Pause and Resume iPhone app

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mzichao Author

Level 1

0 points

Pause and Resume iPhone app

Hi,

How does iPhone deal with pause and resume the application?

Thanks.

Mac OS X (10.5.2)

Posted on Jul 24, 2008 3:17 PM

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Answer 1

Top-ranking reply

Mick West

Level 1

60 points

Jul 24, 2008 4:49 PM in response to mzichao

Apps don't really pause when you press the home button. They exit. You have to save your state when you exit, and resume it when it is launched again. That's pretty much app-dependent.

The only time they actually pause is when there is an incoming phone call. When a phone call comes in, your application is sent applicationWillResignActive, and then if the user answers the call you get applicationWillTerminate, and it exits, if they ignore it, then you get applicationDidBecomeActive. Mokeyball's behavior here is to pause the game. Checkword (my app) just ignores the events.

See the "Core Application Architecture" of the "iPhone OS Programming guide"
http://developer.apple.com/iphone/library/documentation/iPhone/Conceptual/iPhone OSProgrammingGuide/ApplicationEnvironment/chapter6_section_2.html#//appleref/doc/uid/TP40007072-CH7-SW2

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Answer 2

hotpaw2

Level 1

75 points

Jul 24, 2008 4:56 PM in response to Mick West

The other reason to pause is if the user taps the sleep/wake button on top. If the app is engaged in any sort of ongoing power hungry behavior (network connections, audio queues, etc.), it might want to pause them.

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Answer 3

mzichao Author

Level 1

0 points

Jul 24, 2008 5:12 PM in response to mzichao

I downloaded many applications from App Store. They all exit after user accepts an incoming call and restarts the app after the call is ended (e.g. Payal and AIM), not resume at the screen where the incoming call came in. Even Contact app does that as well. My app does exactly that. Since they all passed Apple testing and are available on App Store for public download, do I need to worry about the submission over this?

Also, I read that iPhone only allows one application to be run at any given time. Does this correspond to this behavior?

Thanks.

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Answer 4

Jul 24, 2008 5:21 PM in response to mzichao

I think that's pretty much standard behavior. Resuming at the same screen is up to you. Some apps do it, like Safari. It depends on what you want the user experience to be - there is certainly no Apple mandated standard.

And yes, only one app can be run at once with the official SDK.

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Answer 5

sptrakesh

Level 4

1,785 points

Jul 24, 2008 4:12 PM in response to mzichao

It depends upon what you are really after. The application delegate has a applicationWillResignActive method that you may implement to do custom action while "pausing"

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