UIBarButtonItem

Question

如何在左上角的UIBarButtonItem下创建背景：

Answer 1

您应该告诉设计师创建该类型的按钮图像。

Answer 2

UINavigationBar.appearance().layer.shadowColor = UIColor.blackColor().CGColor
UINavigationBar.appearance().layer.shadowOffset = CGSizeMake(1, 1)
UINavigationBar.appearance().layer.shadowRadius = 3
UINavigationBar.appearance().layer.shadowOpacity = 1