Sometimes u would need to create some Global Variables in an iPhone Application such that they can be accessed in other implementation class files.
Those Global Variables are created in the AppDelegate. If you want to access it in another file, you have to get the AppDelegate instance before you can read or write the Global Variables. For example, the HelloAppDelegate has a NSString instance variable named as greeting and i want to read it in the HelloViewController.m
HelloViewController.m
// Get the HelloAppDelegate HelloAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate]; // Show the greeting in the log NSLog(appDelegate.greeting);
An alternate way is creating and wiring an app delegate variable in the HelloViewController with the App Delegate Object in the MainWindow.xib.
Thanks Steve for telling me about that.
Done =)
Eureka! 
I’d spent 2 days trying to get this to work, until I came across your post.
What I had been doing was too complex, so it’s great to find the solution was so simple.
Many thanks
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glad to know that it helps =)
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it works 🙂
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good to know that =)
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@Salahuddin, Better to use singleton class.
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@Amin, thanks for your suggestion. =)
@Salahuddin, for your reference
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I guess you wanted to add the code to HelloViewController.m and not HelloViewController.h, right?
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O yes! i didn’t realize that. XD
I have corrected it. Thanks. =)
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What code do you have to put in the app delegate?
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This should help. =)
StackOverflow – setter and getter for NSString declared in AppDelegate
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