成功下载但在iOS设备上找不到文件-rn-fetch-blob

Question

我使用rn-fetch-blob从api下载文件。我可以看到它已成功下载，但是如您所知，在iOS平台上，每次访问文件系统时，目录路径都会更改。

但是当我转到设备的文件夹时，没有文件可以看到。如何下载并编写用户可以看到其设备的路径？

getFileName = async (url) => {
    return await url.split('/api/files/others/')[1]
}

download = async () => {

    let permissions = await this.requestCameraPermission()

    if (!permissions && Platform.OS !== 'ios') {
        Platform.OS === 'ios' ? RNToasty.Normal({ title: 'Storage permissions are required!' }) : RNToasty.Error({ title: 'Storage permissions are required!' })
        return
    }
    try {

        this.setState({ showDialog: true })

        let file = this.props.navigation.state.params.article.files[0];
        let fileName = await this.getFileName(file)
        console.log({ fileName, file })
        res = await RNFetchBlob.config({
            fileCache: true,
            path: Platform.OS === 'ios'? RNFetchBlob.fs.dirs.MainBundleDir + "/QCIPA/" + this.props.navigation.state.params.article.title + "/" + fileName : RNFetchBlob.fs.dirs.DownloadDir + "/QCIPA/" + this.props.navigation.state.params.article.title + "/" + fileName
        })
            .fetch('GET', Root + file + '?download=1')
            .progress((received, total) => {
                let downloadProgress = (received) / total
                this.setState({ downloadProgress })
                console.log({ downloadProgress, received, total })
            })


        Platform.OS === 'ios' ? RNToasty.Normal({ title: 'All Files Downloaded...' }) : RNToasty.Success({ title: 'All Files Downloaded...' })
        this.setState({ showDialog: false })

        console.log('The file saved to ', res.path(), { res });
        this.setState({ showDialog: false })
    } catch (error) {
        Platform.OS === 'ios' ? RNToasty.Normal({ title: error.message }) : RNToasty.Error({ title: error.message })
        this.setState({ showDialog: false })
    }



}

static navigationOptions = ({ navigation }) => {
    return {
        header: (props) => <HeaderBackground {...props} />,
        headerStyle: {
            backgroundColor: Colors.transparent,
            paddingTop: Platform.OS === 'ios' ? 0 : getStatusBarHeight(),
            height: Header.HEIGHT + (Platform.OS === 'ios' ? 0 : getStatusBarHeight()),
        },
        title: navigation.state.params.article.title,
        headerTintColor: Colors.white,
        headerTitleStyle: {
            fontWeight: 'bold',
            padding: 5,
            paddingTop: 10
        },
        headerMode: 'float',
        headerLeft: <Icon
            onPress={() => navigation.goBack()}
            name="arrow-back"
            type='MaterialIcons'
            style={{ color: 'white', marginLeft: 10, padding: 5, paddingTop: 10 }}
        />,
    }
}