• Icon.png – Home screen icon for iPhone 3 (57×57)
• Icon@2x.png – Home screen icon for iPhone 4 (114×114)
• Icon-72.png – Home screen icon for iPad (72×72)

• Icon-Small.png - Settings/Spotlight icon for iPhone 3 (29×29)
• Icon-Small@2x.png – Settings/Spotlight icon for iPhone 4 (58×58)
• Icon-Small-50.png – Spotlight icon for iPad (50×50)

• iTunesArtwork – Icon for iTunes AdHoc distribution (512×512)

Had a request to make the work flow a little easier heres those icons in descending size order

• iTunesArtwork – Icon for iTunes AdHoc distribution (512×512)
• Icon@2x.png – Home screen icon for iPhone 4 (114×114)
• Icon-72.png – Home screen icon for iPad (72×72)
• Icon-Small@2x.png – Settings/Spotlight icon for iPhone 4 (58×58)
• Icon.png – Home screen icon for iPhone 3 (57×57)
• Icon-Small-50.png – Spotlight icon for iPad (50×50)
• Icon-Small.png - Settings/Spotlight icon for iPhone 3 (29×29)

我参加的队伍由8名专业人士组成，出乎我意料的是我们中有6个之前根本没有任何采用敏捷完成工作的经验。这样，我们在其中2名有经验的同伴指导下开 始工作了。一开始，让人高兴的事情并不多，大部分的事情都让人感到沮丧。我们认识到，敏捷并不只是冲刺（Sprint）和没有文档 - 有不少细微之处你得花功夫学才行。

这里说明一下曾经发生过的事情：

开始的麻烦

1. 思维转变

敏捷讲的全是当下的考量、当前的冲刺、当前的用户故事等。当一路走来突然有其他某个故事出现在面前的时候，我们并不会事先考虑事情将如何发展。过去 在瀑布模型里，我们常常是首先考虑整个系统，HLD（高层设计）和LLD（低层设计）是第一步，在继续前进之前，它们必须冻结。

相反，敏捷的内容完全是当前状态和不断改变，要是我们的需求未来会变化，我们的设计也将随之演变；但是我们对于超越当前冲刺的事情并不是特别关注。要接受这一事实得花点时间。

2. 持续换档

敏捷是一个不断变化的环境。“响应变化”是其主导原则之一。为了响应，开发者必须跟市面上的技术保持同步，否则它将让你异常痛苦。

我们曾在项目中使用了一种搜索引擎库，但我们中只有一人对其有了解。由于这个缺陷，我们在估时、结对、站立式会议，以及其他日常实践里都遇到了问题。

我们面对的另一个问题是恰当地进行TDD。从技术观点看，TDD已经有了不少选择。你可以依赖不同的模拟和测试框架，这些往往都是你在瀑布模型里不使用的东西。要是你想采用TDD，那么就必须具备对它们的丰富知识，否则整个过程就不会太顺利。

缓慢地冲刺

1. 测试驱动开发说的是先写测试，然后由测试导出业务逻辑。这是最难适应的事情之一，因为它完全颠覆了你的观念。

   在瀑布模型里，总是代码先完成，然后再进行些测试（通常都有，但并非总是有）；但TDD则完全是红、绿和重构。这种方法要求我们用抽象术语 进行思考，然后由它们演变出具体的事物。由于一开始难以适应，我们往往求助于先写出逻辑，然后确保存在覆盖它们的测试。我把这称为开发驱动测试（DDT） 方法。

   DDT并没有增加太多的意义。假如你知道你的代码将会很好地工作，那为何还要写个测试呢？只是要证明这段代码确实有效？应该不止这一点。的确是这样。例如，写测试可以让你的代码在耦合性方面表现更好，而且还能够为将来的代码变更提供一个巨大的安全网。

2. 在敏捷里，以抽象术语进行思考是开发人员必须具备的技能。在敏捷中我们并不像瀑布模型那样进行预先设计，通过创建抽象和开发工作流，设计到了一定的时候自然就会现身。敏捷中的开发人员必须至少精通基本的设计模式，否则他们将产生一大堆垃圾代码，从中只能得出拙劣的设计。

   TDD在这里对我们大有帮助。它要求我们按抽象术语进行思考。此外，只要我们开始修改测试，我们就必须考虑进行重构，让我们的代码变得更 好。DDT也能帮助我们立即识别任何质量问题，这样它们就能及时地得到修复。这样，我们最终认识到必须抛弃“首先编代码，然后写测试”的套路，后来我们重 新开始采用了TDD方法。

3. 代码质量是团队的职责，团队成员将时不时的重构代码或者可能会重新编写，直到它符合预先制订的标准。我们不要把任何情绪跟我们的代码关联 起来，应该准备不断地抛弃或重写它。遵循Venkat Subramaniam在集体所有制实践方面的建议：“每次执行检入代码操作时，我们都应该致力于改善代码的质量。”

4. 在瀑布模型里，需求是要签字的，有点像血誓，然后你再继续向前移动。但在敏捷里，需求与解决方案同步演变。这帮助我们在前进的过程中让事 情变得越来越清晰，但这也导致系统需要不时的重新设计，在最初的冲刺（1-4）里，这种情况经常会发生。此外，Backlog也能在冲刺的中间改变，因 此，团队应该根据这些变化进行调整，因为在每个冲刺结束时交付可工作的软件是敏捷的座右铭。

5. 结对一开始让人觉得是浪费时间和精力。两人一起在同一故事上进行工作就像是各浪费了一半的时间和精力。而且，多人完成同一故事的不同任务似乎是导致速度下降的原因。

   但是，敏捷中的团队钟情于这种合作做事的方式，不喜欢相同项目组或房间里的人单枪匹马地干活。当团队一起工作时，他们会竭尽所能地把事情向前推进，结果你有极大的可能性是以一致的方式完成事情，而不是最终在多个战线失利。

6. 在采用TDD时，结对的效果最好。Driver和Navigator一起努力开发更好的系统。但如果你是按照DDT的方式进行结对编程， 那它就不是最佳的前进之路。在这种情况下，两个合作者都不会知道该如何前进，例如系统设计应该像什么样子，这样你将得到很多噪音，产生最终必须重写的一堆 源代码文件。

   遵循TDD是最佳的方式，但要是你还没有适应它，你仍然可以结对：利用一块玻璃（白）板，首先画出某个设计流程图，然后其中一个合作者可以编写代码，而另一个则可以编写测试用例。

7. 在演示时交付可工作的软件就像是冲刺的“石蕊测试”。但是，要是软件不是可发布的，你会不会仅仅因为软件可以构建、可工作，而认为一个冲刺就成功了呢？

   当个别故事全部完工而某些没有，这样的冲刺算不算成功呢？那假如冲刺的全部故事基本完成但还有些烦人的小问题呢？

   团队应该关注让整个故事完工，所有问题得到解决，并且满足完工标准；而不是慌慌张张地盯着Backlog马虎了事。一次实施蹩脚的冲刺没有 任何意义，除了在继续前进之前必须将已完成的事情返工。时间常常是一个约束条件，因此根据故事的相对重要程度，团队应该找出一种对他们提议的解决方案更具 质量意义的实施方法。位于Backlog顶端的故事必须尽量以最好的方式开发解决，随着我们逐渐移动到Backlog的底部，对解决方案的质量可能会有些 妥协，但并不是对完工标准而言。对于故事的实现，更好的方式是宁缺勿滥。

8. 站立式会议是铁律。它们意味着成为一个共享平台，不只是你个人的有机会告诉其他人你做过什么和接下来要做什么。人们应该试图去倾听周遭发生的事情，而不只是检查自己的检查表看完成了哪些活动。

   庄严的站立式会议也必须控制在一定时间之内。我们常常会抑制不住开始就某个问题进行讨论的诱惑，但那是必须要避免的。

9. 敏捷团队相当小，在这样一个环境里，人们经常会因为他们在站立式会议上的言论而被他人评判。那么，你就应该说我们在彼此进行脑力激荡或者我昨天什么也没做，再或者是我们重构了代码，而现在我搞不清楚怎么回事了之类的事情吗？这些都只会给新人造成一种尴尬的局面。

10. 计划会议肯定是费脑子和让人精疲力竭的活儿。坐在椅子里4个钟头确定故事点数就像是在玩轮盘赌。这些数字将决定包含在冲刺里的内容，但是怎样在你根本没有经验的时候决定数字呢？你一定会估计错误。

    但这些数字注定就是可能会出错的大致数字，这并不意味着你纯粹是靠运气来开始玩轮盘赌。这些数字在未来的几个冲刺之后将给予你某种指示，告诉你能够完成的工作量。

11. 分配故事点数是一个复杂的任务，应该按阶段完成。团队内部应该首先分析故事，并与产品负责人进行讨论以清晰地了解需求。在得到清晰的视图 之后，就要进行广泛的技术讨论，考虑可以实现的最佳可能解决方案。这步要是完成不好，将导致在故事应该如何实现方面模棱两可，进而导致有缺陷的估计。假 设，如果某个故事接触到了一个新的未探索领域，那么它应该会相当复杂，即便它是一个简单的任务。即使在已知领域，技术解决方案的不同也会导致故事相当复 杂。

    简单干脆的故事最容易被估算，即清楚地知道需求是什么，再加上点应该如何实现的细节。产品负责人无法提供这么干脆的故事。它们只能通过跟团队一起讨论得出来。因此，团队必须花点时间来为下一个冲刺进行调整。

12. 回顾就像是在投票时间被赐予的演讲。我们应该已经完成这个或那个，在下一个冲刺里我们可以完成这个或那个，但是要是这个冲刺里没有接受某 些活儿，什么都不会发生。人们可以表达出对于不同方面的满意与否，但是团队应该着眼于从回顾的观点里得到某些具体任务，否则境况将永远保持下去。

在扎进敏捷之前，你可以做点准备工作：

1. 熟悉市面上的技术，尤其是像JUnit、Fitnesse、EasyMock这样的测试工具。此外，人们应该不断地为更好的解决方案而奋斗，因此出去找找改进流程的新工具和新方法，寻找解决反复出现的问题的新框架或新设计思想和模式。

2. Venkat Subramaniam和Andy Hunt的“高效程序员的45个习惯：敏捷开发修炼之道”是每位涉足敏捷的开发者的必读书籍。

3. 读读Robert C Martin在objectmentor.com上的“Craftsman series”和“Clean Code” 。一开始，你可以不用急着去读它们，但在你碰到一堆麻烦的时候，你就会知道什么时候该去读了。

4. 在站立式会议/计划/讨论，人们评估你建议的时候中保持一颗开放的心。说出你的观点，或者必要的时候要求帮助，你是这个项目的受益人。

5. 测试不仅仅是为了代码覆盖率或质量度量。它们还提供了某种类型的持续保持更新的文档。人们可以先看看测试代码，然后就知道该如何使用这段代码了。

6. 在项目开始就自动化构建过程的所有事情。如果像Checkstyle这样的小事都遗漏了，那么它的结果跟其他模型里的一样，说得多做得少。当你意识到这一点，求助于某种补救手段时，时间往往都太晚了。

学会说A到Z，然后再让你忘记，重新学Z到A往往不会太容易。这会带来些痛苦，但完成转变之后，你就会知道这样做是值得的。

话就说这么多，同志们，上路吧！！:)

查看英文原文：Confessions of A New Agile Developer

登录开发者中心，右侧有个Portal的链接，点击进去就是自己账号的管理中心，初次进入有个向导，可以帮你创建一个开发者证书。最好是下载它的完 整的向导说明书，是一个PDF，7M多，步骤还是挺详细的。但是这本手册在网上没有见过中文版的说明，所以在这里简单介绍一下。

这个开发者中心的用户权限分三种类型：Agent，Admin，Developer。Agent拥有完整的管理权限，Admin也可以管理用户和证 书，Developer只能管理自己的证书和设备。只有Agent有上传软件到App Store的权利。（但是我没有看到添加其它用户的功能，可能需要299美元的账号类型才会有，我自己的账号登录进来就是个Agent了）。

对于个人开发者，你需要完成以下几个过程：

申请一个Development证书 > 设置你的IPhone手机 > 创建一个App ID > 创建并下载安装一个Development Provisioning Profile。经过这几步，你写的程序就可以跑在自己的手机上了（否则只能在虚拟机里面运行）。

然后申请一个Distribution证书 > 创建并安装一个Distribution Provisioning Profile > 编译你的程序 > 就可以发布到App Store了。

下面详细介绍一下：（不知道有没有必要，毕竟买了证书的人都可以下载到这篇很简单的英文文档），所有的介绍以中文版的Mac OS X的菜单和程序名为准

开发者证书安装步骤：

打开应用程序中的“钥匙串访问”，在菜单里点击“证书助理”下面的“从证书代理请求证书”，注意下面不要选中任何行，否则菜单会变。输入自己的注册 Email，常用名称可以写详细一点，比如“Unfish Dev Key”，下面选中“存储到磁盘”，点继续，可能会出现未知错误，多试几次就OK了。然后在浏览器中进入开发者中心的Certificaties导航页 面，在Development页面中最下面选择刚才创建的证书文件，点上传。然后证书就会显示出来，还要再点一下后面的Approve按钮，页面刷新后这 个证书就可以下载了。下来是个cer文件，双击会自动导入，导入类型选择“登录”就可以。

然后是添加自己的手机设备到xcode。把手机连到电脑上，在xcode的windows菜单下打开Organizer，左边的devices下面 会列出你的手机，右边的Identifier项就是你的手机的udid，复制下来，待会要用。如果这个手机还没有设置过作为开发机，这个界面上应该会有两 个按钮，点一下就可以把它设为开发机，在xcode里点Build and go的时候就可以自动的安装你的程序到手机上，不需要通过ITunes了。在开发者中心的左边Devices导航页里点Add Device，起个自己认识的名字，把udid粘贴进去就可以了。（这一步只是开发证书有用，发布证书是不需要这个东西的。）

然后需要创建一个App ID，在开发者中心的App IDs导航页创建一个新的App ID，这个App ID需要跟程序的info.plist里面定义的程序Identifier相对应，如果这里只输入一个*，那么info.plist那里写什么都可以，建议用*。

然后进入开发者中心的Provisioning菜单，在Development页面创建一个新的Provisioning，需要选择所使用的证 书，App ID，和对应的设备，生成以后下载这个provisioning文件，把下载下来的文件拖到Dock上的Xcode的图标上就会自动安装进去。然后退出 xcode重新打开，打开你的项目，打开Project菜单下面的Edit Project Settings，进入Build页面，找到下面的Code Signing Identity，把Any iPhone OS Device项后面选中你的开发者证书，然后就可以把项目的编译目标设为Device（而不是模拟器），试一下Build and Go了。程序应该会编译完并自动安装到你的手机上，并自动启动了。

发布证书安装步骤：

再使用钥匙串访问里面的“从证书代理请求证书”功能，输入自己的Email，名称要写购买证书时登录的公司名或者个人名，下面选中“保存到磁盘”和“让我自己选择私钥”，下一步，把证书保存下来。

进入开发者中心Certificates里面的Distribution页面，选择前面保存的文件上传，然后Approve一下，下载这个证书，双击导入，类型选登录。

进入开心者中心Provisioning里面的Distribution页面，添加新的Provisioning，类型选App Store，（如果选了Ad Hoc，就只有你添加过udid的手机才能安装这个程序了），证书应该是自动出现的，App ID选好，创建完成，下载这个文件，拖到xcode的图标上安装完成。退出xcode再重新打开，否则加载不了你刚刚添加的那个证书，会出现 Provisioning无效的提示。

然后打开你的项目，进入“Edit Project Settings”，进入Configuration页面，选中Release点击下面的Duplicate，复制一个新的配置项出来，命名为 Distribution。然后进入Build页面，顶上的Configuration下拉框选中Distribution，下面的Code Signing Identity里面的Any iPhone OS Device后面对应的值选中你的那个Distribution的证书。然后就可以编译程序了。

如果你之前按照类似这个教程http://www.weiphone.com/thread-222380-1-3.html自己生成过证书并且改过Project Settings和info.plist，需要把这两个地方改回去，否则编译的时候会出现一个warning，CodeSign warning: provisioning is not applicable for product type ‘Application‘ in SDK ‘Device – iPhone OS 2.2′。删掉Project Setting里面的PROVISIONING_PROFILE_ALLOWED = NO和PROVISIONING_PROFILE_REQUIRED = NO，以及info.plist的SignerIdentity，再编译，应该就不会出错了。

程序发布到应用程序商店的步骤：

在开发者中心的Distribution导航里面的App Store页面，在下面的App Store下面的Learn More展开，就可以看到Go to iTunes Connect的链接。进入以后点击Manage My Application，就可以添加自己的程序了。

需要选择程序的语言，国家，介绍等等基本信息，然后下一步上传程序和其它图片。这个地方上传的程序，就是把你的项目编译以后生成的那个.app的目 录直接压缩成zip上传，（这个.app目录里面的任何文件都不可以更改，否则签名就不对了）。你需要准备一张512×512的png图片作为大 Logo，还需要准备5张程序运行的界面截图，在这个页面上挨个选Choose file，再点击upload file，出现对号就没问题了。然后选择程序的价格，默认有很多可以选，free是免费，1是0.99美元，2是1.99美元，诸如此类。如果非免费程 序，你还得准备一份购买协议。

再点下一步，就可以等待程序审核了。

感觉似乎很复杂，不过只要按教程上的步骤一步一步的做，肯定是没有问题的。

原帖地址  http://www.cocoachina.com/bbs/read.php?tid-7923.html

这两天公司让整理文档，一直想写一篇更详细的联机调试的文档，这次刚好是机会
我写的只是联机调试的步骤，并没有深入的去写为什么这么做（关键是我不知道）
希望这篇文章对菜鸟们有帮助，
高手们见了了就不要笑了~~

明天再接着写如何发布程序

必须条件：
99$
(没这个就不用再往下看了)
我的系统是10.5.7   不同版本的系统，可能有点小小的区别
首先登录到
http://developer.apple.com/iphone/index.action

如果已经购买了99$, 登录进去后会看到如下地方(图1)
  

点进去会看到如下界面(图2)
  

这里我要提一下，公司和个人的$99  Team里面的内容是有所不同的(至少我发现有不同)
公司的Team下面可以加入Member  而个人的不能加入Member只能是一个人，不过这里并无大碍，不妨碍我们下面的内容。
点击进入 Certificates 看到如下内容(图3)

点击图中红色部分 会下载下来一个名字为  AppleWWDRCA.cer  的东西
这个是调试发布IPHONE 程序必须的一个东西，这个东西我们只要下载一次就够了，即使你有N个IDP，那么无论是调试程序，还是发布程序，那也只需要一个，后面我们要说到 Distribution页面时，也有这个链接，如果已经下载过，那么就不用再下这个了。(最初因为对这个流程不懂，我下载了N次这个)，
下完之后，点击这个，这个东西就会装到自己的机器上。
打开你的  Keychain Access ，如果dock里面没有到 C盘 ApplicationsUtilities下面去找Keychain Access，中文名字好像叫” 钥匙串…” 打开这个，你会看到如下(图4)

这代表你已经装进去了。

下面，我们打开Keychain的这个菜单(图5)
  

按着下面的图来
(图6)
  

(图7)
  

(图8)
  

然后continute
就会生成一个CertificateSigningRequest.certSigningRequest 的文件，在你的桌面上哦

下一步(图9)：
  

点击Request Certificate(图10)
  

点击Choose File（图11）


选中CertificateSigningRequest.certSigningRequest

点击Choose（图12）
  

点击Submit
(图13)
  

点击Approve
（图14）
  

这时你的证书是牌Pending的状态
刷新一个网页，OK就处于如下状态
（图15）
  

这时点击 Download按钮，会得到一个developer_identity.cer   双击这个文件
（图16）
  

点击OK
这时再打开你的keychain 看看 会是如下结果
（图17）
  

切记这时能看到下面那个 钥匙 状的东西，如果没有这个，是不可能调试的，以前有时，我经常看不到那个 钥匙 状的东西
OK，我们继续

打开Devices 那一项
(图18)
  

点击 Add Devices
（图19）
  

给自己的设备取个名字例如MyIPod
DeviceID 就是自己IPod或IPHONE的机身号（40位），机身号的获取方法有很多，可能通过 xcode 的window->Organizer 来取得
(图20)
  

然后填入表中并点击summit
图21
  

下面我们来搞APPID
图22


点击NewAppID

图23
  

第一处，随便写个名字就行了， 我以AppID为例
第二处，一定要注意了，一定要按着这样的格式写
我这里写的是
com.abc.*
你也可以写成 com.xyz.*    com.google.*  
尽量中间那个变量有点意义，一般情况下是公司的名字。
切记一定要写成这种格式，不然以后会有麻烦
然后submit
图24

继续Provisioning页面
图25
  

点击New Profile
按着我的填一下
图26
  

填完后 Submit
图27
  

Download 你会得到一个 DevProvision.mobileprovision 的文件，这个文件是要装到手机里面的

将这个拖动到organizer  里面
图28
  

拖动后如图29
  

这时打开你的IPOD 你会发现在  设置->通用->描述文件  里面有个东西，那就是你的证书了
然后再双击DevProvision.mobileprovision这个文件，然后你的xcode 就被激活，这时查看C盘
Users用户名LibraryMobileDeviceProvisioning Profiles下面 是不是有了一个
XXXXXX-XXXXXX-XXXXX-XXXXXX.mobileprovision的文件？

下面随便打开一个IPHONE的工程
打开那个工程的plist文件，把Bundle identifier改成如下
图30
  

现在大概你知道 abc 是什么东西了吧
打开这个工程的info
图31
  

然后按着下图改一下设置（切记选中你该选中的那一项）
图32
  

如果你想选中的那一项是灰色的，那么你前面的某些流程一定出了问题

然后还有一处需要确认，如下（图33）
  

请确认，红色是部分是你应该选中的
图34
  

OK
现在已经大功告成了 99.9999%了
选中Device…  Debug    然后 Build and Go
图35
  

程序肯定已经跑在你的机器上了，如果不行，那么重起一下你的IPOD，如果再不行那就重起一下你的电脑，如果再再不行那就自己想办法吧

续
接着如何发布程序
打开Certificicates 的Distribution页面
（图36）
  

点击 Request Certificate按钮(有上面联机调试的步骤这个过程一定很熟了吧)
（图37）
  

选中CertificateSigningRequest.certSigningRequest  文件(这个文件在联机调试的过程中已经生成过了)，
图38
  

选中然后点击Submit
图39
  

点击Appove
图40
  

这时需要刷新一下页面
图41
  

点击DownLoad
会得到一个名为distribution_identity.cer 的文件
双击这个文件，会有如下提示
图42
  

点击OK
然后打开keychain 就会看到如下的图
图43
  

这时你的电脑就已经具备发布程序的证书了

下面打开Provisioning 的Distribution页面
图44
  

点击New Profile
然后按着下图填一下，Profile Name 随便写个名字就行了
图45
  

然后Submit
图46
  

刷新一下
图47
  

OK现在Download ，你会得到一个 Distribution.mobileprovision 的文件
双击这个文件，你的xcode 会被激活
查看C盘
Users用户名LibraryMobileDeviceProvisioning Profiles下面 又多了一个
XXXXXX-XXXXXX-XXXXX-XXXXXX.mobileprovision的文件

现在我们再配置一下xcode
图48
  

打开Configurations 页面
选中Release 然后Duplicate 一下
图49
  

Duplicate之后如下图
图50
  

我们把名字改成Distribution
图51
  

接着我们切换到Build 页面
图52
  

图中1处选中Distribution   2处选中Distribution
然后
图53
  

图54
  

确定图54中，是你应该选的，不然build时会出现签名错误

确定之后，继续
图55
  

选中Device 和 Distribution
OK
图56
  

Build  OK  大功告成了99.9%了

这时如果有签名错误，那一定是你上面某个地方出了问题

成功后
图57
  

其中的iHide 就是我们要上传的东西，在上传之前，我们要把他压缩成 zip 包

现在我们在浏览器中输入
itunesconnect.apple.com
登录一下
图58
  

进入Manage Your Applications
图59
  

点击Add New Application
……………

OK了
后面的不说了~~~

工具下载见原帖地址 http://www.cocoachina.com/bbs/read.php?tid-7923.html

Below is the guide on how to add iAd banner into iPhone app. Guide is based on iAd Programming Guide and WWDC 2010 video.

Add iAd Banner to iPhone App

The first thing you need to do is to add iAd.framework in your Xcode project which is contained in iOS 4 SDK. Also do not forget to add #import <iAd/iAD.h>. Developers can choose between two banners: 320×50 px for portrait and 480×32 px for landscape. The base of banner is ADBannerView, which is subclass of UIView. So the only thing you have to do is to add this view in your control elements hierarchy (you can do this programmatically or using Interface Builder).

Apple recommends to put banner at the bottom or at the top of the window and do not place it on any moving elements like ScrollView or TableView as far as that will decrease shows of banner (and your revenue respectively) and will make it more difficult for user to tap on the ads.

Let’s create a new project in Xcode using View-based Application template and add a banner into it. Name of the app – iAdEx. We are going to edit iAdExViewController.h

and modify viewDidLoad method in iAdExViewController.m

Let’s talk about requiredContentSizeIdentifiers and currentContentSizeIdentifier properties. In the first one you define all types of banners you are going to use. And the second property defines which type of banner you are going to use at the present moment.

Connection issues

Banners are downloaded from the network. What if we have no network connection right now? Or Apple has any issues with ads server? Our ADBannerView will be empty is these cases. It doesn’t look very nice and wastes space on the screen. Apple recommends to do it in this way: when there is no banner for any reason remove it from the screen; when banner is received – show it again.

We have the ADBannerViewDelegate in our class and it can receive messages from banner – bannerViewDidLoadAd (when banner is loaded successfully) and didFailToReceiveAdWithError (when any problems occured). Let’s implement these messages:

It’s time to launch the app and see what we have now:

Tap the banner

And that’s it – we’ve done it in accordance with Apple’s recommendations. When we launch the app we see the banner. If we tap it, then full view of advertisement is shown. But we still have one issue…

Stop & Resume your app

In real app we should stop any application’s activity such as video, audio playback or pause game. In order to solve this task we will create two methods bannerViewActionShouldBegin (when full screen ad is shown) and bannerViewActionDidFinish (when we close ads).

Change Orientation of iAd

What else should we do? We need to make banner change it’s orientation in accordance with iPhone position. First of all we need to change the line where we define types of banners which we will use:

and here are methods for changing orientation:

And here is how it look in a landscape

When device changes orientation we change currentContentSizeIdentifier property of ADBannerView. Now we can see banners in landscape mode too. There is still 50 px offset, but it’s easy to fix.

Apple developers also recommend to write object.delegate=nil; line before deallocating ADBannerView object. In our example it will look like:

Now we have finished with programming part. Good luck with Apple iAd!

Preparing to replace language-pack-zh 1:9.10 (using .../language-pack-zh_1%3a9.10+20090805_all.deb) ...

Unpacking replacement language-pack-zh ...

Preparing to replace language-pack-zh-base 1:9.10 (using .../language-pack-zh-base_1%3a9.10+20090805_all.deb) ...

Unpacking replacement language-pack-zh-base ...

dpkg: error processing /var/cache/apt/archives/language-pack-zh-base_1%3a9.10+20090805_all.deb (--unpack):

trying to overwrite `/usr/share/locale-langpack/zh_TW/LC_MESSAGES/sed.mo', which is also in package language-pack-zh-hant-base

dpkg-deb: subprocess paste killed by signal (Broken pipe)

Preparing to replace language-pack-gnome-zh 1:9.10 (using .../language-pack-gnome-zh_1%3a9.10+20090805_all.deb) ...

Unpacking replacement language-pack-gnome-zh ...

Preparing to replace language-pack-gnome-zh-base 1:9.10 (using .../language-pack-gnome-zh-base_1%3a9.10+20090805_all.deb) ...

Unpacking replacement language-pack-gnome-zh-base ...

dpkg: error processing /var/cache/apt/archives/language-pack-gnome-zh-base_1%3a9.10+20090805_all.deb (--unpack):

trying to overwrite `/usr/share/locale-langpack/zh_TW/LC_MESSAGES/gnome-settings-daemon.mo', which is also in package language-pack-gnome-zh-hant-base

中文的显示是这样：

(正在读取数据库 ... 系统当前总共安装有 123909 个文件和目录。)

正在解压缩 language-pack-gnome-zh-hans-base (从 .../language-pack-gnome-zh-hans-base_1%3a9.10+20090819_all.deb) ...

dpkg：处理 /var/cache/apt/archives/language-pack-gnome-zh-hans-base_1%3a9.10+20090819_all.deb (--unpack)时出错：

正试图覆盖“/usr/share/locale-langpack/zh_CN/LC_MESSAGES/gnome-settings-daemon.mo”，它属于软件包 language-pack-gnome-zh-base

dpkg-deb: 子进程 粘贴 被信号(Broken pipe)终止了

正在解压缩 language-pack-gnome-zh-hant-base (从 .../language-pack-gnome-zh-hant-base_1%3a9.10+20090819_all.deb) ...

dpkg：处理 /var/cache/apt/archives/language-pack-gnome-zh-hant-base_1%3a9.10+20090819_all.deb (--unpack)时出错：

正试图覆盖“/usr/share/locale-langpack/zh_TW/LC_MESSAGES/gnome-settings-daemon.mo”，它属于软件包 language-pack-gnome-zh-base

dpkg-deb: 子进程 粘贴 被信号(Broken pipe)终止了

在处理时有错误发生：

/var/cache/apt/archives/language-pack-gnome-zh-hans-base_1%3a9.10+20090819_all.deb

/var/cache/apt/archives/language-pack-gnome-zh-hant-base_1%3a9.10+20090819_all.deb

E: Sub-process /usr/bin/dpkg returned an error code (1)

类似这样的错误：

dpkg: error processing /var/cache/apt/archives/AAA (–unpack):
trying to overwrite `/usr/lib/BBB‘, which is also in package CCC
dpkg-deb: subprocess paste killed by signal (Broken pipe)
Errors were encountered while processing:
AAA
E: Sub-process /usr/bin/dpkg returned an error code (1)
解决方法：

sudo dpkg -i --force-overwrite AAA

(give full path of AAA), and then run

sudo apt-get -f install

again.

Enough said, the solution is simple. You have to subclass your navigationController’s  popViewControllerAnimated:(BOOL)animated. So create a custom navigationController:

customNavigationController.h

#import

@interface customNavigationController : UINavigationController {}

@end

And a custom “popViewControllerAnimated:(BOOL)animated”, this popViewControllerAnimated-function uses the “UIViewAnimationTransitionCurlDown” when popping from a SettingsTableView.

customNavigationController.m

#import "customNavigationController.h"

#import "SettingsTableController.h"

 

@implementation customNavigationController

 

- (UIViewController *)popViewControllerAnimated:(BOOL)animated

{

if([[self.viewControllers lastObject] class] == [SettingsTableController class]){

 

[UIView beginAnimations:nil context:NULL];

[UIView setAnimationDuration: 1.00];

[UIView setAnimationTransition:UIViewAnimationTransitionCurlDown

forView:self.view cache:NO];

 

UIViewController *viewController = [super popViewControllerAnimated:NO];

 

[UIView commitAnimations];

 

return viewController;

} else {

return [super popViewControllerAnimated:animated];

}

}

@end

Use your custom navigationController in your appDelegate:

customNavigationController *navigationController =

[[customNavigationController alloc] 

initWithRootViewController:rootView];

在实际的开发中，导航器是最重要的容器之一，我们经常要在导航栏中添加各种样式的按钮，添加一个按钮很简单，代码如下图：

UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithTitle:@"Setting" style:UITabBarSystemItemContacts
                                                                 target:self action:@selector(clickSettings:)];         
self.navigationItem.rightBarButtonItem = anotherButton;
[anotherButton release];

其中按钮的样式可以有多种，具体的可以参考：https://developer.apple.com/library/ios/prerelease/#documentation/UIKit/Reference/UIBarButtonItem_Class/

在有些项目中要在右面添加两个按钮，实现的样式如下图：

实现的代码如下图：

UIToolbar* tools = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 150, 45)];
[tools setTintColor:[self.navigationController.navigationBar tintColor]];
[tools setAlpha:[self.navigationController.navigationBar alpha]];
NSMutableArray* buttons = [[NSMutableArray alloc] initWithCapacity:2];

UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd
                        target:self action:@selector(clickSettings:)];

UIBarButtonItem *anotherButton1 = [[UIBarButtonItem alloc] initWithTitle:@"Edit" style:UITabBarSystemItemContacts
                                                        target:self action:@selector(clickEdit:)];
[buttons addObject:anotherButton];
[anotherButton release];
[buttons addObject:anotherButton1];
[anotherButton1 release];
[tools setItems:buttons animated:NO];
[buttons release];
UIBarButtonItem *myBtn = [[UIBarButtonItem alloc] initWithCustomView:tools];
self.navigationItem.rightBarButtonItem = myBtn;

[myBtn release];
[tools release];

一、新建Constants.h文件（文件名根据需要自己取），用于存放全局变量；

二、在Constants.h中写入你需要的全局变量名，例如：

注意：在定义全局变量的时候不能初始化，否则会报错！

三、在需要用到全局变量的文件中引入此文件：

四、给全局变量初始化或者赋值：

五、使用全局变量：和使用普通变量一样使用。

转自：http://www.wuleilei.com/Blog/193

前面写了Mac开发基础：打开一个目录的方法，下面继续，看看如何通过程序得到一个目录的内容。

1, 使用NSFileManager来得到这个目录的内容

NSArray *contentArray = [[NSFileManager defaultManager] 

contentsOfDirectoryAtURL:[[oPanel URLs] objectAtIndex:0] 

//oPanel是上个帖子中的NSOpenPanel对象

includingPropertiesForKeys:[NSArray array]

options:0 

error:nil];

//我们得到一个Array的NSURL

2, 简单显示这个Array中的内容

	for(id innerUrl in contentArray)

{

NSLog([innerUrl absoluteString]);

}

3, 结果

run
[Switching to process 3626]
Running…
2010-06-17 23:32:43.409 XML2HTML[3626:a0f] file://localhost/Users/kingmtn/Downloads/T01/T01n0001.xml
2010-06-17 23:32:43.411 XML2HTML[3626:a0f] file://localhost/Users/kingmtn/Downloads/T01/T01n0002.xml
2010-06-17 23:32:43.411 XML2HTML[3626:a0f] file://localhost/Users/kingmtn/Downloads/T01/T01n0003.xml
2010-06-17 23:32:43.411 XML2HTML[3626:a0f] file://localhost/Users/kingmtn/Downloads/T01/T01n0004.xml
2010-06-17 23:32:43.411 XML2HTML[3626:a0f] file://localhost/Users/kingmtn/Downloads/T01/T01n0005.xml
2010-06-17 23:32:43.411 XML2HTML[3626:a0f] file://localhost/Users/kingmtn/Downloads/T01/T01n0006.xml
2010-06-17 23:32:43.412 XML2HTML[3626:a0f] file://localhost/Users/kingmtn/Downloads/T01/T01n0007.xml

- (void)awakeFromNib

{

[buttonOutlet setPeriodicDelay:2 interval:0.5];

[textFieldOutlet setStringValue:@"Hello world!"];

}

　　使用本越狱工具前请注意！本工具只提供越狱而不提供解锁，有锁版iPhone用户请勿使用，以免造成不良的后果。而目前最新版的Limera1n 为Beta4，主要更新支持MC型号的iPhone 3GS（新Bootrom），修复自身卸载及其他一些BUG。另外目前Limera1n暂时不支持iPod touch 2代的越狱，需要等Geohot测试更新后才能支持。另外目前Limera1n仅支持Windows平台，Mac、Linux或者其他平台的Limera1n需要等待更新才能支持。

　　下面是Limera1n越狱教程：

下载Limera1n Beta3，进入http://limera1n.com/，如无法进入，请借助工具或者避开浏览高峰期进入。

　　获得Limera1n，接着将iPhone/iPod touch/iPad连接到电脑，然后打开Limera1n，见下图：

　　接着点击make in ra1n，然后会出现下面这个界面，提示“hold home+power”

　　按照提示按住电源键+home键不要松手，等待一会，将出现新的提示：“Relase power button”

　　这个时候按照提示松开电源键，但是home键请保持继续按住的状态，然后将会显示“in DFU mode...wait”，进入了DFU模式，见下图：

　　这个时候iPhone/iPod touch/iPad的屏幕上将会出现Limera1n的标志——一滴绿色的雨滴。接着请耐心等待一会，成功的话将会出现以下的界面：

　　Limera1n越狱第一部分完成。接着重启设备，然后在屏幕内找到Limera1n的图标点击进入。

　　在Limera1n里面选择cydia，然后再点击右上角的“Install”，开始进行cydia的下载。注意！此步骤需要无线网络支持。

　　国外用户可直接下载，国内用户如无法下载的，请设置设备内的VPN。

　　cydia下载完成，本次Limera1n越狱工作完成。

　　越狱时及完成越狱后的注意事项：

　　1 越狱的时候请打开iTunes！

　　2 越狱完成后请通过cydia进行SHSH的备份。未备份SHSH的用户，在Cydia的首页会有一个红心标志，点击即可备份。如已经备份过的，则不会出现此标志，并且会在Cydia首页最上方显示“SHSH:iOS 4.1”，表示此设备已经备份过SHSH。

　　3 越狱后如果limera1n和Cydia图标是白色的，无需紧张，重启设备即可。

　　4 越狱后的ipa破解补丁安装，请进入

　　http://apt.weiphone.com/cydia

　　http://app.weiphone.com/cydia/

　　http://apt.weiphone.com/cydia/saurik

　　http://apt.weiphone.com/cydia/bigboss

　　http://cydia.hackulo.us

　　等源，下载安装相应的ipa破解补丁。

TinyUmbrella 4.1.4下载

iTunes10下载

Java运行环境下载

注意事项：

　　1.使用TinyUmbrella之前，请卸载电脑上的Wi-Fi Sync（如果以前安装过）。

　　2.使用本地SHSH恢复过程中可能会有错误提示弹出，但不用担心，固件的确可以完成恢复，如果卡在DFU或黑屏模式无法退出，则可以使用集成的Kick Device Out of Recovery（如下图）按钮来退出恢复模式。

　　3.Mac用户请将App拷备出DMG镜像再运行，否则会收到无尽的密码提示选项。

　　4.必须安装iTunes9.0或以上版本，推荐iTunes10。

　　软件的操作非常简单：

一、备份shsh

　　先将iPhone联机，点击Save My SHSH开始备份。
SHSH文件的位置位于：
Windows XP     C:"Documents and Settings"用户名".shsh            
Windows　　　7 C:"Users"用户名".shsh"                          
Mac　　　　　/Users/用户名/.shsh/                              

注意：
1，在Mac下面文件夹.shsh是隐藏的，要想显示，需在终端中输入：defaults write com.apple.finder AppleShowAllFiles -bool true命令后重启Finder；恢复隐藏，则将true改为false，重启finder。

　　2，从Apple和Saurik取回的SHSH大小不同，但是在恢复时没有影响。

二、自建服务器恢复固件

　　在第一步完成之后，
无需更改hosts，
点击右上角Start TSS Servicer后恢复SHSH对应固件即可。

几点说明：

　　1.Save My SHSH按钮就是备份SHSH的开关。连接iDevice到电脑后，打开TinyUmbrella后直接点击此按钮即可备份SHSH。

　　2.Start TSS Server按钮是在恢复固件时使用的，按下后即可使用本地的SHSH文件来恢复iPhone固件。

　　3.Display SHSHs按钮是用来显示设备是否有相应的SHSH可以下载或者使用，效果如下：

　　4.Advanced Options勾选后会出现ECID、Device/Version和Location三个选项：第一个ECID处可以手动输入ECID码；第二 Device/Version用来强制选择型号和版本；第三个Location是选择SHSH的备份地址，这个要重点介绍一下，选择Apple是从苹果备 份、选择Cydia则是在Cydia中备份、选择Local是备份到本地。没有在本地看到SHSH文件的用户不用担心，默认的备份使用Cydia服务器。

当TinyUmbrella无法识别已经连接到电脑的iPhone、iPad或者iPod touch时，就不能一键备份SHSH了，首先需要使用USBView来查看iPhone的ECID（也可使用ECID读取器或者Auto SHSH Grabber，选择一种习惯的方法即可，不需要每种方法都会）。这里我们使用最可靠的USBView。

首先，按住HOME和Power键十秒左右，iPhone屏幕黑掉，之后读五秒，保持Home键按住并松开Power，当打开的iTunes出现上图中的反映时松开所有按键。

此时，应该有这样的提示。

运行USBView，点击上面的Options。

按图中选中Config Description。

之后按F5刷新，可以看到一个处于DFU模式的iPhone。

这时，在右侧可以找到对应的ECID和iBoot版本。

打开TinyUmbrella并将ECID填入Advanced Options中的ECID框内。

随后，没有越狱过的iPhone需要把Request From一项选择为Apple，然后点击Save My SHSH按键开始保存相应版本的SHSH。（越狱并备份过4.1SHSH的用户可以直接选择Cydia来保存SHSH）。

恢复固件时打开TSS Server选项，这时会自动杀掉iTunes，重新打开后即可正常恢复。

To reduce the overhead of creating this functionality again and again we may encapsulate the common functions in a class. So did I for my applications.

I have created a class named PaginationAgent. After loading records it calls related methods of its delegate which should implement protocol PaginationAgentDeleagte.

Additionally two php files are needed. One to return the total number of records and another one is to fetch the page data. They must be named respectively as

• get_total_number_of_records.php
• get_records.php

Lets see an example.

First, I have created a simple view based project “Pagination” and designed the view as u see:

Create a similar view using Interface Builder

1. Added a button to show previous page data

2. One button to reload the data.

3. Another to show data on next page.

4. Added a UITable which will show the result.

In PaginationViewController.h, imported PaginationAgent.h file and declared:

PaginationAgent* objPagination;

Now lets see how to initialize it. In the viewDidLoad method I initialized this like this:

objPagination = [[PaginationAgent alloc] init];
objPagination.delegate = self;
objPagination.remoteApiBasePath = @"http://your.server/path/to/folder";

remoteApiBasePath must be set to the location where the server side php files are placed.
No trailing slash.

PaginationAgentDelegate protocol declares the following functions to be overridden by the Delegate:

/**
* This method is called when the busystate is changed.
* You can do something like disable/enable the buttons, grayout etc
* based on the isBusy value.
*/
-(void)paginationAgent:(PaginationAgent*)agent updateBusyMode:(BOOL)isBusy;
/**
* Called when total data count is received if shouldReloadAtFirstPage is set NO.
*/
-(void)paginationAgent:(PaginationAgent*)agent totalDataCountReceived:(int)dataCount;
/**
* Called when page data is loaded. You may set your table dataSource here and realod
* reload the table.
*/
-(void)paginationAgent:(PaginationAgent*)agent pageDataReceived:(NSArray*)data;
/**
* Called if server sends malformed data
*/
-(void)paginationAgent:(PaginationAgent*)agent onPaginationServerError:(NSString*)message;
/**
* Called if connection failed. It may occur due to poor or no internet connectivity
*/
-(void)paginationAgent:(PaginationAgent*)agent onPaginationConnectionError:(NSString*)message;

The php files must return data in json format and must use the format as used:

1,'message'=>'Success','data'=>33);
echo json_encode($data);
?>

...
...
$data = array('success'=>1,'message'=>'Got data','data'=>$rows);
echo json_encode($data);

See the attached project for details. The php files are inside the folder “PHPFILES”.

Pagination.zip

1) Integrate iAd 2) ??? 3) PROFIT!

With the iOs SDK 4 now public and the advent of iAds just a few days away, I thought we’d celebrate with a tutorial on how to integrate iAd into your iPhone app!

In this tutorial, not only will we show you how to get started with iAd, but we’ll also show you how to deal with some complex issues you may run into along the way such as:

• Supporting both Portrait and Landscape ads in the same app
• Integrating into a Universal app
• Maintaining backwards compatibility with iOs 3.0
• What to do if you are using a UITableViewController!

We’re actually going to start with where we left off in the How To Port an iPhone Application to the iPad and use the universal app we developed in that tutorial in the starting point.

So grab a copy if you haven’t already, and let’s get to adding some iAds!

Base SDK vs. Deployment Target

The first step to use iAd is to make sure our project has the right Base SDK and iPhone OS Deployment Target selected.

For those of you confused about the difference between the Base SDK and Deployment Target (like I was for quite some time!), here’s what they mean:

• The Base SDK is the version of the SDK you are linking against. Your app can use any classes or functions available in the version of the SDK you choose here – as long as they are available on the actual device the code runs on.
• The Deployment Target is the earliest possible version of the SDK your code can run on. This can be an earlier version than the Base SDK – in fact you often want to set it to be earlier to ensure that as many different versions of the OS can run your code as possible!

The tricky bit is what happens when you want to use a class, function, or framework available in one version of the OS if it’s available, but still work on the old version of the OS if it isn’t. We already did some of this in How To Port an iPhone Application to the iPad, and we’ll do even more in this tutorial!

For this tutorial, we want to set things up so that our code can use stuff available in iOS 4.0 (such as iAd), but still run on as many devices as reasonable (3.0+).

So first let’s set iOs 4.0 as the base SDK. To do this, expand the Targets directory, right click on PortMe, and choose “Get Info”. Click the Build tab, make sure “All Configurations” is selected, navigate to Architectures\Base SDK, and change the value to iPhone Device 4.0.

Then, let’s set iPhone OS 3.0 as the iPhone OS Deployment Target. To do this, still in the Target Build tab, navigate to Deployment\iPhone OS Deployment Target, and change the value to iPhone OS 3.0.

You should now be able to compile and run your app (use the iPhone simulator), and try it out on an iPhone 4 simulator. Once you run your code, in the simulator choose Hardware\Device\iPhone OS 4 and re-run your app. The simulator window will look a little different, and say iPhone 4 in the toolbar, so you’ll know it’s working!

Linking Against the iAd Framework

The next thing we need to do is add the iAd framework to the project. You can do this by right clicking on Frameworks, choosing “Add\Existing Frameworks…”, and choosing “iAd.framework”.

The problem is, if that is all we do our code will break on older devices that don’t have the iAd framework.

You can verify this by trying to run your code in the iPad Simulator 3.2 – boom! The app will crash on startup and you’ll see the following error log:

dyld: Library not loaded: /System/Library/Frameworks/iAd.framework/iAd
Referenced from: /Users/rwenderlich/Library/Application Support/
iPhone Simulator/3.2/Applications/
3ACB1BDA-26F6-43A6-84EA-9FB637B8CDCD/PortMe.app/PortMe
Reason: image not found

To fix this, we need to weak link against the iAd framework. Expand the Targets directory, right click on PortMe, and choose “Get Info”. Click the Build tab, make sure “All Configurations” is selected, and navigate to Linking\Other Linker Flags. Double click on that entry, click the “+” button, and type “-weak_framework iAd”.

Click OK, and then try your app on the iPad simulator again and viola – it should work!

Preparing our XIB

In this tutorial, we’re going to integrate iAd into both the PortMeGameListController and the PortMeGameDetailsController. However, the integration is a bit easier in the PortMeGameDetailsController because it is a subclass of UIViewController, so we’re going to start there first.

Open up PortMeGameDetailsController.xib. You’ll see that all of the controls are children of a single view:

What we’re going to need to do with iAd is scroll an ad view onto the screen when an ad is available, and shrink the rest of the content to fill the remaining space. As currently designed, this isn’t that easy because all of the controls are direct children of the root view. But there’s an easy way to fix it – we’ll simply move the controls into a subview instead!

The easiest way to do this is to drag another view from the library into the XIB, and change its size to be the same as the existing view’s size (320×416). Then drag the existing view as a subview of the new view. When you’re done, it should look like the following:

Then, control-drag from the File’s Owner to the new view (which is now the root view) to connect it to the view outlet. Save your XIB, and run the project and verify that everything still works OK with the details view (in particularly that orientation resizing works correctly). If all works well, we’re one step closer to integrating iAd!

Simple iAd Integration

Ok, now let’s get to the fun part – integrating iAd!

First, make the following changes to PortMeGameDetailsController:

// In the import section
            #import "iAd/ADBannerView.h"
             
            // Modify the PortMeGameDetailsController interface
            @interface PortMeGameDetailsController : UIViewController
            <GameSelectionDelegate, UISplitViewControllerDelegate, ADBannerViewDelegate> {
             
            // Inside the PortMeGameDetailsController interface
            UIView *_contentView;
            id _adBannerView;
            BOOL _adBannerViewIsVisible;
             
            // After the interface
            @property (nonatomic, retain) IBOutlet UIView *contentView;
            @property (nonatomic, retain) id adBannerView;
            @property (nonatomic) BOOL adBannerViewIsVisible;

We first include the iAd headers and mark the view controller as implementing the ADBannerViewDelegate. This way, we can receive events as ads become available or not.

We then declare a property to keep track of the content view that contains all of the controls (basically the inner UIView). We also declare a variable to keep track of our iAd banner view, and whether or not it’s currently visible.

Note that we declare the iAd banner view as an id variable rather than as a ADBannerView. This is because we want to ensure backwards compatibility all the way to OS 3.0, and the ADBannerView class is only available on 4.0+, so we need to weak link against it.

Before we forget, let’s hook up our content view to the new outlet we just made. Make sure you save PortMeGameDetailsController.h, go back to PortMeGameDetailsController.xib, control-drag from the File’s Owner to the inner (second) UIView, and connect it to the contentView outlet.

Then switch over to PortMeGameDetailsController.m and make the following changes:

// In the synthesize section
            @synthesize contentView = _contentView;
            @synthesize adBannerView = _adBannerView;
            @synthesize adBannerViewIsVisible = _adBannerViewIsVisible;
             
            // In the dealloc section
            self.contentView = nil;
            self.adBannerView = nil;

Next, we’re going to add the meat of the code. But there’s a lot of it – so let’s break it down into 6 steps.

1) Add helper functions to get height of iAd banner

- (int)getBannerHeight:(UIDeviceOrientation)orientation {
            if (UIInterfaceOrientationIsLandscape(orientation)) {
            return 32;
            } else {
            return 50;
            }
            }
             
            - (int)getBannerHeight {
            return [self getBannerHeight:[UIDevice currentDevice].orientation];
            }

There are several places in the rest of the code where we’re going to want to know how large the banner view should be given a particular orientation. Currently iAds have two possible sizes: 320×50 for landscape, or 480×32 for portrait. So we simply retrieve the proper height based on the passed in orientation.

2) Add helper function to create the iAd view

- (void)createAdBannerView {
            Class classAdBannerView = NSClassFromString(@"ADBannerView");
            if (classAdBannerView != nil) {
            self.adBannerView = [[[classAdBannerView alloc]
            initWithFrame:CGRectZero] autorelease];
            [_adBannerView setRequiredContentSizeIdentifiers:[NSSet setWithObjects:
            ADBannerContentSizeIdentifier320x50,
            ADBannerContentSizeIdentifier480x32, nil]];
            if (UIInterfaceOrientationIsLandscape([UIDevice currentDevice].orientation)) {
            [_adBannerView setCurrentContentSizeIdentifier:
            ADBannerContentSizeIdentifier480x32];
            } else {
            [_adBannerView setCurrentContentSizeIdentifier:
            ADBannerContentSizeIdentifier320x50];
            }
            [_adBannerView setFrame:CGRectOffset([_adBannerView frame], 0,
            -[self getBannerHeight])];
            [_adBannerView setDelegate:self];
             
            [self.view addSubview:_adBannerView];
            }
            }

This helper function creates an ADBannerView in a manner that is safe to use across multiple OS versions. It uses weak linking and NSClassFromString to check if the ADBannerView class is available – if it is not, the method will return nil and the function will bail.

However, if it is available it creates an instance of the class. It then uses the setRequiredContentSizeIdentifiers to specify what kind of ads this app needs. For our case, our app supports both portrait and landscape modes so it needs both ad options.

It then calls setCurrentContentSizeIdentifier to tell iAd which ad it should display. We simply choose the correct one by looking at the current orientation.

Next, we need to set the frame for the iAd. Note there’s some funky business here – we actually set the frame of the view to be offscreen! This is because we don’t know if an ad is available yet, and we don’t want to display the view until we know one is.

We set our view controller as the delegate so that we can receive notice about iAds being available or not. Then finally we ad the new iAd banner view as a subview of our view!

Note something subtle about the above – we always use message passing syntax rather than dot notation (i.e. [_adBannerView setRequiredContentSizeIdentifiers:...] instead of _adBannerView.requiredContentSizeIdentifiers = …). This is again to make sure everything runs fine on OS 3.0+.

3) Add function to size views correctly

- (void)fixupAdView:(UIInterfaceOrientation)toInterfaceOrientation {
            if (_adBannerView != nil) {
            if (UIInterfaceOrientationIsLandscape(toInterfaceOrientation)) {
            [_adBannerView setCurrentContentSizeIdentifier:
            ADBannerContentSizeIdentifier480x32];
            } else {
            [_adBannerView setCurrentContentSizeIdentifier:
            ADBannerContentSizeIdentifier320x50];
            }
            [UIView beginAnimations:@"fixupViews" context:nil];
            if (_adBannerViewIsVisible) {
            CGRect adBannerViewFrame = [_adBannerView frame];
            adBannerViewFrame.origin.x = 0;
            adBannerViewFrame.origin.y = 0;
            [_adBannerView setFrame:adBannerViewFrame];
            CGRect contentViewFrame = _contentView.frame;
            contentViewFrame.origin.y =
            [self getBannerHeight:toInterfaceOrientation];
            contentViewFrame.size.height = self.view.frame.size.height -
            [self getBannerHeight:toInterfaceOrientation];
            _contentView.frame = contentViewFrame;
            } else {
            CGRect adBannerViewFrame = [_adBannerView frame];
            adBannerViewFrame.origin.x = 0;
            adBannerViewFrame.origin.y =
            -[self getBannerHeight:toInterfaceOrientation];
            [_adBannerView setFrame:adBannerViewFrame];
            CGRect contentViewFrame = _contentView.frame;
            contentViewFrame.origin.y = 0;
            contentViewFrame.size.height = self.view.frame.size.height;
            _contentView.frame = contentViewFrame;
            }
            [UIView commitAnimations];
            }
            }

This is a helper function we can call to make sure our views are in the right position. If ads are available, we want the ad banner view to be at the top of the screen and the content view shrunk a bit to fill the rest of the area. If ads are not available, we want the ad banner view offscreen and the content view as large as the entire view here.

And that’s exactly what the above function does. It looks long, but is fairly simple and self-explanatory. Note that we wrap the resizing code in an animation block to make things look awesome.

4) Call createAdView in viewDidLoad

- (void)viewDidLoad {
            [self createAdBannerView];
            }

We want to create our ad view as soon as our view is loaded, even if we aren’t ready to display it quite yet.

5) Call fixupAdView in viewWillAppear and willRotateToInterfaceOrientation

- (void) viewWillAppear:(BOOL)animated {
            [self refresh];
            [self fixupAdView:[UIDevice currentDevice].orientation];
            }
             
            - (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
            [self fixupAdView:toInterfaceOrientation];
            }

We need to fix up our ad view in viewWillAppear, because the device may have changed orientations in the time between when our view was visible last and now. And we obviously need to change it upon rotation as well!

6) Implement ADBannerViewDelegate

#pragma mark ADBannerViewDelegate
             
            - (void)bannerViewDidLoadAd:(ADBannerView *)banner {
            if (!_adBannerViewIsVisible) {
            _adBannerViewIsVisible = YES;
            [self fixupAdView:[UIDevice currentDevice].orientation];
            }
            }
             
            - (void)bannerView:(ADBannerView *)banner didFailToReceiveAdWithError:(NSError *)error
            {
            if (_adBannerViewIsVisible)
            {
            _adBannerViewIsVisible = NO;
            [self fixupAdView:[UIDevice currentDevice].orientation];
            }
            }

Now that we have our helper functions, implementing the ADBannerViewDelegate methods are quite simple. We simply toggle whether the ad banner view should be visible or not, and call fixupAdView.

Done!

And that’s it! Compile and run your project, and you should see ads appear correctly in both portrait and landscape mode.

And best yet – if you run the code on an iPad or iPhone 3.0 device it will work just fine as well, but without ads!

UITableView integration

Well that worked great for our details controller, but we want it in our list controller too!

The problem is our list controller is a UITableViewController. Unfortunately, it seems like the best way to deal with this situation is to convert your UITableViewController to a normal UIViewController and then proceed similarly to the way we did above. So here are all of the gory steps:

1) Create a XIB for PortMeGameListController

Go to File\New File, choose User Interface and View XIB, make sure Product is iPhone, and click Next. Name the XIB PortMeGameListController.xib and click Finish.

Open up the XIB, click on the File’s Owner, and in the fourth tab of the Attributes Inspector change the class to PortMeGameListController.

Then drag a UIView into the current UIView (so there are 2, just like we did before), and add a UITableView to the inner view. When you’re done it should look like this:

2) Make some changes to PortMeGameListController

Inside PortMeGameListController.h:

// Change the interface declaration
            @interface PortMeGameListController : UIViewController <UITableViewDelegate, UITableViewDataSource> {
             
            // Add inside class
            UITableView *_tableView;
            UIView *_contentView;
             
            // Add after class
            @property (nonatomic, retain) IBOutlet UITableView *tableView;
            @property (nonatomic, retain) IBOutlet UIView *contentView;

Inside PortMeGameListController.m:

// In synthesize section
            @synthesize tableView = _tableView;
            @synthesize contentView = _contentView;
             
            // In dealloc section
            self.tableView = nil;
            self.contentView = nil;

Don’t forget to save the files!

3) Hook up outlets

Now go back to PortMeGameListController.xib and connect the first view to the view outlet, the second to the contentView outlet, and the third to the tableView outlet.

Also control-drag from the tableView back to the File’s Owner and set it as the delegate and datasource.

4) Set the NIB name for PortMeGameListController in MainWindow

Open MainWindow.xib and MainWindow-iPad.xib, expand the Navigation Controller, select “Port Me Game List Controller”, and change the nib name to PortMeGameListController.

5) Compile and test to make sure everything works as usual

At this point, compile and run your code and make sure everything works as it usually does – but now you’re using a UIViewController rather than a TableViewController, and you have a XIB laid out in a nice way to use iAds!

6) Follow the steps from the previous section

Now you’re exactly where we were in the previous section with a view controller – so follow the same steps to integrate in this view!

Done!

If all goes well, you should be able to compile and run your project and see advertisements at the top of your table view!

Where To Go Now?

Here is a sample project with all of the code we’ve developed in the above tutorial.

Now you should know how to integrate iAds into your projects – no matter what OSs you wish to support for your app! I’d love to hear your experiences with iAds and how well they are working (or not) for your app!

- (void)setBackgroundImage {
NSLog(@"setting bg image");
UIImageView *customBackground = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"background.jpg"]];
self.background = customBackground;
[customBackground release];
[self addSubview:background];
NSLog(@"Added background subview %@", background);
[self sendSubviewToBack:background];
}

- (void)loadView {
UIImageView *contentView = [[UIImageView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
[contentView setImage:[UIImage imageNamed:@"Default.png"]];
[contentView setUserInteractionEnabled:YES];
self.view = contentView;
[contentView release];
}

This video was embedded using the YouTuber plugin by Roy Tanck. Adobe Flash Player is required to view the video.
The finished product is shown below.

Rather than sticking with stock components included in Interface Builder, this demonstration shows a simple technique that gives your app a more professional look. As a developer, it can be difficult to create nice looking graphics for your app. Hiring a designer can quickly exceed the budget. However, creating some nice looking graphics is certainly achievable as a beginning designer. In addition to picking up some new great skills, a polished off UI can lend more creditability to your app and provide an overall better user experience.

In the demo, Photoshop Elements is used, which is 80 bucks at adobe.com with a mail-in rebate. To get started, create a new image with these values:

• Width: 80 pixels
• Height: 40 pixels
• Background Contents: Transparent

Select a foreground color from the toolbar, as shown below:

Now select the gradient button, as shown below:

With the gradient selected, swipe from bottom to top on your image. This should produce a gradient color. Now choose File and “Save for Web”. You’ve just created the image we’ll use in our tableview. Let’s switch over to Xcode and implement the image.

In Xcode, we start by creating a navigation based application.

Once the application has been created, add the newly created image by right clicking the Resources folder then “Add” and “Existing Files”, as shown below:

The following code snippet creates two views. Both are then added to the cell’s view. Because the label, which is a view, is added as the last view, we need to ensure its background is transparent (clearColor). Otherwise, it will cover part or all (depending on the size we set) of our background image. Thinking about what this stack of layers will look like, below is a screenshot of the same scenario in Interface Builder:

From the screenshot, you can see the cell’s view owns the imageview and label. Although closer to the bottom, the label is actually top most to the user, hence the reason we need its background to clear.

Let’s take a look at the implementation in Xcode, which is all done in the UITableView delegate method cellForRowAtIndexPath:.

UIImage *image = [UIImage imageNamed:@"gradientcolor.png"];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
imageView.contentMode = UIViewContentModeScaleToFill;
cell.backgroundView = imageView;
[imageView release];
UILabel *label = [[UILabel alloc] init];
label.text = @"testing colors";
label.frame = cell.bounds;
label.backgroundColor = [UIColor clearColor];
label.textAlignment = UITextAlignmentCenter;
[cell addSubview:label];
return cell;

In the above snippet, we create an image object using the image we added to our app bundle. Next, we create a UIImageView object with the newly created image. The image view will be assigned to our cell’s background view. The backgroundView will retain an instance of the imageView. Therefore, we release our instance, as follows:

[imageView release];

If we had not released our instance, we’d have two instances of the imageView in memory and thus a memory leak. Moving on down in the code, we create an instance of a label. We set the label’s size to cover the entire cell. The label’s background is set to clear or transparent so it doesn’t hide the cell’s background image. Our assigned text is centered and finally, we add the label to the cell’s view, making it the top most view in the cell.

So, in myTableViewController I created custom init function:

- (id) initWithFrame:(CGRect)frm {
if ((self = [super initWithStyle: UITableViewStylePlain])){
self.tableView = [[UITableView alloc] initWithFrame:frm style:UITableViewStylePlain];
}
return self;
}

Obviously, you can use default or your own init function or avoid passing frame argument and hardcode dimensions right here, but the magical line is:

self.tableView = [[UITableView alloc] initWithFrame:CGRectMake(x, y, width, height) style:UITableViewStylePlain];

Well, at least it worked for me.

At this point, you need to have a working UITableView-based application. If you aren’t at this point, you’ll need to take a few steps back and check with the official Apple iPhone SDK documentation.

The simplest case is adding an accessory icon to the right of all cells in the table. To do this, edit the source file of the table view you want to change and add the following method:

- (UITableViewCellAccessoryType)tableView:(UITableView *)tv accessoryTypeForRowWithIndexPath:(NSIndexPath *)indexPath
{
   return UITableViewCellAccessoryDetailDisclosureButton;
}

Yeah, that’s a keyboard-full, but it’s not that bad. Because your table view class is the delegate of your actual table view, implementing this method of the UITableViewController class will automatically affect the cells in your table. No other changes are needed to make this work. Very cool.

If you don’t want to show the accessory image for every cell in the table, you’ll need to implement some logic in this method that takes the NSIndexPath parameter (which tells you which row in which section is being asked about) and responds appropriately.

There are three standard accessory images that can be used by this method. Each image is shown below with the matching UITableViewCellAccessoryType (the example uses shows a Disclosure indicator image because it returns UITableViewCellAccessoryDisclosureIndicator.

Disclosure indicator

UITableViewCellAccessoryDisclosureIndicator
Used to indicate that tapping the cell will slide in a new table view one level down in the hierarchy.

Detail disclosure button

UITableViewCellAccessoryDetailDisclosureButton
This button indicates that tapping the cell will reveal a detail view of that item.

Checkmark

UITableViewCellAccessoryCheckmark
Indicates that a row has been selected by the user.

Nothing

UITableViewCellAccessoryNone
This is the default value for the cell accessory indicating that no accessory should be shown.

This isn’t a brain surgery level Tech-Recipe and this information is, of course, covered in the official documentation, but I keep forgetting the method name and knew it would be easier to lookup here than in the docs. I hope someone else finds it helpful, too.

It is really easy to customize your UITableViews. I'll show you how to completely customize the appearance of UITableViews without overriding or subclassing and without the need for any tricky hackery.

Make my table pretty

The core of most iPhone applications is the UITableView. To make your iPhone application stand out, the simplest way is to make your UITableView look good.

Customizing your UITableView can be really easy. You don't need custom drawing code. You don't need subclasses of anything. Cocoa Touch provides all the drawing capability you need, all you have to do is use the right classes in the right ways and provide the layout.

The sample application

The approach I'll show you will turn the table on the left into the table on the right:

Left: a default UITableView with three rows. Right: the same table view after customization.

How to fail at UITableView customizing

Coming from Mac OS X made it harder for me — UITableView needs to be customized in a very particular way and structurally, it is very different to Mac OS X's NSTableView and NSCell drawing.

The following are all really bad ways to customize a table (even though you can make it work):

• Subclassing UITableView to customize drawing
• Subclassing UITableViewCell to customize drawing
• Creating your own array of UITableViewCells and returning these instead of using dequeueReusableCellWithIdentifier:

About the second point: it is okay to customize UITableViewCell — but you shouldn't really use it for drawing. The UITableViewCell class is more of a controller class — it handles behaviors and layout, not drawing. You can customize UITableViewCell to load a specific contentView (and do the custom drawing there).

That last point (that you should always use dequeueReusableCellWithIdentifier:) is only peripherally related to drawing but it will significantly slow your drawing down if you avoid the normal cell queuing architecture.

How to succeed at UITableView customizing

There are only a few points to understand related to table drawing.

First: the UITableView does not itself draw anything except the background. To customize the background of a UITableView, all you need to do is set its backgroundColor to [UIColor clearColor] and you can draw your own background in a view behind the UITableView.

Second: The tableHeaderView (and the table footer and section headers and footers) need not be just a title. You can insert your own view, with its own subviews in the table header, giving layout and custom drawing freedom.

Third: UITableViewCell is composed of 5 different subviews. Customizing the right subview is the secret to good UITableViewCell drawing. The subviews are:

1. backgroundView — the entire background of the row (including what looks like the UITableView's background in UITableViewStyleGrouped style tables.
2. selectedBackgroundView — replaces the backgroundView when the row is selected.
3. image — a customizable image (not actually a subview) at the left of the cell.
4. accessoryView — a customizable view at the right of the cell.
5. contentView — a customizable view between the image and the accessoryView (technically, it extends behind the image).

You can customize any of these (except image which must be a UIImage) using your own custom drawn views.

However, since the pixel size of the table never changes, it is often easiest just to use UIImageViews for each of them. Then you can take highly complex views drawn in separate programs, cut them into the 5 necessary pieces and let the automatic caching of UIImage's named image cache manage your memory for you.

There is an argument against drawing your views in code and that is that the iPhone's drawing is not nearly as fast as Mac OS X. Operations like gradients and multiple overlapped components can really tax the iPhone.

Custom drawing code is a good choice for simple and flat colour drawing. In most other cases — as in this post — I recommend you use UIImageView to draw your views in a table.

Implementation

With all custom drawing handled by UIImageView, that still leaves some work to do. You must handle all layout and configuring of views.

Configuration of the UITableView and layout of the table header

As an example of what that means, have a look at the viewDidLoad method for this post:

- (void)viewDidLoad
{
//
// Change the properties of the imageView and tableView (these could be set
// in interface builder instead).
//
tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
tableView.rowHeight = 100;
tableView.backgroundColor = [UIColor clearColor];
imageView.image = [UIImage imageNamed:@"gradientBackground.png"];
//
// Create a header view. Wrap it in a container to allow us to position
// it better.
//
UIView *containerView =
[[[UIView alloc]
initWithFrame:CGRectMake(0, 0, 300, 60)]
autorelease];
UILabel *headerLabel =
[[[UILabel alloc]
initWithFrame:CGRectMake(10, 20, 300, 40)]
autorelease];
headerLabel.text = NSLocalizedString(@"Header for the table", @"");
headerLabel.textColor = [UIColor whiteColor];
headerLabel.shadowColor = [UIColor blackColor];
headerLabel.shadowOffset = CGSizeMake(0, 1);
headerLabel.font = [UIFont boldSystemFontOfSize:22];
headerLabel.backgroundColor = [UIColor clearColor];
[containerView addSubview:headerLabel];
self.tableView.tableHeaderView = containerView;
}

This method handles the configuration of the tableView (setting the backgroundColor, rowHeight and sets an image behind the table) but also creates its own layout for the table header.

The layout of the header here is for the table's header view. You can include a custom header for every table section by implementing the UITableViewDelegate method tableView:viewForHeaderInSection:. There are equivalent properties and methods for the table and section footers.

It is possible to handle this type of layout in Interface Builder and load the XIB files for this type of layout. Sadly though, on the iPhone, reading loading lots of views from XIB files is slow (I suspect this is due to slow reading from the Flash memory) and doesn't always allow configuration of every property.

For this reason, I normally sketch my views in Interface Builder and then manually recreate the same thing in code. That's what I've done here: picking coordinates for the headerLabel that looks balanced in the view.

Cell backgrounds

The cell background needs to incorporate the tops and bottoms of table "sections". For this reason, the backgroundView and selectedBackgroundView normally need to be set on a row-by-row basis.

In your tableView:cellForRowAtIndexPath: method where you are configuring the cell for a given row, this code will handle that behavior:

UIImage *rowBackground;
UIImage *selectionBackground;
NSInteger sectionRows = [aTableView numberOfRowsInSection:[indexPath section]];
NSInteger row = [indexPath row];
if (row == 0 && row == sectionRows - 1)
{
rowBackground = [UIImage imageNamed:@"topAndBottomRow.png"];
selectionBackground = [UIImage imageNamed:@"topAndBottomRowSelected.png"];
}
else if (row == 0)
{
rowBackground = [UIImage imageNamed:@"topRow.png"];
selectionBackground = [UIImage imageNamed:@"topRowSelected.png"];
}
else if (row == sectionRows - 1)
{
rowBackground = [UIImage imageNamed:@"bottomRow.png"];
selectionBackground = [UIImage imageNamed:@"bottomRowSelected.png"];
}
else
{
rowBackground = [UIImage imageNamed:@"middleRow.png"];
selectionBackground = [UIImage imageNamed:@"middleRowSelected.png"];
}
((UIImageView *)cell.backgroundView).image = rowBackground;
((UIImageView *)cell.selectedBackgroundView).image = selectionBackground;

Layout within the contentView

Layout of elements within the contentView need only be set on construction of the contentView (not on a row-by-row basis).

Sadly, laying out UILabels in the contentView (like the "Cell at row X." and "Some other infomation." lables in this example) is a little verbose.

The following code is run immediately after the allocation of the UITableViewCell to position the "Cell at row X." label:

const CGFloat LABEL_HEIGHT = 20;
UIImage *image = [UIImage imageNamed:@"imageA.png"];
//
// Create the label for the top row of text
//
topLabel =
[[[UILabel alloc]
initWithFrame:
CGRectMake(
image.size.width + 2.0 * cell.indentationWidth,
0.5 * (aTableView.rowHeight - 2 * LABEL_HEIGHT),
aTableView.bounds.size.width -
image.size.width - 4.0 * cell.indentationWidth
- indicatorImage.size.width,
LABEL_HEIGHT)]
autorelease];
[cell.contentView addSubview:topLabel];
//
// Configure the properties for the text that are the same on every row
//
topLabel.tag = TOP_LABEL_TAG;
topLabel.backgroundColor = [UIColor clearColor];
topLabel.textColor = [UIColor colorWithRed:0.25 green:0.0 blue:0.0 alpha:1.0];
topLabel.highlightedTextColor = [UIColor colorWithRed:1.0 green:1.0 blue:0.9 alpha:1.0];
topLabel.font = [UIFont systemFontOfSize:[UIFont labelFontSize]];
//
// Create a background image view.
//
cell.backgroundView = [[[UIImageView alloc] init] autorelease];
cell.selectedBackgroundView = [[[UIImageView alloc] init] autorelease];

In my mind, it seems like there should be a more efficient way to do this. I hold out the possibility that there is.

This code spends most of its time working out where the label should be placed. It needs to go right of the image, left of the accessoryView, middle of the row but above the "Some other information." label.

Other adornments

The accessoryView is just a UIImageView. The cell.image is set as a property. These are extremely simple additions but they make the table cells far more impactful.

Conclusion

You can download the EasyCustomTable project as a zip file (60kb).

The code includes a #define at the top that allows you to toggle the custom drawing on and off.

None of this is particularly revolutionary (it is all in the iPhone documentation) but it is still easy to miss the properties and methods that make it easy.

This does require custom images. If you've never drawn anything, now is a good time to learn inkscape (it's free and very good for the price). You could also use Adobe Illustrator but if you have that much money, pay an artist to draw it for you.

Layout of the content in code is probably the weakest part of the approach I've presented. To make it easier, you can pre-layout everything in Interface Builder and copy the layout into code. For complicated layouts, you could even try using nib2objc to convert your XIB files to code automatically (although I've never done this, I'm just mentioning nib2objc because the idea is so cool).

Convert int to NSString

When you use UIDatePicker in your app you will a tumbler that lets users select a date that you may use in other parts of your app.

In order to use UIDatePicker you will need to implement the UIPickerViewDelegate delegate and then add a UIPicker to your subview. To retrieve the date that the user inputs you can use the target-action pattern to assign a method to execute once the user has picked a date. See the video below:

Here is the code from the example:

Implement the UIDatePickerView Delegate

The first thing we needed to do was indicate that our view controller would be acting as a delegate for the UITextField. To do this you simply need to declare it in the interface file:

#import <UIKit/UIKit.h>
//UIPicker requires an object that adopts the UIPickerViewDelegate protocol
@interface DatePicker : UIViewController<UIPickerViewDelegate> {
}
@end

Add the UILabel and UIDatePicker Objects

This part is straightforward enough: you essentially create a label and a date picker and add them both to the view controller’s subview collection. This is the typical pattern used to build up a view in code.

#import "DatePicker.h"
@implementation DatePicker
UILabel *label;
UIDatePicker *datePicker;
- (void)viewDidLoad {
[super viewDidLoad];
//Create label
label = [[UILabel alloc] init];
label.frame = CGRectMake(10, 10, 300, 40);
label.textAlignment = UITextAlignmentCenter;
//Use NSDateFormatter to write out the date in a friendly format
NSDateFormatter *df = [[NSDateFormatter alloc] init];
df.dateStyle = NSDateFormatterMediumStyle;
label.text = [NSString stringWithFormat:@"%@",
[df stringFromDate:[NSDate date]]];
[df release];
[self.view addSubview:label];
[label release];
// Initialization code
datePicker = [[UIDatePicker alloc] initWithFrame:CGRectMake(0, 250, 325, 250)];
datePicker.datePickerMode = UIDatePickerModeDate;
datePicker.hidden = NO;
datePicker.date = [NSDate date];
[datePicker addTarget:self
action:@selector(changeDateInLabel:)
forControlEvents:UIControlEventValueChanged];
[self.view addSubview:datePicker];
[datePicker release];
}
- (void)dealloc {
[datePicker release];
[label release];
[super dealloc];
}
@end

Implement Your Action Method

This is the method that you assigned to the UIControlEventValueChanged event above using the target-action pattern.

- (void)changeDateInLabel:(id)sender{
//Use NSDateFormatter to write out the date in a friendly format
NSDateFormatter *df = [[NSDateFormatter alloc] init];
df.dateStyle = NSDateFormatterMediumStyle;
label.text = [NSString stringWithFormat:@"%@",
[df stringFromDate:datePicker.date]];
[df release];
}

How this works is that when the user stops manipulating the tumbler an event called UIControlEventValueChanged occurs. Since we assigned the changeDateInLabel method as an action for this event the code in that method will execute updating the date in the label.

Time To Take Action!

Learning how to program is 5% reading and 95% action so the best way to learn is to do it yourself. Create a simple iPhone app that uses the date picker code.

Let us know how it goes in the comments below!