a)当监视文件夹时,系统永远不会调用requestBadgeIdentifierForURL方法,因此不会设置标记.这里出了什么问题？我是正确的,假设我应该调用这个方法,例如在Finder中移动或滚动受监控的文件夹？顺便说一句,在此上下文中正确调用beginObservingDirectoryAtURL和endObservingDirectoryAtURL方法.

#import "FinderSync.h"

@interface FinderSync ()

@property NSURL *myFolderURL;

@end

@implementation FinderSync

- (instancetype)init {
    self = [super init];

    NSLog(@"%s launched from %@ ; compiled at %s",__PRETTY_FUNCTION__,[[NSBundle mainBundle] bundlePath],__TIME__);

    // Set up the directory we are syncing.
    self.myFolderURL = [NSURL fileURLWithPath:@"/Users/hmaass/Downloads"];
    [FIFinderSyncController defaultController].directoryURLs = [NSSet setWithObject:self.myFolderURL];

    // Set up images for our badge identifiers. For demonstration purposes,this uses off-the-shelf images.
    [[FIFinderSyncController defaultController] setBadgeImage:[NSImage imageNamed: NSImageNameColorPanel] label:@"Status One" forBadgeIdentifier:@"One"];
    [[FIFinderSyncController defaultController] setBadgeImage:[NSImage imageNamed: NSImageNameCaution] label:@"Status Two" forBadgeIdentifier:@"Two"];

    return self;
}

#pragma mark - Primary Finder Sync protocol methods

- (void)beginObservingDirectoryAtURL:(NSURL *)url {
    // The user is now seeing the container's contents.
    // If they see it in more than one view at a time,we're only told once.
    NSLog(@"beginObservingDirectoryAtURL:%@",url.filePathURL);
}


- (void)endObservingDirectoryAtURL:(NSURL *)url {
    // The user is no longer seeing the container's contents.
    NSLog(@"endObservingDirectoryAtURL:%@",url.filePathURL);
}

- (void)requestBadgeIdentifierForURL:(NSURL *)url {
    NSLog(@"requestBadgeIdentifierForURL:%@",url.filePathURL);

    // For demonstration purposes,this picks one of our two badges,or no badge at all,based on the filename.
    NSInteger whichBadge = [url.filePathURL hash] % 3;
    NSString* badgeIdentifier = @[@"",@"One",@"Two"][whichBadge];
    [[FIFinderSyncController defaultController] setBadgeIdentifier:badgeIdentifier forURL:url];
}

#pragma mark - Menu and toolbar item support

- (NSString *)toolbarItemName {
    return @"testfifi";
}

- (NSString *)toolbarItemToolTip {
    return @"testfifi: Click the toolbar item for a menu.";
}

- (NSImage *)toolbarItemImage {
    return [NSImage imageNamed:NSImageNameCaution];
}

- (NSMenu *)menuForMenuKind:(FIMenuKind)whichMenu {
    // Produce a menu for the extension.
    NSMenu *menu = [[NSMenu alloc] initWithTitle:@""];
    [menu addItemWithTitle:@"Example Menu Item" action:@selector(sampleAction:) keyEquivalent:@""];

    return menu;
}

- (IBAction)sampleAction:(id)sender {
    NSURL* target = [[FIFinderSyncController defaultController] targetedURL];
    NSArray* items = [[FIFinderSyncController defaultController] selectedItemURLs];

    NSLog(@"sampleAction: menu item: %@,target = %@,items = ",[sender title],[target filePathURL]);
    [items enumerateObjectsUsingBlock: ^(id obj,NSUInteger idx,BOOL *stop) {
        NSLog(@"    %@",[obj filePathURL]);
    }];
}

@end

b)运行上面的模板时,我在Xcode的日志控制台中收到以下消息：

2015-08-25 15:33:00.300 testfifi[855:8134] Failed to connect
(colorGridView) outlet from (NSApplication) to
(NSColorPickerGridView): missing setter or instance variable
2015-08-25 15:33:00.300 testfifi[855:8134] Failed to connect (view)
outlet from (NSApplication) to (NSColorPickerGridView): missing setter
or instance variable 2015-08-25 15:33:00.321 testfifi[855:8134]
-[FinderSync init] launched from /Users/hmaass/Library/Developer/Xcode/DerivedData/testtest-egudnxkifjxirpbrjkohnatmjuro/Build/Products/Debug/testtest.app/Contents/PlugIns/testfifi.appex
; compiled at 20:38:18

有人可以帮我摆脱这个消息吗？

谢谢！