PHPhotoLibrary.requestAuthorization() 在 iOS 9 上不触发授权提示

我有以下功能，显示带有两个不同选项的操作表。目前，唯一实施的选项是标题为“照片”的选项。正确呈现操作表并调用正确的操作。我的问题是，在模拟器和实际设备上，我无法显示请求访问照片库的提示。

PHPhotoLibrary.authorizationStatus() returns .Denied and presents the modal informing the current app does not have access to the photos:

@IBAction func attachPhotoButtonTapped(sender: AnyObject) {
    let actionSheetController = UIAlertController(title: "Images", message: "Select image source...", preferredStyle: .ActionSheet)
    let cancelAction = UIAlertAction(title: "Cancel", style: .Cancel) {
        (action) in
        // ...
    }
    actionSheetController.addAction(cancelAction)

    let takePictureAction = UIAlertAction(title: "Camera", style: .Default) {
        (action) in
        // ...
    }
    actionSheetController.addAction(takePictureAction)

    let choosePictureAction = UIAlertAction(title: "Photos", style: .Default) {
        (action) in
        PHPhotoLibrary.requestAuthorization({(status:PHAuthorizationStatus) in
            switch status{
                case .Authorized:
                    dispatch_async(dispatch_get_main_queue(), {
                        print("Authorized")
                    })
                    break
                case .Denied:
                    dispatch_async(dispatch_get_main_queue(), {
                        print("Denied")
                    })
                    break
                default:
                    dispatch_async(dispatch_get_main_queue(), {
                        print("Default")
                    })
                    break
            }
        })
    }
    actionSheetController.addAction(choosePictureAction)

    presentViewController(actionSheetController, animated: true, completion: nil)
}

我已经“清理”了项目并重置了模拟器设置，但仍然没有收到显示的提示。

发生这种情况是因为CFBundleDisplayNameInfo.plist 文件中的 key 值为空，并且无法构建提示访问照片库权限的警报消息。添加以下行，清理项目并再次构建可以修复问题：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>CFBundleDisplayName</key>
    <string>$(PRODUCT_NAME)</string>
    <!-- More keys and values -->
</dict>
</plist>

谢谢弗拉基米尔·戈尔本科 https://stackoverflow.com/users/5055952/vladimir-gorbenko帮助我解决这个问题。