在Oreo版本8上从未知道过uri

Question

我有一个运行在版本8中的应用程序，该应用程序打开一个本地CSV文件，并且在搜索realpath文件时，像oreo版本8一样的DocumentsContract.isDocumentUri（this，uri）函数找不到该文件，因此它总是产生虚假条件，也许有人经历过类似的情况

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    let url = URL(string: "about:blank")
    let request = URLRequest(url: url!)
    myGraphView.loadRequest(request)
}

我希望本地CSV文件可由应用程序版本8读取

the line ignored by the application, it is assumed that the file path is not appropriate this is the result of debugging the file path located