swift - 确定用户保存文档后何时关闭共享表

Question

我正在向用户展示一个共享表，这显然允许他们做很多事情，但就我而言，他们正在将 gpx 文件保存到他们选择的位置。

我想在文档成功保存后显示 UIView，所以我的方法是在操作系统关闭共享表后显示 UIView。但是，我遇到的问题是，如果用户手动关闭共享表选项而不保存文件，则调用委托方法，并且我只希望在用户从共享表中选择一个选项时调用委托方法。

我的代码：

func shareAction() {
    if let dir = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first {
        let fileURL = dir.appendingPathComponent("\(gpxNameTextField.text!).gpx")
        URLSession.shared.dataTask(with: fileURL) { data, response, error in
            guard let data = data, error == nil else { return }
            let tmpURL = FileManager.default.temporaryDirectory
                .appendingPathComponent(response?.suggestedFilename ?? "\(self.gpxNameTextField.text!)")
            do {
                try data.write(to: tmpURL)
                DispatchQueue.main.async {
                    self.share(url: tmpURL)
                    self.deleteDraftGPXFile()
                }
            }
            catch {
                self.presentAlertView(title: "Error Saving File", message: "There was an error saving the GPX file to disk./nError: \(error.localizedDescription)")
                print(error)
            }
        }.resume()
    }
}

func share(url: URL) {
    documentInteractionController.url = url
    documentInteractionController.uti = url.typeIdentifier ?? "public.data, public.content"
    documentInteractionController.name = url.localizedName ?? url.lastPathComponent
    documentInteractionController.presentOptionsMenu(from: view.frame, in: view, animated: true)
    documentInteractionController.delegate = self
}

Answer 1

func shareAction(_ callback: @escaping (Bool) -> () ) {
    if let dir = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first {
        let fileURL = dir.appendingPathComponent("\(gpxNameTextField.text!).gpx")
        URLSession.shared.dataTask(with: fileURL) { data, response, error in
            guard let data = data, error == nil else { return }
            let tmpURL = FileManager.default.temporaryDirectory
                .appendingPathComponent(response?.suggestedFilename ?? "\(self.gpxNameTextField.text!)")
            do {
                try data.write(to: tmpURL)
                DispatchQueue.main.async {
                    self.share(url: tmpURL)
                    self.deleteDraftGPXFile()
                    callback(true)
                }
            }
            catch {
                self.presentAlertView(title: "Error Saving File", message: "There was an error saving the GPX file to disk./nError: \(error.localizedDescription)")
                print(error)
                callback(false)
            }
        }.resume()
    }
}

并使用这种方法

sharedAction() { res in
if res {
// File was saved
}