1.If I call performSelector:
afterDelay: – is the object retained?
Yes the object is retained. It creates a timer that calls a selector on the current thread's run loop.
It may not be 100% precise time-wise as it attempts to dequeue the message from the run loop and perform the selector.
Ball *ball = [[[[Ball alloc] init] autorelease] autorelease];
It will crash because it’s added twice to the autorelease pool and when it dequeued the autorelease pool calls release more than once.
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3. Explain the correct way to manage Outlets memory
Create them as properties in the header that are retained.
In the viewDidUnload set the outlets to nil(i.e self.outlet = nil).
Finally in dealloc make sure to release the outlet.
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4.Whats the NSCoder class used for?
NSCoder is an Abstract Class which represents a stream of data.
They are used in Archiving and Unarchiving objects.
NSCoder objects are usually used in a method that is being implemented so that the class conforms to the protocol.
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5.Whats an NSOperationQueue and how/would you use it?
The NSOperationQueue class regulates the execution of a set of NSOperation objects.
An operation queue is generally used to perform some asynchronous operations on a background thread so as not to block the main thread.
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