$ npm i v-qrcode --save

<template>
    <div>
        <qrcode :cls="qrCls" :value="qrText"></qrcode>
    </div>
</template>

<script>
import Qrcode from 'v-qrcode'

export default {
    data () {
        return {
            qrCls: 'qrcode',

            qrText: 'hello world'
        }
    },

    components: {
        Qrcode
    }
}
</script>

<script src="path/to/vue.js"></script>
<script src="path/to/v-qrcode.min.js"></script>
<script>
    var qrcode = VQrcode.qrcode;
</script>