出自UXGuide.net

适当地手势支持

Support Gestures Appropriately

People use their fingers to operate the unique Multi-Touch interface of iPhone OS–based devices, tapping, flicking, and pinching to select, navigate, and read web content and use applications. There are real advantages to using fingers to operate a device: They are always available, they are capable of many different movements, and they give users a sense of immediacy and connection to the device that’s impossible to achieve with an external input device, such as a mouse.

人们使用他们的手指来操作基于 iPhone 操作系统的设备所具有的独特的多点触摸界面，使用点击，滑动，捏的方式去选择，导航，和阅读网页内容与使用应用程序。使用手指操作存在真正的优势：他们支持许多种不同的动作，同时他们给用户一种直观的与设备关联的感觉，而这对于外接输入设备来说不几乎不可能的事不能实现的，如鼠标。

However, fingers have one major disadvantage: They are much bigger than a mouse pointer, regardless of their size, their shape, or the dexterity of their owner. In the context of a display screen, fingers can never be as precise as a mouse pointer.

但是手指有一个主要的缺点，跟鼠标指针相比，无论是在大小，形状还是灵敏度方面都要差得多。在屏幕显示方面，手指永远不可能像鼠标那样精确。

Fortunately, you can meet the challenges of a finger-based input system by having a good user interface design. For the most part, this means making sure your layout accommodates the average size of a fingertip.It also means responding to finger movements with the actions users expect.

幸运的是，一个优秀的用户界面的设计，足以应对以手指为基础的输入系统带来的挑战。在大多数情况下，这意味着你要确保你的布局能容纳一个手指尖的平均大小，同样也意味着用户指尖移动时要获得他们需要的反应。

Users perform specific movements, called gestures, to get particular results. For example, users tap a button to select it and flick or drag to scroll a long list. iPhone users understand these gestures because the built-in applications use them consistently. To benefit from users’ familiarity, therefore, and to avoid confusing them, you should use these gestures appropriately in your application.

用户执行某些具体的移动方式并获得独有的反馈结果，我们称之为手势。例如，用户点击一个按钮去选择它，以及滑动或拖动一个很长的列表。iPhone用户很了解这些手势因为iPhone内置的应用程序一致化的使用了这些手势。因此，得益于用户对这些手势的熟悉，同时为了避免混淆，你应该适当的在你的应用程序中使用这些手势。

The more complex gestures, such as swipe or pinch open, are also used consistently in the built-in applications, but they are less common. In general these gestures are used as shortcuts to expedite a task, not as the only way to perform a task. When viewing a list of messages in Mail, for example, users delete a message by revealing and then tapping the Delete button in the preview row for the message. Users can reveal the Delete button in two different ways:

还有一些更复杂的手势，像横扫或放大，也是一致化的在内置程序中应用，但他们并不常见。一般来说，这些手势被用作快捷方式来加速任务完成，而不是执行任务的方法。例如，当查看邮件列表的时候，用户删除了一条正在显示的邮件，然后点击了预览行的删除按钮。用户可以以两种不同的方式来激活删除按钮：

• Tap the Edit button in the navigation bar, which reveals a delete control in each preview row. Then, tap the delete control in a specific preview row to reveal the Delete button for that message.

点击导航条上的编辑菜单，在每个预览行都会出现一个删除控件。然后在特定的一行点击删除控件就会显示这条信息的删除按钮。

• Make the swipe gesture across a specific preview row to reveal the Delete button for that message.

在特定的预览行使用横扫手势就会显示出这条信息的删除按钮。

The first method takes an extra step, but is easily discoverable because it requires only the tap and begins with the clearly labeled Edit button. The second method is faster, but it requires the user to learn and remember the more specialized swipe gesture.

第一种方式需要额外的步骤，然是很容易被发现。因为它仅仅需要点击已经标识清楚的编辑按钮来开启这一功能。第二种方法更快，但是它要求用户学习并记住更为特殊的滑动手势。

To ensure that your application is discoverable and easy to use, therefore, try to limit the gestures you require to the most familiar, that is, tap and drag. You should also avoid making one of the less common gestures, such as swipe or pinch open, the only way to perform an action. There should always be a simple, straightforward way to perform an action, even if it means an extra tap or two.

为了确保你的应用程序易于使用和发现，所以，试着限制你需要的手势，只保留最熟悉的手势——点击和拖动。你应该避免让像横扫或放大缩小这些不常见的手势成为执行动作的唯一方法。无论在什么情况下（你的应用程序）总是应该有一个简单直接了当的方法去执行一个操作，即使这意味着要多点击一次或者两次。

In most applications, it’s equally important to avoid defining new gestures, especially if these gestures perform actions users already associate with the standard gestures. The primary exception to this recommendation is an immersive application, in which custom gestures can be appropriate. For example, a productivity application that requires users to make a circular gesture to reveal the Delete button in a table row would be confusing and difficult to use. On the other hand, a game might reasonably require users to make a circular gesture to spin a game piece.

在大多数应用程序中，避免定义新的手势同样重要，特别这些新手势执行的操作是用户已经认为它是与标准手势相关联的。但是对于这个建议，最主要的例外是沉浸式应用程序，对它而言，自定义的手势是被认为合适的。例如，一个生产力程序要求用户做出一个圆形的手势来显示一行表格的删除按键是混乱且难以使用的，但是另一方面，对于一个游戏来说要求用户做出一个圆形的手势来转动游戏的一部分就显得比较合理。

Table 3-1 lists the standard gestures users can perform. Be sure to avoid redefining the meaning of these gestures; conversely, if you support these actions in your application, be sure to respond appropriately to the gestures that correspond to them. For more information on how to handle events created by gestures, see iPhone Application Programming Guide.

表3-1列举出了用户可以使用的标准手势。一定要避免重新定义这些手势；如果你在你的应用程序中支持这些操作，一定对这些手势提供适当的响应，且符合与这些操作。想了解更多关于如何创建手势触发事件的内容，请参见“iPhone应用程序编程指南”。

Table 3-1  Gestures users make to interact with iPhone OS–based devices
表3-1 用户可用于与基于iPhone 操作系统的交互的手势

Gesture 手势	Action 操作
Tap 点击	To press or select a control or item (analogous to a single mouse click). 按下或选择一个控件或条目（类似于普通的鼠标点击）
Drag 拖动	To scroll or pan. 滚动或平移
Flick 滑动	To scroll or pan quickly. 快速的滚动或平移
Swipe 横扫	In a table-view row, to reveal the Delete button. 在一个表格视图的行中，显示删除按钮
Double tap 双击	To zoom in and center a block of content or an image. 放大并将内容或图片置于中央 To zoom out (if already zoomed in). 缩小（如果已经放大）
Pinch open (双指捏的手势)放大	To zoom in. 放大
Pinch close (双指捏的手势)缩小	To zoom out. 缩小
Touch and hold 长按	In editable text, to display a magnified view for cursor positioning. 在可编辑文本中，用来显示放大视图中的光标定位