ios - 强制应用程序在进入后台时始终采用相同的形式

Question

我正在开发一个具有多种形式的应用程序，用户可能处于这些形式中的任何一种，并决定将应用程序转到后台。如何强制应用程序在进入后台时始终保持相同的形式？

为了避免疑义，我试着用例子来更好地解释:我的应用程序中有 45 个 View 。用户可以在 View 1、2、3、4 上......但是当他将应用程序置于后台时，我想立即转到 View 9。谢谢。

Answer 1

您应该实现 State Preservation and Restoration在您的应用中。

The state preservation system in UIKit provides a simple but flexible infrastructure for preserving and restoring the state of your app’s view controllers and views.

The job of the infrastructure is to drive the preservation and restoration processes at the appropriate times. To do that, UIKit needs help from your app. Only you understand the content of your app, and so only you can write the code needed to save and restore that content.

And when you update your app’s UI, only you know how to map older preserved content to the newer objects in your interface.

您必须在三个地方考虑​​应用中的状态保存:

• 您的应用委托(delegate)对象，它管理应用的顶级状态
• 您应用的 View Controller 对象，用于管理应用用户界面的整体状态
• 您应用的自定义 View ，其中可能包含一些需要保留的自定义数据

调查:

• > iOS App Programming Guide - State Preservation and Restoration
• > UIViewControllerRestoration Protocol Reference
• > An iOS 7 State Preservation and Restoration Tutorial