uniapp前置摄像头拍照功能怎么实现？

<template>
  <view>
        <camera device-position="back" flash="off" @error="error" style="width: 100%; height: 300px;"></camera>
        <button type="primary" @click="takePhoto">拍照</button>
        <view>预览</view>
        <image mode="widthFix" :src="src"></image>
    </view>
</template>

export default {
    data() {
        return {
            src:""
        }
    },
    methods: {
         takePhoto() {
            const ctx = uni.createCameraContext();
            ctx.takePhoto({
                quality: 'high',
                success: (res) => {
                    this.src = res.tempImagePath
                }
            });
        },
        error(e) {
            console.log(e.detail);
        }
    }
}