stop.capture="touchmove"
   @touchend.stop.capture="touchend"
   @mousedown.stop.capture="touchstart"
   @mouseup.stop.capture="touchend"
   @mousemove.stop.capture="touchmove">
    <img :src="item.src">
   </li>
  </ul>
</template>
<script>
export default {
 props: {
  // pages数据包含基础的图片数据
  pages: {
   type: Array,
   default: []
  }
 },
 data () {
  return {
   // basicdata数据包含组件基本数据
   basicdata: {
    start: {}, // 记录起始位置
    end: {}, // 记录终点位置
    currentPage: 0 // 默认首图的序列
   },
   // temporaryData数据包含组件临时数据
   temporaryData: {
    poswidth: '', // 记录位移
    posheight: '', // 记录位移
    tracking: false // 是否在滑动，防止多次操作，影响体验
   }
  }
 },
 methods: {
  touchstart (e) {
   if (this.temporaryData.tracking) {
    return
   }
   // 是否为touch
   if (e.type === 'touchstart') {
    if (e.touches.length > 1) {
     this.temporaryData.tracking = false
     return
    } else {
     // 记录起始位置
     this.basicdata.start.t = new Date().getTime()
     this.basicdata.start.x = e.targetTouches[0].clientX
     this.basicdata.start.y = e.targetTouches[0].clientY
     this.basicdata.end.x = e.targetTouches[0].clientX
     this.basicdata.end.y = e.targetTouches[0].clientY
    }
   // pc操作
   } else {
    this.basicdata.start.t = new Date().getTime()
    this.basicdata.start.x = e.clientX
    this.basicdata.start.y = e.clientY
    this.basicdata.end.x = e.clientX
    this.basicdata.end.y = e.clientY
   }
   this.temporaryData.tracking = true
  },
  touchmove (e) {
   // 记录滑动位置
   if (this.temporaryData.tracking && !this.temporaryData.animation) {
    if (e.type === 'touchmove') {
     this.basicdata.end.x = e.targetTouches[0].clientX
     this.basicdata.end.y = e.targetTouches[0].clientY
    } else {
     this.basicdata.end.x = e.clientX
     this.basicdata.end.y = e.clientY
    }
    // 计算滑动值
    this.temporaryData.poswidth = this.basicdata.end.x - this.basicdata.start.x
    this.temporaryData.posheight = this.basicdata.end.y - this.basicdata.start.y
   }
  },
  touchend (e) {
   this.temporaryData.tracking = false
   // 滑动结束，触发判断
  },
  // 非首页样式切换
  transform (index) {
   if (index > this.basicdata.currentPage) {
    let style = {}
    let visible = 3
    let perIndex = index - this.basicdata.currentPage
    // visible可见数量前滑块的样式
    if (index <= this.basicdata.currentPage + visible - 1) {
     style['opacity'] = '1'
     style['transform'] = 'translate3D(0,0,' + -1 * perIndex * 60 + 'px' + ')'
     style['zIndex'] = visible - index + this.basicdata.currentPage
     style['transitionTimingFunction'] = 'ease'
     style['transitionDuration'] = 300 + 'ms'
    } else {
     style['zIndex'] = '-1'
     style['transform'] = 'translate3D(0,0,' + -1 * visible * 60 + 'px' + ')'
    }
    return style
   }
  },
  // 首页样式切换
  transformIndex (index) {
   // 处理3D效果
   if (index === this.basicdata.currentPage) {
    let style = {}
    style['transform'] = 'translate3D(' + this.temporaryData.poswidth + 'px' + ',' + this.temporaryData.posheight + 'px' + ',0px)'
    style['opacity'] = 1
    style['zIndex'] = 10
    return style
   }
  }
 }
}
</script>

3. 条件成功后的滑出，条件失败后的回弹

条件的触发判断是在touchend/mouseup后进行，在这里我们先用简单的条件进行判定，同时给予首图弹出及回弹的效果，代码如下

<template>
  <ul class="stack">
   <li class="stack-item" v-for="(item, index) in pages"
   :style="[transformIndex(index),transform(index)]"
   @touchmove.stop.capture="touchmove"
   @touchstart.stop.capture="touchstart"
   @touchend.stop.capture="touchend"
   @mousedown.stop.capture="touchstart"
   @mouseup.stop.capture="touchend"
   @mousemove.stop.capture="touchmove">
    <img :src="item.src">
   </li>
  </ul>
</template>
<script>
export default {
 props: {
   // pages数据包含基础的图片数据
  pages: {
   type: Array,
   default: []
  }
 },
 data () {
  return {
   // basicdata数据包含组件基本数据
   basicdata: {
    start: {}, // 记录起始位置
    end: {}, // 记录终点位置
    currentPage: 0 // 默认首图的序列
   },
   // temporaryData数据包含组件临时数据
   temporaryData: {
    poswidth: '', // 记录位移
    posheight: '', // 记录位移
    tracking: false, // 是否在滑动，防止多次操作，影响体验
    animation: false, // 首图是否启用动画效果，默认为否
    opacity: 1 // 记录首图透明度
   }
  }
 },
 methods: {
  touchstart (e) {
   if (this.temporaryData.tracking) {
    return
   }
   // 是否为touch
   if (e.type === 'touchstart') {
    if (e.touches.length > 1) {
     this.temporaryData.tracking = false
     return
    } else {
     // 记录起始位置
     this.basicdata.start.t = new Date().getTime()
     this.basicdata.start.x = e.targetTouches[0].clientX
     this.basicdata.start.y = e.targetTouches[0].clientY
     this.basicdata.end.x = e.targetTouches[0].clientX
     this.basicdata.end.y = e.targetTouches[0].clientY
    }
   // pc操作
   } else {
    this.basicdata.start.t = new Date().getTime()
    this.basicdata.start.x = e.clientX
    this.basicdata.start.y = e.clientY
    this.basicdata.end.x = e.clientX
    this.basicdata.end.y = e.clientY
   }
   this.temporaryData.tracking = true
   this.temporaryData.animation = false
  },
  touchmove (e) {
   // 记录滑动位置
   if (this.temporaryData.tracking && !this.temporaryData.animation) {
    if (e.type === 'touchmove') {
     this.basicdata.end.x = e.targetTouches[0].clientX
     this.basicdata.end.y = e.targetTouches[0].clientY
    } else {
     this.basicdata.end.x = e.clientX
     this.basicdata.end.y = e.clientY
    }
    // 计算滑动值
    this.temporaryData.poswidth = this.basicdata.end.x - this.basicdata.start.x
    this.temporaryData.posheight = this.basicdata.end.y - this.basicdata.start.y
   }
  },
  touchend (e) {
   this.temporaryData.tracking = false
   this.temporaryData.animation = true
   // 滑动结束，触发判断
   // 简单判断滑动宽度超出100像素时触发滑出
   if (Math.abs(this.temporaryData.poswidth) >= 100) {
    // 最终位移简单设定为x轴200像素的偏移
    let ratio = Math.abs(this.temporaryData.posheight / this.temporaryData.poswidth)
    this.temporaryData.poswidth = this.temporaryData.poswidth >= 0 ? this.temporaryData.poswidth + 200 : this.temporaryData.poswidth - 200
    this.temporaryData.posheight = this.temporaryData.posheight >= 0 ? Math.abs(this.temporaryData.poswidth * ratio) : -Math.abs(this.temporaryData.poswidth * ratio)
    this.temporaryData.opacity = 0
   // 不满足条件则滑入
   } else {
    this.temporaryData.poswidth = 0
    this.temporaryData.posheight = 0
   }
  },
  // 非首页样式切换
  transform (index) {
   if (index > this.basicdata.currentPage) {
    let style = {}
    let visible = 3
    let perIndex = index - this.basicdata.currentPage
    // visible可见数量前滑块的样式
    if (index <= this.basicdata.currentPage + visible - 1) {
     style['opacity'] = '1'
     style['transform'] = 'translate3D(0,0,' + -1 * perIndex * 60 + 'px' + ')'
     style['zIndex'] = visible - index + this.basicdata.currentPage
     style['transitionTimingFunction'] = 'ease'
     style['transitionDuration'] = 300 + 'ms'
    } else {
     style['zIndex'] = '-1'
     style['transform'] = 'translate3D(0,0,' + -1 * visible * 60 + 'px' + ')'
    }
    return style
   }
  },
  // 首页样式切换
  transformIndex (index) {
   // 处理3D效果
   if (index === this.basicdata.currentPage) {
    let style = {}
    style['transform'] = 'translate3D(' + this.temporaryData.poswidth + 'px' + ',' + this.temporaryData.posheight + 'px' + ',0px)'
    style['opacity'] = this.temporaryData.opacity
    style['zIndex'] = 10
    if (this.temporaryData.animation) {
     style['transitionTimingFunction'] = 'ease'
     style['transitionDuration'] = 300 + 'ms'
    }
    return style
   }
  }
 }
}
</script>

4. 滑出后下一张图片堆叠到顶部

重新堆叠是组件最后一个功能，同时也是最重要和复杂的功能。在我们的代码里，stack-item的排序依赖绑定:style的transformIndex和transform函数，函数里判定的条件是currentPage，那是不是改变currentPage，让其+1，即可完成重新堆叠呢？

答案没有那么简单，因为我们滑出是动画效果，会进行300ms的时间，而currentPage变化引起的重排，会立即变化，打断动画的进行。因此我们需要先修改transform函数的排序条件，后改变currentPage。

具体实现

• 修改transform函数排序条件
• 让currentPage+1
• 添加onTransitionEnd事件，在滑出结束后，重新放置stack列表中
  

代码如下：

<template>
  <ul class="stack">
   <li class="stack-item" v-for="(item, index) in pages"
   :style="[transformIndex(index),transform(index)]"
   @touchmove.stop.capture="touchmove"
   @touchstart.stop.capture="touchstart"
   @touchend.stop.capture="touchend"
   @mousedown.stop.capture="touchstart"
   @mouseup.stop.capture="touchend"
   @mousemove.stop.capture="touchmove"
   @webkit-transition-end="onTransitionEnd"
   @transitionend="onTransitionEnd"
   >
    <img :src="item.src">
   </li>
  </ul>
</template>
<script>
export default {
 props: {
  // pages数据包含基础的图片数据
  pages: {
   type: Array,
   default: []
  }
 },
 data () {
  return {
   // basicdata数据包含组件基本数据
   basicdata: {
    start: {}, // 记录起始位置
    end: {}, // 记录终点位置
    currentPage: 0 // 默认首图的序列
   },
   // temporaryData数据包含组件临时数据
   temporaryData: {
    poswidth: '', // 记录位移
    posheight: '', // 记录位移
    lastPosWidth: '', // 记录上次最终位移
    lastPosHeight: '', // 记录上次最终位移
    tracking: false, // 是否在滑动，防止多次操作，影响体验
    animation: false, // 首图是否启用动画效果，默认为否
    opacity: 1, // 记录首图透明度
    swipe: false // onTransition判定条件
   }
  }
 },
 methods: {
  touchstart (e) {
   if (this.temporaryData.tracking) {
    return
   }
   // 是否为touch
   if (e.type === 'touchstart') {
    if (e.touches.length > 1) {
     this.temporaryData.tracking = false
     return
    } else {
     // 记录起始位置
     this.basicdata.start.t = new Date().getTime()
     this.basicdata.start.x = e.targetTouches[0].clientX
     this.basicdata.start.y = e.targetTouches[0].clientY
     this.basicdata.end.x = e.targetTouches[0].clientX
     this.basicdata.end.y = e.targetTouches[0].clientY
    }
   // pc操作
   } else {
    this.basicdata.start.t = new Date().getTime()
    this.basicdata.start.x = e.clientX
    this.basicdata.start.y = e.clientY
    this.basicdata.end.x = e.clientX
    this.basicdata.end.y = e.clientY
   }
   this.temporaryData.tracking = true
   this.temporaryData.animation = false
  },
  touchmove (e) {
   // 记录滑动位置
   if (this.temporaryData.tracking && !this.temporaryData.animation) {
    if (e.type === 'touchmove') {
     this.basicdata.end.x = e.targetTouches[0].clientX
     this.basicdata.end.y = e.targetTouches[0].clientY
    } else {
     this.basicdata.end.x = e.clientX
     this.basicdata.end.y = e.clientY
    }
    // 计算滑动值
    this.temporaryData.poswidth = this.basicdata.end.x - this.basicdata.start.x
    this.temporaryData.posheight = this.basicdata.end.y - this.basicdata.start.y
   }
  },
  touchend (e) {
   this.temporaryData.tracking = false
   this.temporaryData.animation = true
   // 滑动结束，触发判断
   // 简单判断滑动宽度超出100像素时触发滑出
   if (Math.abs(this.temporaryData.poswidth) >= 100) {
    // 最终位移简单设定为x轴200像素的偏移
    let ratio = Math.abs(this.temporaryData.posheight / this.temporaryData.poswidth)
    this.temporaryData.poswidth = this.temporaryData.poswidth >= 0 ? this.temporaryData.poswidth + 200 : this.temporaryData.poswidth - 200
    this.temporaryData.posheight = this.temporaryData.posheight >= 0 ? Math.abs(this.temporaryData.poswidth * ratio) : -Math.abs(this.temporaryData.poswidth * ratio)
    this.temporaryData.opacity = 0
    this.temporaryData.swipe = true
    // 记录最终滑动距离
    this.temporaryData.lastPosWidth = this.temporaryData.poswidth
    this.temporaryData.lastPosHeight = this.temporaryData.posheight
    // currentPage+1 引发排序变化
    this.basicdata.currentPage += 1
    // currentPage切换，整体dom进行变化，把第一层滑动置零
    this.$nextTick(() => {
     this.temporaryData.poswidth = 0
     this.temporaryData.posheight = 0
     this.temporaryData.opacity = 1
    })
   // 不满足条件则滑入
   } else {
    this.temporaryData.poswidth = 0
    this.temporaryData.posheight = 0
    this.temporaryData.swipe = false
   }
  },
  onTransitionEnd (index) {
   // dom发生变化后，正在执行的动画滑动序列已经变为上一层
   if (this.temporaryData.swipe && index === this.basicdata.currentPage - 1) {
    this.temporaryData.animation = true
    this.temporaryData.lastPosWidth = 0
    this.temporaryData.lastPosHeight = 0
    this.temporaryData.swipe = false
   }
  },
  // 非首页样式切换
  transform (index) {
   if (index > this.basicdata.currentPage) {
    let style = {}
    let visible = 3
    let perIndex = index - this.basicdata.currentPage
    // visible可见数量前滑块的样式
    if (index <= this.basicdata.currentPage + visible - 1) {
     style['opacity'] = '1'
     style['transform'] = 'translate3D(0,0,' + -1 * perIndex * 60 + 'px' + ')'
     style['zIndex'] = visible - index + this.basicdata.currentPage
     style['transitionTimingFunction'] = 'ease'
     style['transitionDuration'] = 300 + 'ms'
    } else {
     style['zIndex'] = '-1'
     style['transform'] = 'translate3D(0,0,' + -1 * visible * 60 + 'px' + ')'
    }
    return style
   // 已滑动模块释放后
   } else if (index === this.basicdata.currentPage - 1) {
    let style = {}
    // 继续执行动画
    style['transform'] = 'translate3D(' + this.temporaryData.lastPosWidth + 'px' + ',' + this.temporaryData.lastPosHeight + 'px' + ',0px)'
    style['opacity'] = '0'
    style['zIndex'] = '-1'
    style['transitionTimingFunction'] = 'ease'
    style['transitionDuration'] = 300 + 'ms'
    return style
   }
  },
  // 首页样式切换
  transformIndex (index) {
   // 处理3D效果
   if (index === this.basicdata.currentPage) {
    let style = {}
    style['transform'] = 'translate3D(' + this.temporaryData.poswidth + 'px' + ',' + this.temporaryData.posheight + 'px' + ',0px)'
    style['opacity'] = this.temporaryData.opacity
    style['zIndex'] = 10
    if (this.temporaryData.animation) {
     style['transitionTimingFunction'] = 'ease'
     style['transitionDuration'] = 300 + 'ms'
    }
    return style
   }
  }
 }
}
</script>

ok~ 完成了上面的四步，堆叠组件的基本功能就已经实现，快来看看效果吧

堆叠滑动效果已经出来了，但是探探在体验上，还增加了触碰角度偏移，以及判定滑出面积比例

角度偏移的原理，是在用户每次进行touch时，记录用户触碰位置，计算出最大的偏移角度，在滑动出现位移时，线性增加角度以至最大的偏移角度。

使用在stack中具体要做的是：

touchmove中计算出所需角度和方向

touchend及onTransitionEnd中将角度至零

判定滑出面积比例，主要通过偏移量计算出偏移面积，从而得到面积比例，完成判断

完整的代码和demo可以在github上查看源码，这里就不贴出来了

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持易盾网络。