微信小程序实现下拉刷新动画

var animation = wx.createAnimation({})
var i = 1;
Page({
 data: {
 donghua: true,
 left1: Math.floor(Math.random() * 250 + 1),
 left2: Math.floor(Math.random() * 250 + 1),
 left3: Math.floor(Math.random() * 250 + 1),
 left4: Math.floor(Math.random() * 250 + 1),
 left5: Math.floor(Math.random() * 250 + 1),
 left6: Math.floor(Math.random() * 250 + 1),
 left7: Math.floor(Math.random() * 250 + 1),
 left8: Math.floor(Math.random() * 250 + 1),
 },

 //动画
 donghua: function () {
 var that = this;
 setTimeout(function () {
 animation.translateY(800).step({
 duration: 1600,
 timingFunction: 'ease'
 })
 that.setData({
 ["animationData" + i]: animation.export()
 })
 i++;
 }.bind(that), 200)
 if (i < 9) {
 setTimeout(function () {
 that.donghua()
 }.bind(that), 200)
 } else {
 i = 0;
 animation.translateY(-800).step({
 duration: 10,

 })
 setTimeout(function () {
 for (var y = 0; y < 9; y++) {
 that.setData({
 ["animationData" + y]: animation.export()
 })
 that.setData({
 ["animationData" + y + '.actions[0].animates[0].args[0]']: 0
 })
 }
 }.bind(that), 1500)

 }
 },
 onPullDownRefresh: function () {

 wx.showNavigationBarLoading();


 this.donghua();



 wx.stopPullDownRefresh();
 },

})

<!-- 动画 -->
<block wx:if="{{donghua}}">
 <view class='donghua'>
 <image bindtap='hua' style='left:{{left1}}px' animation="{{animationData1}}" src='../../images/1.png'></image>
 <image bindtap='hua' style='left:{{left2}}px' animation="{{animationData2}}" src='../../images/2.png'></image>
 <image bindtap='hua' style='left:{{left3}}px' animation="{{animationData3}}" src='../../images/3.png'></image>
 <image bindtap='hua' style='left:{{left4}}px' animation="{{animationData4}}" src='../../images/1.png'></image>
 <image bindtap='hua' style='left:{{left5}}px' animation="{{animationData5}}" src='../../images/2.png'></image>
 <image bindtap='hua' style='left:{{left6}}px' animation="{{animationData6}}" src='../../images/3.png'></image>
 <image bindtap='hua' style='left:{{left7}}px' animation="{{animationData7}}" src='../../images/1.png'></image>
 <image bindtap='hua' style='left:{{left8}}px' animation="{{animationData8}}" src='../../images/2.png'></image>
 </view>
</block>

image{
 margin-top: -150rpx;
 width: 40rpx;
 height: 40rpx;
 margin-left: 5%;
 position: absolute;
 
}