定制UINavigationBar的:pushItem不会被调用以前的iOS
问题描述:
我做UINavigationBar的一个子类覆盖:定制UINavigationBar的:pushItem不会被调用以前的iOS
func pushItem(_ item: UINavigationItem, animated: Bool) {
当我把我的第一次的viewController我navigationController功能获取的正确呼吁iOS11。 但是它在iOS10及更低版本上根本没有被调用。
有什么在iOS11中以pushItem
get的方式进行了更改?
感谢您的帮助
答
这似乎是一个已知的issue。
要解决这个问题,我最终实现了自定义的NavigationController,以便与NavigationBar配对使用。只要我可以看到只有pushViewController和popToRootViewController不按预期工作。所以,下面的代码覆盖了所有的导航的情况下适用于iOS 10.
NavigationBar.swift:
final class NavigationBar: UINavigationBar {
override func pushItem(_ item: UINavigationItem, animated: Bool) {
return transit(to: item, isNewItem: true, animated: animated) {
super.pushItem(item, animated: animated)
}
}
override func popItem(animated: Bool) -> UINavigationItem? {
return transit(to: backItem, isNewItem: false, animated: animated) {
super.popItem(animated: animated)
}
}
override func setItems(_ items: [UINavigationItem]?, animated: Bool) {
let isNewItem = items?.last
.flatMap {self.items?.contains($0)}
.map {!$0}
?? true
return transit(to: items?.last, isNewItem: isNewItem, animated: animated) {
super.setItems(items, animated: animated)
}
}
func transit<T>(to item: UINavigationItem?, isNewItem: Bool, animated: Bool, action:() -> T) -> T {
CATransaction.begin(); defer {CATransaction.commit()}
CATransaction.setDisableActions(!animated)
doSomeCoolAnimatedStuff(isNewItem)
return action()
}
}
NavigationController.swift:
final class NavigationController: UINavigationController {
private var baforeIos11: Bool {if #available(iOS 11.0, *) {return false} else {return true}}
override func pushViewController(_ viewController: UIViewController, animated: Bool) {
guard let bar = navigationBar as? NavigationBar, baforeIos11 else {
return super.pushViewController(viewController, animated: animated)
}
return bar.transit(to: viewController.navigationItem, isNewItem: true, animated: true) {
super.pushViewController(viewController, animated: animated)
}
}
override func popToRootViewController(animated: Bool) -> [UIViewController]? {
guard let bar = navigationBar as? NavigationBar else {
return super.popToRootViewController(animated: animated)
}
return bar.transit(to: viewControllers.first?.navigationItem, isNewItem: false, animated: true) {
super.popToRootViewController(animated: animated)
}
}
}
我也试着设置导航栏授人以自我但它打破导航过程导致视图控制器不被弹出。