在微信小程序中如何实现图片预览功能

<view>
 <button bindtap="previewImage" type="primary">图片上传预览</button>
 <view class="tui-content"> 
  <image class="tui-preview-img" wx:for="{{previewImageArr}}" bindtap="changePreview" src="{{item}}" src="{{item}}"></image>
 </view>
</view>

page{background-color: #efeff4;}
.tui-preview-img{
 width: 200rpx;
 height: 120rpx;
}

Page({
 data: {
  previewImageArr:[]
 },
 previewImage(e){
  var self = this;
  wx.chooseImage({
   count:8,
   success(res) {
    var tempFilePaths = res.tempFilePaths;
    self.setData({ previewImageArr: tempFilePaths});
   }
  })
 },
 changePreview(e){
  var self = this;
  wx.previewImage({
   current: e.currentTarget.dataset.src,
   urls: self.data.previewImageArr
  })
 }
})