Navigation

People tend to be unaware of an app’s navigation until it doesn’t meet their expectations. Your job is to implement navigation in a way that supports the structure and purpose of your app without calling attention to itself. Navigation should feel natural and familiar, and shouldn’t dominate the interface or draw focus away from content. In iOS, there are three main styles of navigation.

当app不满足用户的期望时用户才意识到需要app的导航。你的工作是要实现导航来支持app结构，同时不要引起用户注意。导航应该看起来自然和熟悉，不要在界面中占主要位置或者转移内容的焦点。在iOS，主要有3种样式的导航。

Hierarchical navigation.Make one choice per screen until you reach a destination. To go to another destination, you must retrace your steps or start over from the beginning and make different choices. Settings and Mail use this navigation style.

层级导航。你只能在每个屏幕做一个选择到达一个目的地。为了到达另外的目的地，你必须重新追随你的步骤或者从起点重新开始，做出不同的选择。设置和邮箱使用这种导航样式。

Flat navigation.Switch between multiple content categories. Music and App Store use this navigation style.

平行导航。在多个内容目录之间转换。Music和AppStore使用这种导航样式。

Content-driven or experience-driven navigation.Move freely through content, or the content itself defines the navigation. Games, books, and other immersive apps generally use this navigation style.

内容驱动或者体验驱动导航。在内容见只有移动，或者内容本身定义导航。游戏，books和其他沉浸式app基本使用这种导航方式。

Some apps combine multiple navigation styles. For example, an app that uses flat navigation may implement hierarchical navigation within each category.

一些app结合了多种导航样式。例如，一个app使用平行导航也许在各个类别中实现层级导航。

Always provide a clear path.People should always know where they are in your app and how to get to their next destination. Regardless of navigation style, it’s essential that the path through content is logical, predictable, and easy to follow. In general, give people one path to each screen. If they need to see a screen in multiple contexts, consider using an action sheet, alert, popover, or modal view. To learn more, seeAction Sheets,Alerts,Popovers, andModality.

一直提供一个清晰的路径。用户应该一直知道他们在你app的什么地方和怎么到达他们的下一个目的地。忽略导航样式，内容的路径应该是有逻辑的、可预测的、容易跟随的。一般，给用户提供一个到每个屏幕的路径。如果他们需要在多个环境看到一个屏幕，考虑使用action sheet、提醒、弹出框、或者模态视图。To learn more, seeAction Sheets,Alerts,Popovers, andModality.

Design an information structure that makes it fast and easy to get to content.Organize your information structure in a way that requires a minimum number of taps, swipes, and screens.

设计一个信息架构，使用它很快且容易得到内容。使用一种方式组织你的信息结构，它要求很少的轻敲，滑动和屏幕。

Use touch gestures to create fluidity.Make it easy to move through your interface with minimum friction. For example, you could let people swipe from the side of the screen to return to the previous screen.

使用触摸手势来提高流畅。使用最小的摩擦使得在你的界面移动很容易。例如，你可以让用户通过在屏幕边缘滑动来返回上一级屏幕。

Use standard navigation components.Whenever possible, use standard navigation controls such as page controls, tab bars, segmented controls, table views, collection views, and split views. Users are already familiar with these controls, and will intuitively know how to get around your app.

使用标准导航组件。尽可能，使用标准导航控制，例如页面控制，tab bars，segmented controls, table views, collection views, and split views.用户已经熟悉这些控制，会直观的知道怎么游览你的app。

Use a navigation bar to traverse a hierarchy of data.The navigation bar’s title can show the current position in the hierarchy, and the back button makes it easy to return to the previous location. For specific guidance, seeNavigation Bars.

使用导航来穿越数据的层级。导航栏标题可以显示当前层级的位置，后退键使得回到前一个位置很容易。For specific guidance, seeNavigation Bars.

Use a tab bar to present peer categories of content or functionality.A tab bar lets people quickly and easily switch between categories, regardless of the current location. For specific guidance, seeTab Bars.

使用tab bar展现相同层级的内容或者功能。一个tab bar让用户很快轻易地在类别间切换，不管当前在哪个位置，seeTab Bars.

Use a page control when you have multiple pages of the same type of content.A page control clearly communicates the number of pages available and which one is currently active. The Weather app uses a page control to show location-specific weather pages. For specific guidance, seePage Controls.

当你有很多同样类型内容的页面使用页面控制。页面控制清晰的沟通可用的页面，明确哪一个是当前活跃的页面。天气app使用页面控制来显示基于位置的天气页面。For specific guidance, seePage Controls.

TIP Segmented controls and toolbars don’t enable navigation. Use a segmented control to organize information into different categories. Use a toolbar to provide controls for interacting with the current context. For additional information on these types of elements, seeSegmented ControlsandToolbars.

提示 分段控制和工具条不能使用导航。使用a segmented control来组织信息进入不同的目录。使用工具条来提供与当前环境的交互控制。For additional information on these types of elements, seeSegmented ControlsandToolbars.