Visualization of iOS Application States | Hacker News Reader

Visualization of iOS Application States

koduco.com

49 pointsckrumb11 comments

Cute..., and a good start to a UIKit visualization.

By the way, the methods you see in the diagram are to be implemented by a UIApplicationDelegate. Your UIApplicationDelegate class is usually laid out by default in new XCode projects. There are the methods currently documented by Apple.

Monitoring Application State Changes

– application:didFinishLaunchingWithOptions:

– applicationDidBecomeActive:

– applicationWillResignActive:

– applicationDidEnterBackground:

– applicationWillEnterForeground:

– applicationWillTerminate:

– applicationDidFinishLaunching:

Docs here (http://developer.apple.com/library/ios/#documentation/UIKit/...)

Can anyone clarify exactly why a backgrounded application would become suspended? Obviously, it's supposed to occur when the OS becomes low on memory, but does the App's icon actually leave the -- for lack of a better name -- double-tap-dock area?

I've never seen that happen, and nearly every app in my full Springboard is also in the double-tap app switcher.

The switcher is merely a list of recently run applications, not a list of backgrounded applications, which some people have been mistaking it for.

Ahh.. I think perhaps the fact that isn't immediately obvious was somewhat intentional on Apple's part.

They want to make the idea of "running" irrelevant: to the user, it's active or inactive. No need to manage a list of running programs if what is actually running is made invisible and unimportant. Makes it simpler.

Sounds like they may be headed that way with Lion, too - what's seen so far doesn't have the little lights under dock icons that indicate whether the application is actually "open" or not.

Interesting; I hadn't heard that. I feel this trend is good for the future: less things to manage is less that a user can do wrong.

Comparable chart for Android:

http://developer.android.com/reference/android/app/Activity....

That chart has been a life saver for me a couple times.

This is cool – there were two back-to-back one hour lectures on application states at WWDC. Absorbing this graphic is obviously faster and easier.

The image kinda reminds me of an abstract human heart.

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