使用swift在沙盒Mac应用程序中访问文件

Question

我正在开发一个OS X 10.9的应用程序,使用swift,沙盒.

该应用程序需要访问SQLite数据库文件.我让用户用NSOpenPanel选择/打开一个文件.然后,我使用NSUserDefaults保存文件路径供以后使用.

我想每次再次启动应用程序时自动打开此文件.我从NSUserDefault获取存储的路径,但是当我用这个路径打开文件时,我收到一个错误,说我没有权限访问该文件.

(它没有沙盒工作)

它看起来像书签是我的问题的解决方案.

是否有一个很好的教程如何使用swift的书签与osx应用程序？还有其他建议吗？

Answer 1

这是我的回答,我刚刚在Swift 3中工作了一点http://swiftrien.blogspot.com/2015/07/persisting-file-access-rights-between.html

import Foundation
import Cocoa

var bookmarks = [URL: Data]()

func bookmarkPath() -> String
{
    var url = app.applicationDocumentsDirectory
    url = url.appendingPathComponent("Bookmarks.dict")
    return url.path
}

func loadBookmarks()
{
    let path = bookmarkPath()
    bookmarks = NSKeyedUnarchiver.unarchiveObject(withFile: path) as! [URL: Data]
    for bookmark in bookmarks
    {
        restoreBookmark(bookmark)
    }
}

func saveBookmarks()
{
    let path = bookmarkPath()
    NSKeyedArchiver.archiveRootObject(bookmarks, toFile: path)
}

func storeBookmark(url: URL)
{
    do
    {
        let data = try url.bookmarkData(options: NSURL.BookmarkCreationOptions.withSecurityScope, includingResourceValuesForKeys: nil, relativeTo: nil)
        bookmarks[url] = data
    }
    catch
    {
        Swift.print ("Error storing bookmarks")
    }

}

func restoreBookmark(_ bookmark: (key: URL, value: Data))
{
    let restoredUrl: URL?
    var isStale = false

    Swift.print ("Restoring \(bookmark.key)")
    do
    {
        restoredUrl = try URL.init(resolvingBookmarkData: bookmark.value, options: NSURL.BookmarkResolutionOptions.withSecurityScope, relativeTo: nil, bookmarkDataIsStale: &isStale)
    }
    catch
    {
        Swift.print ("Error restoring bookmarks")
        restoredUrl = nil
    }

    if let url = restoredUrl
    {
        if isStale
        {
            Swift.print ("URL is stale")
        }
        else
        {
            if !url.startAccessingSecurityScopedResource()
            {
                Swift.print ("Couldn't access: \(url.path)")
            }
        }
    }

}

func allowFolder() -> URL?
{
    let openPanel = NSOpenPanel()
    openPanel.allowsMultipleSelection = false
    openPanel.canChooseDirectories = true
    openPanel.canCreateDirectories = true
    openPanel.canChooseFiles = false
    openPanel.begin
        { (result) -> Void in
            if result == NSFileHandlingPanelOKButton
            {
                let url = openPanel.url
                storeBookmark(url: url!)
            }
    }
    return openPanel.url
}

要使用此代码,您必须先调用NSOpenPanel,以便用户可以选择允许您访问的文件夹.NSOpenPanel必须存储为书签并保存到磁盘.

import Foundation
import Cocoa

var bookmarks = [URL: Data]()

func fileExists(_ url: URL) -> Bool
{
    var isDir = ObjCBool(false)
    let exists = FileManager.default.fileExists(atPath: url.path, isDirectory: &isDir)

    return exists
}

func bookmarkURL() -> URL
{
    let urls = FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask)
    let appSupportURL = urls[urls.count - 1]
    let url = appSupportURL.appendingPathComponent("Bookmarks.dict")
    return url
}

func loadBookmarks()
{

    let url = bookmarkURL()
    if fileExists(url)
    {
        do
        {
            let fileData = try Data(contentsOf: url)
            if let fileBookmarks = try NSKeyedUnarchiver.unarchiveTopLevelObjectWithData(fileData) as! [URL: Data]?
            {
                bookmarks = fileBookmarks
                for bookmark in bookmarks
                {
                    restoreBookmark(bookmark)
                }
            }
        }
        catch
        {
            print ("Couldn't load bookmarks")
        }

    }
}

func saveBookmarks()
{
    let url = bookmarkURL()
    do
    {
        let data = try NSKeyedArchiver.archivedData(withRootObject: bookmarks, requiringSecureCoding: false)
        try data.write(to: url)
    }
    catch
    {
        print("Couldn't save bookmarks")
    }
}    

func storeBookmark(url: URL)
{
    do
    {
        let data = try url.bookmarkData(options: NSURL.BookmarkCreationOptions.withSecurityScope, includingResourceValuesForKeys: nil, relativeTo: nil)
        bookmarks[url] = data
    }
    catch
    {
        Swift.print ("Error storing bookmarks")
    }

}

func restoreBookmark(_ bookmark: (key: URL, value: Data))
{
    let restoredUrl: URL?
    var isStale = false

    Swift.print ("Restoring \(bookmark.key)")
    do
    {
        restoredUrl = try URL.init(resolvingBookmarkData: bookmark.value, options: NSURL.BookmarkResolutionOptions.withSecurityScope, relativeTo: nil, bookmarkDataIsStale: &isStale)
    }
    catch
    {
        Swift.print ("Error restoring bookmarks")
        restoredUrl = nil
    }

    if let url = restoredUrl
    {
        if isStale
        {
            Swift.print ("URL is stale")
        }
        else
        {
            if !url.startAccessingSecurityScopedResource()
            {
                Swift.print ("Couldn't access: \(url.path)")
            }
        }
    }

}

func allowFolder() -> URL?
{
    let openPanel = NSOpenPanel()
    openPanel.allowsMultipleSelection = false
    openPanel.canChooseDirectories = true
    openPanel.canCreateDirectories = true
    openPanel.canChooseFiles = false
    openPanel.begin
        { (result) -> Void in
            if result == NSFileHandlingPanelOKButton
            {
                let url = openPanel.url
                storeBookmark(url: url!)
            }
    }
    return openPanel.url
}

重新启动应用程序时,您必须调用

let url = allowFolder()
saveBookmarks()

那么您的应用程序将具有与用户选择文件夹时相同的访问级别.希望这有助于某人.

Answer 2

安全范围的书签正是正确的选择。一个好的起点是苹果关于 AppStore 沙箱的文档（其中包括示例代码）和 NSFileManager 的类参考。

然后，您将不会将路径存储在用户默认值中，而是存储书签的二进制数据。