facebook ios engineer interview questions

IOS classic interview Summary-memory management, ios questions-memory managementI made a summary based on my own situation. The answer is my summary. If you have any bad answers, I hope to criticize, correct, and communicate. Thank you!Memory Management1. What is ARC?ARC is the automatic reference count of automatic re

using parallelism in Core Data is that each NSManagedObjectContext must be accessed only from the process in which it was created . What is the difference between POST and GET for HTTP?The request for a get type is idempotent according to the HTTP protocol, while the POST request has side effects, that is, get is used to get some resources, and post is used to change some resources, which may create new resources or update existing resources.A POST request is more secure than a GET reques

The interview was asked on the iOS bug, I mentioned the binding click event Bug, but did not tell the problem very clearly, here to clean up the idea.This bug is only available on iOS, including Ihone,ipad, because the iOS browser uses the Safari kernel, so the iOS browser i

the reuse of the cell without confusion. After the data is configured, by updating the constraint, the frame of the last control can be determined only by determining the height that the cell actually needs, and caching it, the next time it is acquired, the judgment exists, and if it exists, it returns directly. Therefore, it is calculated only once.20. How does the UITableView calculate the content height? Why does the proxy method that gets the row height call the data bar several times when

, frequent new/delete is bound to cause memory space discontinuity, resulting in a large number of fragments, so that program efficiency is reduced. For the stack, there is no problem, because the stack is advanced out of the queue, they are so one by one correspondence, so that there will never be a memory block from the middle of the stack poppedAllocation method: The heap is dynamically allocated and there are no statically allocated heaps. Stacks are allocated in 2 ways: static allocation an

Last Updated: 2012: 05: 31Watch the latest IOS interview questions collection, please stay tuned to this blog: http://blog.csdn.net/iukey/article/details/7590557 1. Is object-C inherited? If no, what should I replace it? No, protocol. 2. Is there a private Method for Object-C? What about private variables? No, yes. 3. What is the difference between # im

, and backward 1. A large number of random accesses to data using arrays. If a large number of inserts and deletes are used, a linked list is used. Insert or delete a linked list? Binary Tree? 2. What are the features of queues? 3. What are the usage of const? 4. Static usage? Static Global static local initialization once? If a static variable is defined in the middle of a function OC IOS 1. Function Signature: What should I do when the function nam

Uiimageview in ASIHTTPRequest or sdwebimage? (Put the Uiimageview in the UITableViewCell inside to ask more praise)13. Trouble you to design a simple picture memory buffer (removal strategy is a must say)14. Tell me about your experience using instrument to optimize your animation performance (don't ask me what instrument is)What's Loadview for?Viewwilllayoutsubview you always know.What kinds of queue are there in GCD? Have you built the serial queue yourself? What is the threading model behind

can join, can not delete the original method, but cannot add the instance variableExtension: Extension can add instance variables and methods at the same time, and the method must be implemented, can be regarded as a private classProtocol: A protocol is a list of methods that are shared by multiple classes, and the methods listed in the protocol do not have a corresponding implementationInheritance: Not only can add instance variables and methods, but also can rewrite the method of the original

IOS interview questions1. The answer to the definition of MAX or MIN. cainiao is as follows: #define MAX(X,Y) X>Y ? X : Y Verification:When MAX (1 = 3, 2) is input, the expected result is 2, but the actual result is 0?The answer is as follows: #define MAX(X,Y) ((X) > (Y) ? (X) : (Y)) At this point, most people may say that there is no problem. Why do teachers teach this in college? You can't make a mistake

1. Jesus has 13 disciples, one of whom is a traitor to betray Jesus, please use the rule of exclusion to find the traitor: 13 people sitting around, starting from the first person to cycle off, count to three exclude, the last remaining person is a traitorint people[13] = {1,2,3,4,5,6,7,8,9,10,11,12,13};int count = 0;//is used to record a datagramint number = 13;//Records aliveint i = 0;//record number of people are on the count.while (number > 1) {if (people[i]! = 0) {count++; If a[i] is not re

IOS interview questions: basic concepts of OC 1. What are classes and objects? Class is the abstraction of a group of things with the same features and functions Describes the features and behavior of an object. Class is the abstract object of an object is an instance of a class. 2. Define classes in OC, create objects, and use objects. Classes defined in OC

IOS development Advanced Interview Questions-Role of dealloc under ARC,-arcdealloc In the MRC era, we need to do a lot in dealloc, such as releasing objects; Now we have entered the ARC era. The system has helped us with the release of common objects; Can I rest assured? What should we do under ARC? Opinion: Under ARC, the system can help us release this object

nil. if an object's class does not implement an initializer, the Objective-C runtime invokes the initializer of the nearest ancestor instead. It means that two steps 1 are required to allocate memory 2 for initialization to create an object. 1. allocate memory. sent alloc orallocWithZone: message to the object's class. This is the common [Class alloc]. Or the uncommon [Class allocWithZone]. 2 initialization. You need to call the init Method for initialization. All kinds of init methods that req

After several rounds of interviews, I will summarize the questions frequently asked during the interview: 1. What is the difference between iPad development and iPhone development? A: The development of iPad and iPhone applications use the same SDK. The differences between these sdks are mainly reflected in the hardware and UI operations of devices. (1) device hardware: Because the iPad does not have the p