cracking the interview

冒泡

1.raywenderlinch iOS Interview Questions

• Explain method swizzling. When you would use it?
• Take three objects: a grandparent, parent and child. The grandparent retains the parent, the parent retains the child and the child retains the parent. The grandparent releases the parent. Explain what happens. 

• What happens when you invoke a method on a nil pointer? 

• Give two separate and independent reasons why retainCount should never be used in shipping code. 
• Explain your process for tracing and fixing a memory leak. 
• Explain how an autorelease pool works at the runtime level. 
• When dealing with property declarations, what is the difference between atomic and non-atomic? 
• In C, how would you reverse a string as quickly as possible?
• Which is faster: to iterate through an NSArray or an NSSet? 
• Explain how code signing works.
• What is posing in Objective-C? 
• List six instruments that are part of the standard. 
• What are the differences between copy and retain?
• What is the difference between frames and bounds? 
• What happens when the following code executes? Ball *ball = [[[[Ball alloc] init] autorelease] autorelease]; 
• List the five iOS app states. — Almost no one gets this question right. Normally I have to give an example, such as background state, for them to know what I am talking about.
• Do you think this interview was a good representation of your skills as a developer? 

autorelease 的對象何時被釋放？