<div class="handle">
            <button class="btn" open-type="{{saveset}}" @tap="bindSave">
                <img src="@/images/icon_download_white.png" alt="" mode="widthFix" />保存二维码
            </button>
            <button class="btn" open-type="share"><img src="@/images/icon_share_white.png" alt="" mode="widthFix" />分享给好友</button>
</div>

// 保存图片
            bindSave(e) {
                console.log(e)
                let that = this;
                wx.getSetting({//检查小程序的授权状态
success(res) {
    console.log(res)//授权后的回调
    if (!res.authSetting[‘scope.writePhotosAlbum‘]) {
        wx.authorize({//调用 wx.authorize 弹出对话窗提醒用户是否要授权小程序得到他的授权
            scope: ‘scope.writePhotosAlbum‘,
            success(t) {//这里是用户同意授权后的回调
                console.log("这里是用户同意授权后的回调", t)
                that.saveset = "";
                that.getImage();
            },
            fail(err) {//这里是用户拒绝授权后的回调
                console.log("这里是用户拒绝授权后的回调", err);
                that.saveset = "openSetting";
                if (err.errMsg == "authorize:fail:auth deny") {//如果用户拒绝打开授权接口，通过button按钮的open-type="openSetting"属性来调起授权窗口
console.log("打开设置窗口");
if (that.data.saveset == "openSetting"){
    console.log("第二次进来",that.data.opensett);
    wx.openSetting({
        success(settingdata) {
            console.log(settingdata)
            if (settingdata.authSetting["scope.writePhotosAlbum"]) {
                console.log("获取权限成功，再次点击图片保存到相册")
                that.setData({
saveset: ""
                });
            } else {
                console.log("获取权限失败")
            }
        }
    });
}
                }
            }
        })
    } else {//用户已经授权过了
        console.log("用户已经授权过了")
        that.saveset = "";
        that.getImage();
    }
}
                })
            },
            getImage(){
                wx.downloadFile({
url: ‘https://xcx.rejoint.com.cn/uploads/avatar/201908/29/BwCOi6fRPzsD6ZX5LstG7FPdwqHC9u8UOH90UCew.png‘, //测试图片
success: function (res) {
    console.log(res);
    //图片保存到本地
    wx.saveImageToPhotosAlbum({
        filePath: res.tempFilePath,
        success: function (data) {
            console.log("保存到相册", data);
            wx.showToast({
              title: ‘保存成功‘,
              icon: "none"
            })
          },
        fail: function (err) {
            console.log(err)
        }
    })
}
                })
            }