微信小程序实现banner图轮播（动态获取数据），自动获取图片高度

效果图：

indicator-active-color="#007aff"//修改选中图片圆点的颜色 

js:

[code]const app = getApp()

Page({
data: {
//-----------模拟banner图-----------
imgUrls: [
'http://cigtb.cn/upload/image/1545118381903.jpg',
'http://cigtb.cn/upload/image/1545118566631.jpg'
],
circular: true,
//是否显示画板指示点
indicatorDots: true,
//选中点的颜色
//是否竖直
vertical: false,
//是否自动切换
autoplay: true,
//自动切换的间隔
interval: 3000,
//滑动动画时长毫秒
duration: 1000,
//所有图片的高度
imgheights: [],
//图片宽度
imgwidth: 750,
//默认
current: 0
},
imageLoad: function (e) {//获取图片真实宽度
var imgwidth = e.detail.width,
imgheight = e.detail.height,
//宽高比
ratio = imgwidth / imgheight;
console.log(imgwidth, imgheight)
//计算的高度值
var viewHeight = 750 / ratio;
var imgheight = viewHeight;
var imgheights = this.data.imgheights;
//把每一张图片的对应的高度记录到数组里
imgheights[e.target.dataset.id] = imgheight;
this.setData({
imgheights: imgheights
})
},
bindchange: function (e) {
// console.log(e.detail.current)
this.setData({ current: e.detail.current })
},
}
})

wxml:

[code]<!-------------首页轮播图-----------------  -->
<view class='swiper'>
<swiper indicator-dots="{{indicatorDots}}" vertical="{{vertical}}" autoplay="{{autoplay}}" duration="{{duration}}" interval='{{interval}}'indicator-active-color="#007aff" bindchange="bindchange" circular="{{circular}}" style="height:{{imgheights[current]}}rpx;">
<block wx:for='{{imgUrls}}' wx:key="{{index}}">
<swiper-item>
<image src="{{item}}" data-id='{{index}}' class="slide-image" mode="widthFix" bindload="imageLoad" />
</swiper-item>
</block>
</swiper>
</view>

wxss:

[code].swiper image {
width: 100%;
height: auto;
}

.swiper-image {
height: 100%;
width: 100%;
}

.slide-image {
height: 100%;
width: 100%;
display: block;
}