uniapp调取摄像头扫码和生成二维码

<view @click="scan">扫码验证</view>
scan() { //扫码验证
    var _this = this;
    uni.scanCode({
　　　　　onlyFromCamera: true, //为true只允许相机扫码，不加允许相册扫码
        success: function(res) {
            uni.showToast({
                title: ‘扫码成功‘
            })
        },
        fail: function(err) {
            console.log(‘扫码失败‘, err)
        }
    })
},

<view class="qrcode">
                <canvas style="width: 200upx;height: 200upx;" canvas-id="couponQrcode"></canvas>
</view>

<script>
    const qrCode = require(‘../../libs/weapp-qrcode.js‘)
        methods: {
            //二维码生成工具
            couponQrCode() {
                new qrCode(‘couponQrcode‘, {
                    text: "加入你所需要的参数",
                    width: 100,
                    height: 100,
                    showLoading: true, // 是否显示loading
                    loadingText: ‘二维码生成中‘, // loading文字
                    colorDark: "#333333",
                    colorLight: "#FFFFFF",
                    correctLevel: qrCode.CorrectLevel.H
                })
            },


        }
</script>