[转]四.设计的优先级 3.让您的程序与众不同

Meeting the minimum requirements and delivering features users expect takes you a long way towards producing an application that users in your target market will be eager to buy. Although the top layer of the pyramid represents more work, the result is a user-acclaimed application that takes full advantage of the powerful features of Mac OS X.

满足上面两个要求后，您已经在吸引您的目标客户购买您的产品上前进了一大步。虽然金字塔的上层代表着更多的工作，但是事实是用户喜欢的程序都是充分的利用了Mac OS X的技术的。

Follow the guidelines in this section to produce an application that goes above and beyond users' expectations.

遵守本小节给您的准则可以让您的程序比用户期望的更好。

• Support modelessness.

支持无模式窗口。

As much as possible, avoid forcing the user to complete the current task before they can do anything else. Use sheets and drawers to allow the user more freedom (for more information about sheets and drawers, see “Sheets (Document-Modal Dialogs)” and “Drawers”). If you must use modes in your application, be sure to clearly communicate the current status and make it easy for users to get into and out of a mode.

尽可能的避免强制用户完成当前的任务。使用表单式窗口和抽屉式窗口技术来给用户更多的自由（关于表单式窗口和抽屉式窗口的更多信息，请参考 “表单式窗口（基于文档的模式对话框）” 和 “抽屉式窗口”）。如果您必须在您的程序中使用模式对话框，请清楚的显示当前的状态并且让用户可以很轻松的退出当前的模式对话框。

• Integrate Spotlight.

集成Spotlight。

Spotlight technology allows users to find files anywhere in the system, using criteria they define. Be sure to supply a Spotlight importer if your application uses a custom file format, so users can easily search for the files your application creates. In addition, you should consider using Spotlight technology to provide file system search capabilities in your application. For more information about Spotlight, see “Spotlight.”

Spotlight技术让用户根据自定义的标准可以找到系统中任何位置的文件。如果您的程序使用了自定义的文件格式，请提供一个Spotlight载入器以让用户能够搜索到您的程序创建的文件。此外，您应该考虑使用Spotlight技术在您的程序中提供文件系统搜索功能。关于Spotlight的更多信息，请参考 “Spotlight。”

• Support fast user switching.

支持快速用户切换。

Mac OS X allows multiple users to use a single computer at the same time. With fast user switching, one user's login session is active while the sessions of other users continue to run in the background. Users switch simply by logging in; logging out between users is not required. Applications should take this feature into account to avoid failing in a multiple, simultaneous user environment. If your application relies on exclusive access to resources or assumes there is only one instance of a per-user service running at any one time, be sure to modify the application to safely identify and share system resources. For more information on how to support fast user switching, see Multiple User Environments.

Mac OS X支持多用户同时使用一台计算机。当用户切换时，一个用户的登录会话被激活而其他用户的会话继续在后台运行。登录简化了用户切换，在用户之间登出是没必要的。应用程序必须考虑到这种情况以免在多用户的环境中出问题。如果您的程序依赖于独占资源或者同一时刻只有单独实例在运行，请更改程序从而安全的区分和共享系统资源。关于怎样支持快速用户切换的更多信息，请参考多用户环境。

• Internationalize the user interface.

国际化的用户接口。

The global market for your application is defined by the extent to which it supports locale-specific content and functionality. As you design or revise your application, be aware of differences in language and cultural values and symbols so you can more easily localize your product for specific markets. For more information on internationalization issues, see “Worldwide Compatibility.”

您的程序在全球的市场范围由它所支持的本地化的内容和功能决定。当您设计或者修改您的程序时，要认识到语言、文化价值以及符号之间的差异，从而轻松的将您的程序针对特定的市场本地化。关于国际化问题的更多信息，请参考 “全球范围的兼容。”

• Make your application accessible to users with disabilities.

让有障碍的人士也可以使用您的程序。

To reach the millions of users with disabilities (and to comply with government-mandated accessibility requirements in some markets), you should ensure that your application is accessible. Mac OS X supports accessibility with a range of powerful features, including full keyboard access, speech technologies, and VoiceOver, an integrated accessibility interface to the Macintosh. You should test your application with these features to make sure that the application does not interfere with them and potentially degrade a disabled user's experience. For an overview of accessibility issues, see “Universal Accessibility.”

您应该确保您的程序对于上百万的有功能障碍的人士来说是可用的（也是为了遵守某些市场的政府强制的要求）。Mac OS X具有很多特性来支持这一定，如全键盘访问，语音技术，以及VoiceOver技术。您的程序应该和这些功能一起集成测试，以免妨碍了这些功能并降低有障碍人士的用户体验。关于访问性的问题，请参考“普遍可用性。”

• Strive for high performance and reliability.

努力提高性能和可靠性。

Even a stunning user interface is not likely to be enough to persuade users to continue using an application that performs poorly or behaves in a counterintuitive and unreliable way. Remember that the perception of performance is informed by two things: The speed with which an application processes data and performs operations and the speed with which the application responds to the user. Take advantage of the tools and optimization technologies Mac OS X provides to enhance the performance of your application. Be sure your application responds quickly and keeps the user informed about the progress of lengthy tasks. For more information on some techniques for achieving high performance, see “High Performance.”

即使是出色的用户接口也很难说服用户继续使用一个性能低下的，违反直觉的不可靠的程序。性能由两个东西决定：程序处理数据的速度和程序响应用户的速度。充分利用Mac OS X提供的工具和技术来优化您的程序的性能，确保您的程序能够快速的响应用户，并且在长时间的操作时通知用户操作的进度。关于获得更高性能的技巧，请参考“提高性能。”

Users will be quick to reject your application if it loses or corrupts data or behaves erratically. Build in as many safeguards against data loss as you can and be sure to warn users about potential problems, allowing them to make alternate choices that avoid risky situations. Although unpredictable behavior may not lead to data loss, it can cause users to distrust an application. Make sure the user interface elements in your application behave in an expected and desired way so users can trust your application to do what it promises. For more information on ways to make your application reliable, see “Reliability.”

如果您的程序总是丢失或者损坏数据或者表现异常，用户很快就会拒绝使用您的程序。尽可能的防止数据丢失并且通知用户潜在的问题，允许用户采用替代的方法来避免有风险的操作。虽然不可预期的行为不一定会造成数据的丢失，但是它可能造成用户对程序的不信任。确保您的程序中用户接口上的元素都像用户所期望的那样工作。关于怎么使您的程序更可靠的更多信息，“Reliability.”清参考“可靠性”。

• Surprise and delight.

惊喜和愉悦。

Although less concrete than the other guidelines, this guideline encompasses some of the most important qualities of great software. Fundamentally, users delight in applications that seem to understand them, anticipating their needs and providing them with powerful, intuitive, and streamlined solutions. The best way to follow this guideline is to keep the user's mental model firmly in mind as you design your application (for a discussion of this concept, see “[[macos:human-interface-design-principles#reflectTheUsersMentalModel|Reflect the User’s Mental Model]”). Briefly, you should discover your users' workflow, expectations, and real-world experiences and mirror them in your application's terminology, window layout, menu organization and hierarchy, and toolbar contents.

尽管没有其他的准则具体，该准则仍然强调了优秀软件的一些很重要的特点。基本上，用户会对能够了解他们，能够预见到他们的需求并且提供强大的，直观的和高效的解决方案的程序感到愉快。遵守该准则的最好方式就是当设计您的应用程序时谨记用户的心智模型。简单来说，您应该发掘您的用户的工作流，期望和实际中的经验并把他们映射到您程序中的术语，窗口布局，菜单组织，继承体系以及工具栏的内容等。

取自“http://www.uxguide.net/wiki/macos:Differentiate-your-application”