uniapp制作的app使用saveVideoToPhotosAlbum保存视频到相册失败

这个api需要权限，如果拒绝会出现 saveVideoToPhotosAlbum fail

<template>  
    <view>  
        <text>hello</text>  
        <button @tap="test">click me</button>  
        <video :src="src"></video>  
    </view>  
</template>  

<script>  
    export default {  
        data() {  
            return {  
                src: ''  
            }  
        },  
        methods: {  
            test: function () {  
                var self = this;  
                uni.chooseVideo({  
                    sourceType: ['camera'],  
                    success: function (res) {  
                        self.src = res.tempFilePath;  

                        uni.saveVideoToPhotosAlbum({  
                            filePath: res.tempFilePath,  
                            success: function () {  
                                console.log('save success');  
                            },  
                            fail(err) {  
                                console.log(err);  
                            }  
                        });  
                    }  
                });  
            }  
        }  
    }  
</script>  
<style lang="scss">  

</style>