如何创建要保存到新文档的文档范围书签

Question

我有一个基于沙盒文档的Mac应用程序。"我的文档"在用户计算机上合并图像。我想将文档范围的书签保存到文档中使用的图像，以便在关闭并重新打开文档时可以访问该图像。

以下是我创建书签的方法：

 //path is path to an image
 //for a new document docUrl is set to the location where we will save our document
 NSURL * pathUrl = [NSURL fileURLWithPath:path];
 NSError * error;
 NSData * pathBookmarkData = [pathUrl bookmarkDataWithOptions:
                              (NSURLBookmarkCreationWithSecurityScope 
                             | NSURLBookmarkCreationSecurityScopeAllowOnlyReadAccess)
                              includingResourceValuesForKeys:[NSArray arrayWithObject:NSURLPathKey] 
                             relativeToURL:docUrl error:&error];

这会导致以下错误：

Error Domain=NSCocoaErrorDomain Code=260 "The file “Untitled.mydocext” couldn’t be opened because there is no such file." (Collection URL points to a file that doesn't exist) UserInfo=0x608000070800 {NSURL=file:///Users/myname/Pictures/Untitled.mydocext, NSDebugDescription=Collection URL points to a file that doesn't exist}

如何创建要保存到新文档的文档范围书签？

这是我获得路径的方式：

NSArray* fileTypes = [[NSArray alloc] initWithObjects:@"png", @"jpg", @"jpeg", @"bmp", @"gif", @"tif", @"tiff", @"PNG", @"JPG", @"JPEG", @"BMP", @"GIF", @"TIF", @"TIFF", nil];
NSOpenPanel *panel;
panel = [NSOpenPanel openPanel];
[panel setTitle:@"Select Photos"];
[panel setFloatingPanel:YES];
[panel setCanChooseDirectories:YES];
[panel setCanChooseFiles:YES];
[panel setAllowsMultipleSelection:YES];
[panel setAllowedFileTypes:fileTypes];
[panel beginWithCompletionHandler:^(NSInteger result){
    if (result == NSFileHandlingPanelOKButton) {
        NSMutableArray * pathsArray = [[NSMutableArray alloc] init];
        NSArray * urlArray = [panel URLs];
        for (NSURL * url in urlArray) {
            //this is how I get path to image, assume I am not selecting directories
            NSString * path = [url path];
        }
    }
}];

Answer 1

没有必要延迟创建 SSB。此外，传输到路径，然后返回 URL 可能会导致沙盒出现一些问题。尝试使用以下方法：

    // the URLs come back with access to it. they are added to the sandbox by the panel. no need to do anything like start accessing security scoped.
    NSArray * urlArray = [panel URLs];
    for (NSURL *urlToStore in urlArray) {
        // create a SSB out of the URL
        NSError *erroer = nil;
        NSData *bookmarkData = nil;
        bookmarkData = [urlToStore bookmarkDataWithOptions:(NSURLBookmarkCreationWithSecurityScope| NSURLBookmarkCreationSecurityScopeAllowOnlyReadAccess)
                            includingResourceValuesForKeys:nil
                                             relativeToURL:docUrl
                                                     error:&erroer];
        if (erroer) {
            NSLog(@"couldn't create NSURLBookmarkCreationWithSecurityScope with error: %@", [erroer description]);
        } else if ( bookmarkData ) {
            // store the bookmark data either in the document or internally for later persistency
        } else {
            NSLog(@"no error and no bookmarkData: %@", [self description]);
        }
     }