出自UXGuide.net

应用程序图标

Application Icons

An application icon is an icon users put on their Home screens and tap to start an application. This is a place where branding and strong visual design should come together into a compact, instantly recognizable, attractive package.

应用程序图标是用户会放在其主屏幕的图标，点击可启动应用程序。在这里，品牌宣传和大量的视觉设计将浓缩于一个精简、可立即识别且引人注目的整体。

Users choose which application icons they want to display on their Home screens, so you should design an icon that is:

用户选择希望显示在其主屏幕上的应用程序图标，因此你应当将图标设计得：

• Attractive, so users feel compelled to keep it on their Home screens

具有吸引力，这样用户觉得必须要将其留在主屏幕上

• Distinctive, so users can easily find it among all other icons

具有独特性，这样用户可以在其他图标中轻松将其找到

Try to balance eye appeal and clarity of meaning in your icon so that it’s rich and beautiful, but still conveys the essence of your application’s purpose. Also, it’s a good idea to investigate how your choice of image and color might be interpreted by people from different cultures.

尽量在吸引眼球和含义清晰之间找到平衡，使你的图标在丰富多彩的同时能够表达应用程序的目的。而且，研究其他不同文化背景下的人们对你选择的图像和颜色的理解也是不错的办法。

When a user decides to display your application icon on the Home screen, iPhone OS automatically adds some visual effects so that it coordinates with the built-in icons. Specifically, iPhone OS adds:

当用户决定在主屏幕上显示你的应用程序图标时，iPhone OS 会自动添加一些视觉效果以与内置的图标保持协调。具体包括：

• Rounded corners
  圆角
• Drop shadow
  投影
• Reflective shine
  光照反射

For example, Figure 11-1 shows a simple icon as it might be provided by an application.

例如，图 11-1 展示了一个应用程序提供的简单图标。

Figure 11-1  A simple application icon before it is displayed on a Home screen
图 11-1 没有显示在主屏幕上的简单的应用程序图标

Figure 11-2 shows the same icon as it is displayed on a Home screen by iPhone OS.

图 11-2 展示了同样的图标由 iPhone OS 显示在主屏幕上的样子

Figure 11-2  A simple application icon displayed on a Home screen
图 11-2 显示在主屏幕上的简单的应用程序图标

Application icons that include a discernible background look best on the Home screen. This is primarily because of the rounded corners iPhone OS adds: uniformly rounded corners ensure that all the icons on a user's Home screen have a consistent appearance that invites tapping. If you create an icon with a black background that disappears when it's viewed on the Home screen, users don't see the rounded corners. Such icons often don't look tappable and tend to interfere with the orderly symmetry of the Home screen that users appreciate.

包含清晰背景的应用程序图标在主屏幕上看上去效果最佳。这主要是因为 iPhone OS 所添加的圆角：统一的圆角确保用户主屏幕上的所有图标都具有统一的外观。如果你创建了背景为黑色的图标，那么它在主屏幕上显示时就会消失，用户不会看到圆角。这种图标起来像不可点击的，尤其会打乱用户本主屏幕的次序结构

To ensure that your icon can take advantage of the visual enhancements iPhone OS provides, produce an image in PNG format that:

为了确保你的图标能够得益于 iPhone OS 提供的视觉增强，应当将图像处理成 PNG 格式并满足下列条件：

• Measures 57 x 57 pixels, with 90 degree corners (if the image measures other than this size, iPhone OS scales it)
  尺寸为 57 x 57 像素，90 度直角（如果图像尺寸不同，iPhone OS 将进行缩放）
• Does not have any shine or gloss
  未包含光泽或玻璃效果
• Does not use alpha transparency
  未使用 Alpha 透明

Name your icon file Icon.png and place it at the top level of your application bundle. To learn more about the contents of the application bundle, see “The Application Bundle” in iPhone Application Programming Guide.

将图标文件命名为 Icon.png 并放在你应用程序包的最顶层。要进一步了解关于应用程序包的内容，参见 iPhone Application Programming Guide 中的“The Application Bundle”。

When you submit your application, you must include a 512 x 512 pixel version of your application icon for display in the App Store. Although it’s important that this version be instantly recognizable as your application icon, it should be subtly richer and more detailed. In other words, you should not simply scale up your application icon to create an icon for the App Store.

当提交应用程序时，你必须包含你应用程序图标的一个 512 x 512 像素版本，以用于显示在 App Store 中。尽管这个版本能够被立即识别为你的应用程序图标的确非常重要，但它仍应当相比而言更加丰富细致。换句话说，你不应只是简单地将应用程序图标放大来创建 App Store 图标。

You must also provide a 512 x 512 pixel version of your application icon if you’re developing an application for ad-hoc distribution (that is, to be distributed in-house only, not through the App Store). In the ad-hoc case, name the icon file iTunesArtwork (no file extension) and place it at the top level of your application bundle. This icon identifies your application in iTunes.

如果你开发应用程序是为了私下分发（而不是通过 App Store）的话，你也必须为应用程序图标提供一个 512 x 512 像素的版本。在这种情况下，将图标文件命名为 iTunesArtwork（没有文件扩展名）并将其放在应用程序 bundler 的顶端。