cocoa - 基于 Cocoa 文档的应用程序中文档的默认保存位置

我创建了一个基于 Cocoa 文档的图片绘制应用程序。我希望在保存/另存为对话框中使用我的应用程序创建的新文档的默认位置应该在 ~/Pictures/MyAppName/目录中。

我怎样才能做到这一点？

我或多或少地尝试了 Ole 在下面建议的内容，但它不起作用。这是我对 prepareSavePanel 的实现。我究竟做错了什么？

- (BOOL)prepareSavePanel:(NSSavePanel *)savePanel
{
    if ([self fileURL] == nil) {
        //new, not saved yet
        [savePanel setExtensionHidden:NO];

        //set default save location
        NSArray *paths = NSSearchPathForDirectoriesInDomains(NSPicturesDirectory, NSUserDomainMask, YES);

        if ([paths count] > 0) {
            NSString *userPicturesPath = [paths objectAtIndex:0];
            NSString *myDirPath = [userPicturesPath stringByAppendingPathComponent:@"MyAppName"];


            //create directory is it doesn't already exist
            NSFileManager *fileManager = [NSFileManager defaultManager];
            BOOL isDir;
            BOOL useMyAppDir = NO;
            if([fileManager fileExistsAtPath:myDirPath isDirectory:&isDir]){
                if (isDir) {
                    useMyAppDir = YES;
                }
            } else {
                //create the directory
                if([fileManager createDirectoryAtPath:myDirPath withIntermediateDirectories:YES attributes:nil error:nil]){
                    useMyAppDir = YES;
                }
            }

            if (useMyAppDir) {
                NSURL * myAppDirectoryURL = [NSURL URLWithString:myDirPath];
                [savePanel setDirectoryURL:myAppDirectoryURL];
            }
        }
    } else {
        [savePanel setExtensionHidden:[self fileNameExtensionWasHiddenInLastRunSavePanel]];
    }

    return YES;
}

最佳答案

在您的 NSDocument 子类中，覆盖 -prepareSavePanel:

- (BOOL) prepareSavePanel:(NSSavePanel *)savePanel
{
    // Set default folder if no default preference is present
    NSDictionary *userDefaults = [[NSUserDefaults standardUserDefaults] persistentDomainForName:[[NSBundle mainBundle] bundleIdentifier]];
    if ([userDefaults objectForKey:@"NSNavLastRootDirectory"] == nil) {
        NSArray *picturesFolderURLs = [[NSFileManager defaultManager] URLsForDirectory:NSPicturesDirectory inDomains:NSUserDomainMask];
        if ([picturesFolderURLs count] > 0) {
            NSURL *picturesFolderURL = [[picturesFolderURLs objectAtIndex:0] URLByAppendingPathComponent:@"MyAppName"];
            [savePanel setDirectoryURL:picturesFolderURL];
        }
    }
    return YES;
}

关于cocoa - 基于 Cocoa 文档的应用程序中文档的默认保存位置，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/5729363/