1.In Objective-C, a class is itself an object with an opaque type called Class. Classes can’t have properties defined using the declaration syntax shown earlier for instances, but they can receive m

The Objective-C language defers as many decisions as it can from compile time and link time to runtime. Whenever possible, it does things dynamically. This means that the language requires not just

Debug vs. Release BuildsA debug build includes symbols that can be used by a debugger to display your source code when your program stops at a breakpoint and to show you the values of your variabl

Objective-C supports multithreading in applications. Therefore, two threads can try to modify the same object at the same time, a situation that can cause serious problems in a program. To protect s

A snapshot saves the current state of your project or workspace on disk for possible restoration later.Source control repositories keep track of individual changes to files and enable you to mer

To run apps you’re developing on a device, you must set up the device for development. This process involves these main tasks, which you do in Xcode:Obtaining a developer certificate that allo

An iOS device uses one of a set of architectures, which include armv6 and armv7. The Architectures build setting identifies the architectures for which your app is built. You have two options for sp

Built-in product deliveryServer product delivery

Quartz modifies the results of drawing operations according to the parameters in the current graphics state. The graphics state contains parameters that would otherwise be taken as arguments to drawin

When you create a PDF graphics context and draw to that context, Quartz records your drawing as a series of PDF drawing commands written to a file. You supply a location for the PDF output and a def

Note that because a scannerskips whitespace and newlines by default, the loop does no special processing for them (in particular there is no need to do additional whitespace processing to retrieve t

CGLayer objects (CGLayerRef data type) allow your application to use layers for drawing.Layers are suited for the following:High-quality offscreen rendering of drawing that you plan to reu

ou can create a standardized representation of a path using stringByStandardizingPath. This performs a number of tasks including:Expansion of an initial tilde expression;Reduction of e

The Managed Object ModelA managed object model is an instance of NSManagedObjectModel. It’s an object representation of a schema that describes your database, and so the managed objects you use in

-(void) captureScreenImage  {    NSAutoreleasePool *pool = [[NSAutoreleasePoolalloc]init];    if (isPortrait_)    {        UIGraphicsBeginImageContextWithOptions(CGSizeMake(kSmallSrollView

Symmetric KeysSymmetric key cryptography (also called private key cryptography or secret key cryptography) is the classic use of keys that most people are familiar with: the same key is us

Cocoa provides three predicate classes: NSPredicate, and two subclasses of NSPredicate, NSComparisonPredicate andNSCompoundPredicate.Dynamic Property NamesBecause string variables are surr

Understanding the OpenGL ES ArchitectureClient-Server ModelOpenGL ES uses a client-server model, as shown in Figure 1-1. When your application calls an OpenGL ES function, it talks to an O

- (void)navigationController:(UINavigationController *)navigationController      willShowViewController:(UIViewController *)viewController                    animated:(BOOL)animated{   navigat

原来一个label 绘制2次  位置偏离，造成阴影-(void) drawRect:(CGRect)rect {    if ((self.titleString )&&([self.titleString length] > 0))    {                CGContextRef context =UIGraphicsGetC

http://www.360doc.com/content/12/0329/22/6890766_199112306.shtmlhttp://www.360doc.com/content/12/0329/22/6890766_199112306.shtml

iPhone开发之 ARC是什么ARC是什么 ARC是iOS 5推出的新功能，全称叫 ARC(Automatic Reference Counting)。简单地说，就是代码中自动加入了retain/release，原先需要手动添加的用来处理内存管理的引用计数的代码可以自动地ARC是什么ARC是iOS 5推出的新功能，全称叫 ARC(Automatic Refer

Cocoa Touch Layer--AddressBookUI----ABAddressFormatting.h----ABNewPersonViewController.h----ABPeoplePickerNavigationController.h----ABPersonViewController.h----ABUnknownPersonV

因为iOS SDK相对比较底层，所以开发者就得受累多做一些体力活。不过幸运的是，有很多第三方的类库可以用来简化很多不必要的工作.经过作者团队的慎重讨论，他们 评选出了10款能够极大提高iOS开发效率的类库，根据原文作者的评价来看，基本上有了这10款工具，做iOS开发就真的跟泡Cocoa一样了。MBProgressHUD（进度指示符库）地址：https://github.com/jd

果App Store 的应用总下载量近日刚突破 250 亿，并继续上升中。毫无疑问，iOS 开发一直是热门话题，这是一个制造了数亿美元的产业。一个成功的应用，需要良好的规划。在理解应用开发流程中，绘制线框图是规划阶段重要一环，也用于确定 可用性可能存有的问题及技术潜在问题。素描和原型，能让你更好的理解要你的应用程序。如果不是自己的项目，是给客户做的，那也方便和客户解释沟通。如果你是一位设计

因为iOS SDK相对比较底层，所以开发者就得受累多做一些体力活。不过幸运的是，有很多第三方的类库可以用来简化很多不必要的工作。笔者整理了一下在本人学习过程中用到的一些比较有用Objective-C开源类库，既是做一个总结，同时也希望通过这些分享，能提高各位的开发效率。KissXml——xml解析库相关教程：http://www.iteye.com/topic/625849ht

功能测试。单元测试，     单元测试（unit testing），是指对软件中的最小可测试单元进行检查和验证。对于单元测试中单元的含义，一般来说，要根据实际情况去判定其具体含义，如C语言中单元指一个函数，Java里单元指一个类，图形化的软件中可以指一个窗口或一个菜单等。总的来说，单元就是人为规定的最小的被测功能模块。单元测试是在软件开发过程中要进行的最低级别的测试活动，软

Block objects are a C-based language feature that you can use in your C, Objective-C, and C++ code. Blocks make it easy to define a self-contained unit of work. Although they might seem akin to func

CLLocationManager定位经纬度，MKReverseGeocoder地址解析， MKMapView 地图显示 iphonefrom：http://hi.baidu.com/johnzhjfly/blog/item/ae8b7dd139dd7ac8572c84c4.htmlCLLocationManagerCLLocationManager使用步骤1.创建一个CL

原文：http://www.devx.com/wireless/Article/43502/0/page/1 　　【IT168技术】iPhone(手机上网) OS 3.0的最佳功能是GameKit框架，这个框架包括了允许基于蓝牙网络进行通信的API，你可以更轻松地创建点到点的游戏和应用程序。与其它移动平台不一样，在iPhone中使用蓝牙作为一个通信信道比预期的要容易得多

phone的标准推荐CFNetwork C库编程.但是编程比较烦躁。在其它OS往往用类来封装的对Socket函数的处理。比如MFC的CAsysncSocket.在iphone也有类似于开源项目.cocoa AsyncSocket库, 官方网站:http://code.google.com/p/cocoaasyncsocket/ 它用来简化CFnetwork的调用.一.在项目引入ASyncS

今天要调查下日历的机能，以前刚刚接触iOS的第一个项目，和同事们就曾研究过日历的机能，那时候做的东西，多少性能上都有点问题，今天再次调查，开源的优质代码也很多了，整理下给各位需要的同学。devinross/tapkulibrary – GitHub封装了比较多的类，日历只是其中很少的一块，和iOS自带的UI几乎是一模一样。 klazuka/Kal – Git

http://gaohaijun.blog.163.com/blog/static/1766982712010112001652586/要开发地图的朋友或者对scrollview正在专研的朋友，这个应该很有用levelsOfDetail是指，从UIScrollView的1倍zoomScale开始，能够支持细节刷新的缩小级数。每一级是上一级的1/2，所以假设levelsOfDet

一：了解multitasking        background apps(可以在后台运行的任务):             1:play audio              2:get location             3:voip stream             4:request time to finish

//==============================================================================// 资源目录NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:filename];

layoutSubviews在以下情况下会被调用：1、init初始化不会触发layoutSubviews2、addSubview会触发layoutSubviews3、设置view的Frame会触发layoutSubviews，当然前提是frame的值设置前后发生了变化4、滚动一个UIScrollView会触发layoutSubviews5、旋转Screen会触发父UIVie

首先，你得监听键盘的事件，最基本的两个事件：UIKeyboardWillShowNotificationUIKeyboardWillHideNotificationUIKeyboard...iOS 5新增加了一些UIKeyboardDidChangeFrameNotification（will）一般情况下，前两个事件已经可以完成你要做的事情。在你的事

新建 Xcode workspace打开 Xcode ， 选择 File -> New -> Workspace ， 将 Workspace 命名为 Test.xcworkspace ， 并选择合适的目录。新建 Static Library 项目选择 File -> New -> Project ， 项目模板选择 Cocoa Touch Static Library ， 项

iOS开发中我们会遇到程序抛出异常退出的情况，如果是在调试的过程中，异常的信息是一目了然，但是如果是在已经发布的程序中，获取异常的信息有时候是比较困难的。 iOS提供了异常发生的处理API，我们在程序启动的时候可以添加这样的Handler，这样的程序发生异常的时候就可以对这一部分的信息进行必要的处理，适时的反馈给开发者。 不足的地方是，并不是所有的程序崩溃都是由于发生可以捕捉的异常