Ten IOS interview questions

1. Have you ever used objective-C runtime programming (runtime programming? If you have used it, what have you done with it? Do you still remember the names of the related header files or some methods you are using?

2. Have you implemented multi-threaded core data? Which of the nspersistentstorecoordinator, nsmanagedobjectcontext, and nsmanagedobject need to be created or transmitted in the thread? What policies do you implement?

3. Content of the series starting with core. Whether coreanimation and CoreGraphics have been used. What is the connection between the UI framework and the CA and CG frameworks? What animation or image content has been done with Ca and CG respectively. (If necessary, some quartz content can also be involved)

4. Have you used coretext or coreimage? If you have used coretext or coreimage before, let's talk about your experience using coretext or coreimage.

5. What is the difference and usage between nsnotification and KVO? When should notifications be used and KVO be used? Is there any difference in their implementation? Is it possible to use protocol and delegate (or the delegate array) to implement similar functions? If possible, what are the potential problems? If not, why? (Although protocol and delegate are already broken in the interview ...)

6. Have you used nsoperationqueue? If you have used or understood it, why are you using nsoperationqueue? Describe the differences and similarities between the two and gcd (note: the implementation mechanism and applicability of the two can be described ).

7. Since GCD is mentioned, what should I pay attention to when using GCD and block? Are they the same thing? What are the differences between the behavior and usage of block in arc and the traditional MRC? What do you need to pay attention?

8. Have you done Asynchronous Network processing and communication? If so, can you introduce some specific implementation policies?

9. What do you think is the biggest advantage and disadvantage of objective-C? Are there any available methods to bypass these shortcomings to meet your requirements. If you can, have you considered or practiced some functions of re-implementing oc? If so, what will happen?

10. Have you implemented a framework or library for others' use? If so, let's talk about the experience in building a framework or library. If not, imagine and design the public API of the Framework, and point out what needs to be done and what needs to be paid attention, to make it easy for others to use your framework.