Can we push notification without using APNs?

问题:

Is it possible to push notification from my 3rd party server directly to my device in Intranet(Wi-Fi)? I have achieved to push notification to the device with the help of APNs, but my requirement to achieve the same without using any external service, say my server and my device is connected to an Intranet, i need to detect the availability of the device in the Intranet and send notification directly. Any idea?? Thanks in advance

回答1:

Well, if—as it sounds—you’re developing an enterprise app that doesn’t have to go through the App Store, there’s nothing to stop you using the iOS 4 multitasking APIs to mimic the way APNS works. Basically how you’d approach it is to register your app as providing VoIP services via the UIBackgroundModes Info.plist key—so the system launches it automatically and keeps it running in the background—and then have the app open a persistent IP connection to your server, via which you can send it whatever notification packets you like. From there, the app can of course use UILocalNotification to alert the user of the notification.

Note that most of this is void if you do have to go through the App Store, unless your app is actually going to provide VoIP services. But since you mention using an intranet, I assume you’ll be developing something in-house and are a member of the enterprise developer program, which allows you to skip the whole App Store thing and use the SDK freely.