【正文】 f you plan to create games that will be sold via the App Store, rest assured that the Standard Program is the correct choice for you. 3. Select Enroll Now and log in if necessary. 4. You now have another choice: enroll as an individual or as a pany. If you choose Individual, you will not be able to add other programmers or quality assurance members to your account, which is necessary to distribute your application to others during the development and testing process. However, if you select Company, you will be required to provide detailed information about your pany. 5. Continue through the website, selecting the appropriate information, until you arrive at a screen that says “Thank you for submitting your enrollment.””Now you must wait for an from Apple (which may take on the order of a month to arrive). Signing up for the paid developer program will also give you access to beta releases of future versions of the iPhone OS and SDK, but only during the times at which Apple chooses to make them available. It is good to get your paid developer account enrollment going as soon as possible so that it will be available when you actually need it. Application Bundles When you build an application using Xcode, the end result is called an application bundle. In Mac OS X and the iPhone, an application bundle is a special type of directory 2 | Chapter 1: Introduction to the iPhone Download at that holds an executable file and the resources needed to run it. This includes an icon to represent the application, files with special information about the application, and any images or sounds the application uses. In the Finder, an application bundle simply appears as its application icon。 rightclick or Ctrlclick on it and select View Package Contents from the menu to see what’s inside. Although you can’t do this on the iPhone, you can find iPhone applications in the iPhone Simulator. If you have the iPhone SDK installed, 第 4 頁 共 66 頁 you can use Spotlight to search for the file. Show this file in the Finder (don’t try to run it on your Mac), and view its package contents (some of which appears in the following list). A typical iPhone application bundle might have the following structure: Executable (Required.) This is the piled code executable。 for example, , , , and would each contain resources specific to English, French, German, and UK English languages, respectively. (Optional.) You will create this file if you want your application to provide user preference options in the Settings application that es with the iPhone. (Optional.) If you added a file, this image is used to represent the application in the Settings application. The image should be 29 *29 pixels. However, if you do not add this image, the image will be scaled and used automatically. 第 5 頁 共 66 頁 (Optional.) Created by the Interface Builder application, contains code and resources necessary to draw your application as it starts up. More .nib files can be loaded after this one, but it will always be the first in memory. (Optional.) This image is displayed as the application is loading the Main file. It should be full screen, which is 480 *20 pixels on the iPhone. If this image is close to what the user will see when the application is finished loading, the load process will appear to take less time. iTunesArtwork (Optional.) If you are distributing the application outside the App Store, this artwork is used to display your application when loading onto a handset using iTunes. More on this later. As you will see in the next section, when you’re creating your application, Xcode and Interface Builder will create most of these files for you. Xcode and Interface Builder If you are unfamiliar with Xcode, you may be reluctant to learn a new IDE at first. However, the way iPhone development works, you pretty much have to. Fortunately, once you get used to it, you’ll see that Xcode is pretty good at what it does. It has all the features you would expect from an industrystandard IDE: it jumps to the line of pile errors, autopletes plicated API methods, and has integrated SDK references. And it gets better: Xcode supports ondevice debugging, a fullfeatured iPhone Simulator, useful project wizards, refactoring tools, and even direct integration with Subversion revision control repositories. An Xcode project contains all the code, resources, certificates, and configurations you need to create an iPhone application. To get acquainted with the environment, open your Xcode IDE and follow these steps to create a typical “Hello World” application: 1. Open Xcode. 2. Select File → New Project. 3. In the dialog that opens, select iPhone OS, then ViewBased Application (see Figure 11), and click Choose. 4. Name the project “HelloWorld” and click Save. 5. At this point, you can build and run (click the Build and Go icon in the toolbar). The HelloWorld application shows only a blank gray screen when run in the Simulator, as shown in Figure 12. 第 6 頁 共 66 頁 Figure 11. Selecting ViewBased Application Not very interesting yet, is it? Before we go on to make this a proper “Hello World” application, here is a quick rundown of the files that were generated when you created the project: , The class held in these files can be considered the main code entry point of the application. The app delegate controls the main window and main View Controller, and is responsible for setting them up for display. , This class in these files holds the main view, and is responsible for showing the horribly uninteresting gray screen. We will be editing it to say “Hello World” soon. 第 7 頁 共 66 頁 Figure 12. Empty application in the Simulator This Interface Builder file results in a .nib file that is placed in your