总结UIViewController的view在有navBar和tabBar影响下布局区域的问题

影响 View 布局区域的有以下三个属性:

self.edgesForExtendedLayout (影响View布局区域的主要属性)

self.navigationController.navigationBar.translucent (navigationBar 是否半透明)

self.tabBarController.tabBar.translucent (tabBar 是否半透明)

 

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case 1: edgesForExtendedLayout = UIRectEdgeAll

条件: navigationBar.translucent = YES && tabBar.translucent = YES

结果: View Top == navigationBar Top，View Bottom == tabBar Bottom

 

条件: navigationBar.translucent = NO && tabBar.translucent = YES

结果: View Top == navigationBar Bottom，View Bottom == tabBar Bottom

 

条件: navigationBar.translucent = YES && tabBar.translucent = NO

结果: View Top == navigationBar Top，View Bottom == tabBar Top

 

条件: navigationBar.translucent = NO && tabBar.translucent = NO

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

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case 2: edgesForExtendedLayout = UIRectEdgeTop

条件: navigationBar.translucent = YES && tabBar.translucent = YES

结果: View Top == navigationBar Top，View Bottom == tabBar Top

 

条件: navigationBar.translucent = NO && tabBar.translucent = YES

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

 

条件: navigationBar.translucent = YES && tabBar.translucent = NO

结果: View Top == navigationBar Top，View Bottom == tabBar Top

 

条件: navigationBar.translucent = NO && tabBar.translucent = NO

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

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case 3: edgesForExtendedLayout = UIRectEdgeBottom

条件: navigationBar.translucent = YES && tabBar.translucent = YES

结果: View Top == navigationBar Bottom，View Bottom == tabBar Bottom

 

条件: navigationBar.translucent = NO && tabBar.translucent = YES

结果: View Top == navigationBar Bottom，View Bottom == tabBar Bottom

 

条件: navigationBar.translucent = YES && tabBar.translucent = NO

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

 

条件: navigationBar.translucent = NO && tabBar.translucent = NO

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

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case 4: edgesForExtendedLayout = UIRectEdgeNone

条件: navigationBar.translucent = YES && tabBar.translucent = YES

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

 

条件: navigationBar.translucent = NO && tabBar.translucent = YES

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

 

条件: navigationBar.translucent = YES && tabBar.translucent = NO

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

 

条件: navigationBar.translucent = NO && tabBar.translucent = NO

结果: View Top == navigationBar Bottom，View Bottom == tabBar Top

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iOS 7.0以后

self.navigationController.navigationBar.translucent 和 self.tabBarController.tabBar.translucent 默认值都为 YES.

iOS 6.0以下系统

navigationBar 和 tabBar 默认都是不透明的。

 

edgesForExtendedLayout 的枚举项:

UIRectEdgeNone = 0, navBar 底部与 tabBar 上部之间

UIRectEdgeTop = 1 << 0, navBar 上部与 tabBar 上部之间

UIRectEdgeLeft = 1 << 1,

UIRectEdgeBottom = 1 << 2, navBar 底部与 tabBar 底部之间

UIRectEdgeRight = 1 << 3,

UIRectEdgeAll = UIRectEdgeTop | UIRectEdgeLeft | UIRectEdgeBottom | UIRectEdgeRight

 

下面图中展示了 UIView 的四种情况下的布局区域，绿色为目标 UIView:

View Top == navigationBar Bottom，View Bottom == tabBar Top

 

 

View Top == navigationBar Top，View Bottom == tabBar Bottom

 

 

View Top == navigationBar Bottom，View Bottom == tabBar Bottom

 

 

View Top == navigationBar Top，View Bottom == tabBar Top

 

 

注：

本文是受 http://blog.sina.com.cn/s/blog_1410870560102wu9a.html 启发而写的一篇文章。

本文论证结果是在xcode iOS 12.1 IPhone XR 模拟器上进行的数据校对。