xcode - 类型 'AnyObject' 不符合协议(protocol) 'SequenceType'

Question

func loadThumbnails() {

    let paths = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true)
    let documentsDirectory:NSString = paths[0] as NSString
    var error:NSError?
    let fileManager = NSFileManager()
    let directoryContent:AnyObject = fileManager.contentsOfDirectoryAtPath(documentsDirectory, error: &error)!

    thumbnails = [QSPhotoInfo]()

    for item:AnyObject in directoryContent {
        let fileName = item as NSString
        if fileName.hasPrefix(kThumbnailImagePrefix) {
            let image = loadImageFromDocumentsDirectory(fileName)
            var photoInfo = QSPhotoInfo()
            photoInfo.thumbnail = image;
            photoInfo.thumbnailFileName = fileName
            thumbnails += photoInfo
        }
    }
}

编译错误如下:

Type 'AnyObject' does not conform to protocol 'SequenceType'

这是什么意思？

谁能帮帮我，非常感谢!!!

Answer 1

Apple 在 The Swift Programming Language 中声明:

The for-in loop performs a set of statements for each item in a range, sequence, collection, or progression.

目前，directoryContent 仅符合协议(protocol) AnyObject，因此您不能在其上使用 for 循环。如果你想这样做，你必须做类似下面的事情:

for item in directoryContent as [AnyObject] {
    //Do stuff
}