what is apple ios

What is the difference between Retain and Copy in IOS? iosretaincopy 1. Readability: readonly and readwrite@ Property (readwrite,...) valueType value;This attribute is the default attribute of the variable. If you (readwrite and readonly are not used, your variable is the re

throws an exception.This macro validates a parameter for an objective-c method. Simply provide the parameter as the condition argument. The macro evaluates the parameter and, if it is false, it logs a error message that includes the parameter and then raise s an exception.If you define a preprocessing macro, the Ns_block_assertions assertion is forbidden. All the breakpoint macros return void.Assertions

What is the difference between @ synthesize and @ dynamic in iOS? synthesizedynamic OC object-c in order to make java developers accustomed to using the. operation, you can use the @ property variable in the interface class to declare the attribute. However. the attribute declared in h must be in. use @ synthesize or @ dynamic in m (it

1. Thread synchronization is multiple threads accessing the same resource at the same time, waiting for resource access to end, wasting time, inefficient, serial execution of tasksThread Async: Access resources while idle wait while accessing other resources, implement multithreading mechanism, execute task 1.2.3 mode in parallelUse GCD's primary queue. Use Nsoperationqueue to set the maximum number of threads (concurrency) to 1 1.1.1How

throws an exception.This macro validates a parameter for an objective-c method. Simply provide the parameter as the condition argument. The macro evaluates the parameter and, if it is false, it logs a error message that includes the parameter and then raise s an exception.If you define a preprocessing macro, the Ns_block_assertions assertion is forbidden. All the breakpoint macros return void.Assertions

First, create the PCH file. Click Command+n. such as OperationNaming conventions are generally: project name-prefixStep TwoOK, you have finished making the PCH file here. Then you can use it.PCH files generally write data that can be used globally.Like what:The width and color of the screen (no punctuation behind the macro)#define RGB (r,g,b,a) [Uicolor colorwithred: (r/255.0) Green: (g/255.0) Blue: (b/255.0) Alpha: (a)] #define SCREEN_W [ UIScreen mainscreen].bounds.size.width#define Screen_h

What is the difference between ASI and AFN?1. Performance (Focus)* ASI based on the underlying cfnetwork framework* AFN based on nsurlconnection* Operating performance: ASI > ASN2. Processing server data1> AFN: Automatic parsing based on data returned by the server* The server returns JSON data, automatically converted to nsdictionary or Nsarray* The server returns XML data and

According to incomplete local statistics, the recent hotspot for iOS developers remains: "The outlook for the iOS development industry is unclear. "So there are a part of junior developers and expatriates who think this is Apple's pot!" The next step is to take a closer look

XE6 iOS Developer account, Apple certificate (2): About Apple certificate 2014-08-30 21:48Online can find about the Delphi XE series of mobile development related articles very little, this article as far as possible with detailed text content, fool-like expression to tell you the answer you want.1. About the Apple c

Release date:Updated on: Affected Systems:Apple iOS Description:--------------------------------------------------------------------------------Bugtraq id: 66089CVE (CAN) ID: CVE-2013-5133, CVE-2014-1274, CVE-2014-1276, CVE-2014-1277, CVE-2014-1281, CVE-2014-1284, CVE-2014-1285 IOS is an operating system developed by Apple