您必须调用 [[UIApplication sharedApplication] registerForRemoteNotifications]; 才能正确注册远程通知.

You must call [[UIApplication sharedApplication] registerForRemoteNotifications]; to properly register for remote notifications.

为后台使用配置远程通知

您是否已将应用的后台模式配置为接受远程通知?您可以点击:项目名称 -> 功能 -> 背景模式

Have you configured your app's background modes to accept remote notifications? You can do this by clicking: Project Name -> Capabilities -> Background Modes

打开此功能，然后勾选远程通知旁边的框，如下面的屏幕截图所示.

Turn this on and then tick the box beside Remote Notifications as seen in the screenshot below.