目录：挑战：翻译Human Interface Guildeline for iOS
翻译：
加载中
当内容加载时，如果界面是空白或静态图片，用户就会以为你的应用程序卡住了。这会导致困惑和失望，并可能导致人们离开你的应用程序。
当处于加载状态时，要把加载正在进行中的信息传达给用户。最起码要展示一个活动转轮表示加载正在进行中。更进一步的话，可以展示出明确的进度，这样用户就可以估计他们将等待多久。
尽快显示内容。不要让人们等到内容加载后才看到他们期望的界面。立即显示界面，并使用占位符文本、图形或动画来标识尚未加载成功的内容。当内容加载成功后再将这些占位符元素替换为内容展示给用户。只要有可能，就在后台预加载即将到来的内容，比如在播放动画或用户在浏览某一级页面或菜单时。
教育或娱乐人们以掩盖加载时间（以免用户在这段加载时间中离开）。可以考虑显示关于游戏玩法、有趣的视频序列或有趣的占位符图形。
自定义加载界面。虽然标准的进度指标通常是可以的，但有时会让人感觉脱离了上下文。这时可以考虑通过自定义动画和与应用程序或游戏风格匹配的元素来设计一种更身临其境的体验。
有关其他指导，请参阅进度指示器。
Loading
When content is loading, a blank or static screen can make it seem like your app is frozen, resulting in confusion and frustration, and potentially causing people to leave your app.
Make it clear when loading is occurring. At minimum, show an activity spinner that communicates something is happening. Even better, display explicit progress so users can gauge how long they’ll be waiting.
Show content as soon as possible. Don’t make people wait for content to load before seeing the screen they're expecting. Show the screen immediately, and use placeholder text, graphics, or animations to identify where content isn't available yet. Replace these placeholder elements as the content loads. Whenever possible, preload upcoming content in the background, such as while an animation is playing or the user is navigating a level or menu.
Educate or entertain people to mask loading time. Consider showing hints about gameplay, entertaining video sequences, or interesting placeholder graphics.
Customize loading screens. Although standard progress indicators are usually OK, they can sometimes feel out of context. Consider designing a more immersive experience through custom animations and elements that match the style of your app or game.
For additional guidance, see Progress Indicators.
