自己管理searchBar的frame,解决Ipad上的searchBar不能显示cancel按钮.
self.navigationItem.titleView = self.searchBar
Discussion
Cancel buttons are not displayed for apps running on iPad, even when you specify YES for the showsCancelButton parameter
用xib会有问题，在storyBoard创建一个UINavigationController，创建一个带searchBar的viewContorller用storyBoard去初始化界面，并且把searchBar拖到storyBoard上，设置显示cancel按钮。设置UINavigationController的根控制器为viewContorller。不过注意次方案是并没有把searchBar放在self.navigationItem.titleView上，而是放在self.navigationController?.navigationBar下面.所以在你push方式到该界面时会显示44.0左右的navigationBar高度在searchBar上面。所以需要我们手动隐藏navigationBar:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.navigationController?.setNavigationBarHidden(true, animated: false)
}
//iOS10及以下以这种方式添加的searchBar层级会在比较里面被遮挡，需要手动改变层级到最上层
if #available(iOS 10.0, *) {
self.view.bringSubview(toFront: self.searchBar)
}
//跳转到改viewCintroller需要自带一个navigationControlle
let storyboard: UIStoryboard = UIStoryboard(name: "控制器所在stiryboard名字", bundle: nil)
if let searchNavigationController = storyboard.instantiateViewController(withIdentifier: "自带导航控制器的storyboardId") as? UIPopGestureNavigationController {
if let viewController = searchNavigationController.viewControllers.first as? SearchExistingCloudContactsViewController {
viewController.phoneNumber = phoneNumber
}
self.present(searchNavigationController, animated: true, completion: nil)
}
这种方案是自己手动添加到navigationBar，并且使用frame布局，需要自己手动更新横竖屏时的searchBar的frame.手动添加一个rightBarItem和leftBarItem,searchBar的长度为navigationBar的width减掉rightBarItem和leftBarItem的width(可以根据实际设置间距):
//初始化
if UIDevice.current.userInterfaceIdiom == .pad {
let cancelButtonItem = UIBarButtonItem(customView: self.cancelButton)
self.cancelButton.addTarget(self, action: #selector(cancelAction), for: .touchUpInside)
self.navigationItem.rightBarButtonItem = cancelButtonItem
let backlButtonItem = UIBarButtonItem(customView: self.backButton)
self.backButton.addTarget(self, action: #selector(backAction), for: .touchUpInside)
self.navigationItem.leftBarButtonItem = backlButtonItem
if let navigationBarButtonFrame = self.navigationController?.navigationBar.frame {
self.searchBar.frame = CGRect(x: self.backButton.frame.size.width + 30.0, y: (navigationBarButtonFrame.size.height - self.cancelButton.frame.size.height) / 2.0, width: navigationBarButtonFrame.size.width - self.cancelButton.frame.size.width - self.backButton.frame.size.width - 60.0, height: self.cancelButton.frame.size.height)
self.navigationItem.titleView = self.searchBar
}
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
if let navigationBarButtonFrame = self.navigationController?.navigationBar.frame {
self.searchBar.frame = CGRect(x: self.backButton.frame.size.width + 30.0, y: (navigationBarButtonFrame.size.height - self.cancelButton.frame.size.height) / 2.0, width: navigationBarButtonFrame.size.width - self.cancelButton.frame.size.width - self.backButton.frame.size.width - 60.0, height: self.cancelButton.frame.size.height)
}
}