如何解决关闭UIDocumentPickerViewController时的报错问题

云上老周

2026-7-29

解决UIDocumentPickerViewController关闭时的报错问题

我正在开发iOS应用，通过UIDocumentPickerViewController允许用户从Files app选择PDF文件并保存到应用文档目录。目前已实现打开选择器和选择文件的功能，但关闭选择器时出现报错：

"[DocumentManager] The view service did terminate with error: Error Domain=_UIViewServiceErrorDomain Code=1 "(null)" UserInfo={Terminated=disconnect method}"

相关UIViewController代码如下：

import UIKit
import CoreData
import PDFKit
import MobileCoreServices
import UniformTypeIdentifiers

class AddDocumentViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate, UIDocumentPickerDelegate {

    @IBAction func chooseFile (_ sender: UIButton) {
        fileTypeSelectionInput = fileTypeSelection.selectedSegmentIndex
        
        var documentPicker: UIDocumentPickerViewController!
        if #available(iOS 14, *) {
            // iOS 14 & later
            let supportedTypes: [UTType] = [UTType.pdf]
            documentPicker = UIDocumentPickerViewController(forOpeningContentTypes: supportedTypes)
        } else {
            // iOS 13 or older code
            let supportedTypes: [String] = [kUTTypeImage as String]
            documentPicker = UIDocumentPickerViewController(documentTypes: supportedTypes, in: .import)
        }
        documentPicker.delegate = self
        documentPicker.allowsMultipleSelection = false
        documentPicker.modalPresentationStyle = .formSheet
        self.present(documentPicker, animated: true) 
    }

    func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
        let fileURL = urls[0]
        var fileName = urls[0].lastPathComponent
        subjectFileName = fileName
        let filePath = getDocumentsDirectory().appendingPathComponent(fileName)
        print(fileName)
        
        guard fileURL.startAccessingSecurityScopedResource() else {
            // Handle denied access
            return
        }
        defer { fileURL.stopAccessingSecurityScopedResource() }

        do {
            guard let document = PDFDocument(url: fileURL) else {
                print("Error: could not create PDFDocument from url")
                return
            }
            document.write(to: filePath)
            print ("success")
        } catch let error {
            print("error: \(error)")
        }
    }

    func getDocumentsDirectory() -> URL {
        let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
        return paths[0]
    }
}

我怀疑该报错和iCloud能力有关，毕竟Files中的文件可能存储在个人iCloud中，但我仅需将文件保存到应用本地文档目录，不需要同步到iCloud。我已经按照Apple文档配置了iCloud能力，报错仍然存在，求解决思路。

解决思路

修复iOS13及以下版本的类型错误
当前iOS13分支里设置的supportedTypes是[kUTTypeImage as String]，但你需要的是PDF文件，应该改成[kUTTypePDF as String]，类型不匹配可能导致文档选择器出现异常。

统一文档选择器的初始化模式
iOS14+你用的是forOpeningContentTypes，该模式默认是查看而非导入操作。如果你需要将文件复制到本地，建议iOS14+也使用forImportingContentTypes，明确导入意图，避免权限或资源访问冲突。修改后代码：

if #available(iOS 14, *) {
    let supportedTypes: [UTType] = [UTType.pdf]
    documentPicker = UIDocumentPickerViewController(forImportingContentTypes: supportedTypes)
} else {
    let supportedTypes: [String] = [kUTTypePDF as String]
    documentPicker = UIDocumentPickerViewController(documentTypes: supportedTypes, in: .import)
}

移除不必要的iCloud配置
既然不需要iCloud功能，直接在Xcode项目的Signing & Capabilities中删除iCloud相关配置项即可。多余的配置反而可能引发不必要的冲突，该报错并非必须依赖iCloud配置解决。

优化文件复制逻辑
当前用PDFDocument.write(to:)保存文件，可替换为FileManager原生复制方法，更直接且避免PDFKit潜在问题：

do {
    try FileManager.default.copyItem(at: fileURL, to: filePath)
    print("文件保存成功")
} catch {
    print("复制文件失败：\(error)")
}

补充取消选择的代理方法
实现documentPickerWasCancelled方法，处理用户取消选择的场景，避免未正确关闭选择器导致的异常：
```
func documentPickerWasCancelled(_ controller: UIDocumentPickerViewController) {
    controller.dismiss(animated: true)
}
```

内容的提问来源于stack exchange，提问作者Nicholas Farmer

如何解决关闭UIDocumentPickerViewController时的报错问题

解决思路 #

解决思路