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iOS Interview Questions : (SET-1)

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Interview Questions :

Q.1) Why using Categories in iOS? write a program to reverse a string.

Q.2) Difference between Protocols, Delegate and Notification.

Q.3) Explain the terms and where it  is used in iOS:
    a. Deligation, and does delegate is retained ?
    b. Informal Protocols, and Designate Initializer.

Q.4) Explain the Memory Management Rules in Objective-C?

Q.5) Using NSURL Class reference, define the meaning of synchronous and asynchronous  request in iOS with a demo example.

Q.6) If I call performSelector:withObject:afterDelay: – Does the object retained?

Q.7) For a given OBJECT of an unknown type, please explain following point in one or two lines:
  •  How will you determine its class?
  •  How will you verify that OBJECT confirms to a given protocol?
  •  How will you verify the response of an OBJECT to a given message?
Q.8) Explain the differences between nib and .xib. What is awakeFromNib?

Q.9) Where does the NSCoder class used?

 Q.10) How to display different image from the server inside the table view?

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