为什么从不调用NSFilePresenter协议方法? [英] Why do NSFilePresenter protocol methods never get called?

问题描述

我正在尝试监视本地和iCloud目录中的文件更改，并实现了NSFilePresenter协议方法，但是唯一被调用的方法是presentedItemAtURL.

I am trying to monitor file changes in local and iCloud directories and have implemented the NSFilePresenter protocol methods but the only method that gets called is presentedItemAtURL.

我正确的假设是，我应该能够监视本地目录或iCloud目录，并在任何添加，修改或删除目录中文件的过程中得到通知.

Am I correct in assuming that I should be able to monitor a local or an iCloud directory and get notified any time any process adds, modifies or deletes a file in the directory.

这是OS X App的基本代码:

Here is the basic code for the OS X App:

- (void)awakeFromNib {
        _presentedItemURL = myDocumentsDirectoryURL;
        _presentedItemOperationQueue = [[NSOperationQueue alloc] init];
        [_presentedItemOperationQueue setMaxConcurrentOperationCount: 1];
        _fileCoordinator = [[NSFileCoordinator alloc] initWithFilePresenter:self];
}
- (NSURL*) presentedItemURL {
    FLOG(@" called %@", _presentedItemURL);
    return _presentedItemURL;
}

- (NSOperationQueue*) presentedItemOperationQueue {
    FLOG(@" called");
    return _presentedItemOperationQueue;
}

- (void)presentedItemDidChange {
    FLOG(@" called");
    dispatch_async(dispatch_get_main_queue(), ^{
        [self reloadData];
    });
}
-(void)accommodatePresentedItemDeletionWithCompletionHandler:(void (^)(NSError *errorOrNil))completionHandler
{   FLOG(@" called");
    [[NSOperationQueue mainQueue] addOperationWithBlock:^{
        [self reloadData];
    }];
    completionHandler(nil);
}
-(void)presentedSubitemDidChangeAtURL:(NSURL *)url {
    FLOG(@" called");
    dispatch_async(dispatch_get_main_queue(), ^{
        [self reloadData];
    });
}
-(void)presentedSubitemDidAppearAtURL:(NSURL *)url {
    FLOG(@" called");
    dispatch_async(dispatch_get_main_queue(), ^{
        [self reloadData];
    });

}

我知道，很久以前，

推荐答案

但这也许还是有帮助的. NSFilePresenter仅会通知您有关另一个过程的更改，该过程使用NSFileCoordinator对目录或文件进行了更改.如果其他过程(例如iTunes文件共享)在没有NSFileCoordinator的情况下进行更改，则不会通知您.

Long time ago, I know, but perhaps this will still help. NSFilePresenter will only notify you about changes made by another process that makes changes to a directory or file USING AN NSFileCoordinator. If another process (eg: iTunes file sharing) makes changes without an NSFileCoordinator, you won't be notified.

这篇关于为什么从不调用NSFilePresenter协议方法?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！