微信小程序实现保存图片到相册功能

<view bindtap='save'>保存图片到相册</view>

//点击保存图片 save () {  let that = this  //若二维码未加载完毕，加个动画提高用户体验  wx.showToast({   icon: 'loading',   title: '正在保存图片',   duration: 1000  })  //判断用户是否授权"保存到相册"  wx.getSetting({   success (res) {    //没有权限，发起授权    if (!res.authSetting['scope.writePhotosAlbum']) {     wx.authorize({      scope: 'scope.writePhotosAlbum',      success () {//用户允许授权，保存图片到相册       that.savePhoto();      },      fail () {//用户点击拒绝授权，跳转到设置页，引导用户授权       wx.openSetting({        success () {         wx.authorize({          scope: 'scope.writePhotosAlbum',          success() {           that.savePhoto();          }         })        }       })      }     })    } else {//用户已授权，保存到相册     that.savePhoto()    }   }  }) },//保存图片到相册，提示保存成功 savePhoto() {  let that = this  wx.downloadFile({   url: that.data.imgUrl,   success: function (res) {    wx.saveImageToPhotosAlbum({     filePath: res.tempFilePath,     success(res) {      wx.showToast({       title: '保存成功',       icon: "success",       duration: 1000      })     }    })   }  }) }