how to tell if app was launched from closed or background on iphone?

Hi all is there a specific delegate method which is called when an app is brought to the 开发者_如何学编程foreground from the background on ios? The reason being I want to perform different actions when my app is launched and when it is simply resumed from the background?

Many thanks

Jules

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When you're coming from the background, applicationWillEnterForeground: is called.

When it starts "from closed", applicationDidFinishLaunching: is called.