ios - 无法分配类型为 '(String!, Bool, [AnyObject]!, NSError!)->Void to a value of type UIActivityViewControllerCompletionWithItemsHandler?' 的值

Question

我的项目中有以下几行代码...

@IBAction func shareMeme(sender: UIBarButtonItem) {

    let newMeme = save()
    let memedImage = newMeme.memedImage
    let activityViewController = UIActivityViewController(activityItems: [memedImage], applicationActivities: nil)

    presentViewController(activityViewController, animated: true, completion: nil)

    activityViewController.completionWithItemsHandler = {(type: String!, completed: Bool, returnedItems: [AnyObject]!, error: NSError!) -> Void in

        dispatch_async(dispatch_get_main_queue()){
            self.presentingViewController?.dismissViewControllerAnimated(true, completion: nil)
        }
    }
}

我不断收到编译器错误“无法将类型为‘(String!, Bool, [AnyObject]!, NSError!) -> Void’的值分配给类型为‘UIActivityViewControllerCompletionWithItemsHandler?’的值？”引用以下行代码...

    activityViewController.completionWithItemsHandler = {(type: String!, completed: Bool, returnedItems: [AnyObject]!, error: NSError!) -> Void in

如有任何建议，我们将不胜感激。

Answer 1

您的类型签名与 UIActivityViewControllerCompletionWithItemsHandler 的定义不匹配，即 (String?, Bool, [AnyObject]?, NSError?) -> Void。将您的 ! 替换为 ?，它应该可以正常工作。