Undo and Redo
The user initiates a undo operation by shaking the device, which displays a warning box to let them:
- Undo what they just typed.
- Re-enter previously unfinished input
- Cancel undo Operation
You can support undo actions in your app in a more general way, by stating:
- Actions that users can undo or redo
- In which case your app should think of a rocking event as a undo gesture
- What level of revocation is supported
View Undo architecture to learn how to implement this behavior in your code. If your app supports Undo and redo, follow the guidelines below to provide a good user experience.
provide a short description of the phrase to tell the user exactly what they are undoing or re-doing. iOS automatically provides a "undo" and "redo" phrase for the button title of the Undo warning box (including a space after the phrase), but you need to provide one or two words to describe the actions that the user can undo or redo. For example, you might provide the word "name" or "Address change" to create a button title like "Undo name" or "Redo address change". (Note that the Cancel button of the warning box can not be changed or removed.) ）
do not provide text that is too long. Button titles that are too long are truncated and can be difficult for users to identify. And because this is a button title, use the title style capitalization and do not add punctuation.
do not overload the shake gesture. Even if you can programmatically set when a shake event is treated as a undo operation, if they are simultaneously using a shake to perform a different action, the user will be confused. Analyze the user interaction in your app without causing users to not understand the results of the shake gesture.
use the system-provided undo and redo buttons only when undoing and re-doing are features of your app. Remember that shaking gestures are the primary way for users to request undo and redo, and it becomes confusing to provide two different ways to perform the same task. If you think it is important to provide clear, dedicated undo and redo controls, you can place the system-provided buttons in the navigation bar. (View toolbar and Navigation Bar buttons Learn more about these buttons.) ）
clearly link the undo and redo functionality to the user's current environment, not the previous environment. Consider the circumstances in which you allow revocation and re-doing. In general, users expect their changes and actions to take effect immediately.
This article is translated from the official Apple development document to view the integration set: Https://github.com/Cloudox/iOS-Human-Interface-Guidelines All rights reserved: Http://blog.csdn.net/cloudox_
"IOS Human Interface Guidelines"--undo and Redo
