Objective-C

1. Basic use of strings (nsstring,nsmutablestring) string initialization common basic methods: NSString *str = @ "Jacky"; A temporary string NSString *STR2 = [[NSString alloc] initwithformat:@ "%@,20 years", str]; Initialize method

Today is Sunday, want to sleep until 10 o'clock to get up, the result thinks oneself too extravagant, cannot do so, then set the alarm clock to 6:30; The result finally 9:36 woke up, get up, no reason late, OK, even if too tired bar, Sunday forgive

The objective-c is similar in this respect to C + +. Quotation marks are given to local files that are contained locally. (You need to indicate relative paths relative to the existing file). For angle brackets, it is a global path. Quotation marks

Add sub-interface in ScrollView.. directly on the code.Self.navigationController.navigationBar.translucent =NO; Firsttableviewcontroller*FIRSTVC =[[Firsttableviewcontroller alloc] init]; Secondtableviewcontroller*SECONDVC

NsdictionaryImmutable dictionariesWays to create a dictionary How to create a dictionary nsdictionary *dy = [Nsdictionary dictionarywithobject:@ "a" forkey:@ "B"]; Nsdictionary *dy1 = [Nsdictionary dictionarywithobjectsandkeys:@

Objective-c, usually writing OBJC and less used Objective C or OBJ-C, is an object-oriented programming language that expands C. It is mainly used in Mac OS X and GNUstep, which use the OpenStep standard system, and it is the basic language in

Reference counterEach OC object has a reference counter that occupies 4 bytes of storage spaceWhen you use or create an object, the reference counter for the new object defaults to 1Retain: Can make reference counter +1Release: Can be a reference

main functions:UIContol（控件是所有控件的基类 如：（UIButton）按钮主要用于与用户交互，通常情况下我们不会直接使用UIControl，而是子类化它。Common Properties:BOOL enabled 空间默认是启用的，要禁用控件，可以将enabled属性设置为NO,这样将导致控件会略任何触摸控件事件。被禁用后，控件还可以用不同的方式显示自己，such as turning gray is not available. It is done by

Before we analyzed the difference between #include and #import, #import不会引起交叉编译, #import determine that a file can only be imported once, so that there is no problem in recursive inclusion.So what's the difference between #import and @class?(1) In

Association Association refers to associating two objects together so that one of them is part of another object.The affinity attribute is only available on Mac OS X V10.6 and later versions. In addition to the class's definition for adding

This article will not be regularly updated, reproduced please indicate the source http://blog.csdn.net/uxyheaven/article/details/47780957Optimization of conditional statements in Objective-cAsk to judge a nsarray to have value, rigorous wording is

using code to explain how to create a class, the implementation of a class declaration/classI. Declaration of the class//Define an enumeration valueenumcolor{black, white};typedef enumColor Icolor;//Declaration class with

Test Address: http://www.eosgarden.com/en/articles/objc-quizz/take/This is a few days ago friends shared obj-c test questions, a total of 57 questions. Self-Mastery OC I went to do the next test, the result has been a more serious psychological blow,

category (category, Extension)(i) Division of Classifications(2) 1, (named category) categoryCategory: Only new methods can be added and new variables cannot be added. 2. Extensions of (unnamed category) classesExtension://extensions are generally

In the previous three articles about data persistence, we all use files (plist files, database files) that are stored in the document directory. The file mechanism of iOS is a sandbox mechanism where apps can only access files in their own app

Factory method ModeFactory method mode controls the creation of objects, masks the details of object creation, and directly creates the objects we need to be configured.The factory method pattern defines the interface for creating methods, letting

The Get element method for the container (Nsmutablearray, nsmutabledictionary) Objectforkey: Returns the ID type,Convert Nsinteger type, using IntegerValue.// newQuestion is an NSDictionary defined somewhereNSInteger questionId = [[newQuestion

Special attention:Do not use both%@ and self in the description method, use both%@ and self to represent the description method to invoke self, and eventually cause the program to go into a dead loop and call the description method in a loop1.NSLog

OC Block actually functions like C language function pointers, JS in the closure and so on. The code block acts as a variable, with its own variables and scopes.Simply look at the syntax of block and the possible problems:Block Syntax:Block syntax

For objective-c array Nsarray can only save objects, cannot access the base data type, such as Integer int, float float, double-precision floating-point double, char Char, but objective-c in order to be able to save the base data type to an array,