在iOS 13中,模态视图控制器在呈现时有一个新的行为。
现在它不是全屏默认情况下,当我向下滑动时,应用会自动解除视图控制器。
我怎么能防止这种行为,并回到旧的全屏模态vc?
谢谢
在iOS 13中,模态视图控制器在呈现时有一个新的行为。
现在它不是全屏默认情况下,当我向下滑动时,应用会自动解除视图控制器。
我怎么能防止这种行为,并回到旧的全屏模态vc?
谢谢
当前回答
有多种方法可以做到这一点,我认为每一种方法都适合一个项目,但不适合另一个项目,所以我想我将它们保留在这里,也许其他人会处理不同的情况。
1-覆盖当前
如果你有一个BaseViewController,你可以重写present(_ viewcontrollertoppresent: animated flag: completion:)方法。
class BaseViewController: UIViewController {
// ....
override func present(_ viewControllerToPresent: UIViewController,
animated flag: Bool,
completion: (() -> Void)? = nil) {
viewControllerToPresent.modalPresentationStyle = .fullScreen
super.present(viewControllerToPresent, animated: flag, completion: completion)
}
// ....
}
使用这种方法,您不需要对任何present调用做任何更改,因为我们只是覆盖了present方法。
2-扩展:
extension UIViewController {
func presentInFullScreen(_ viewController: UIViewController,
animated: Bool,
completion: (() -> Void)? = nil) {
viewController.modalPresentationStyle = .fullScreen
present(viewController, animated: animated, completion: completion)
}
}
用法:
presentInFullScreen(viewController, animated: true)
3-对于一个UIViewController
let viewController = UIViewController()
viewController.modalPresentationStyle = .fullScreen
present(viewController, animated: true, completion: nil)
4-从故事板
选择一个segue并将演示设置为FullScreen。
5 -狂饮
extension UIViewController {
static func swizzlePresent() {
let orginalSelector = #selector(present(_: animated: completion:))
let swizzledSelector = #selector(swizzledPresent)
guard let orginalMethod = class_getInstanceMethod(self, orginalSelector), let swizzledMethod = class_getInstanceMethod(self, swizzledSelector) else{return}
let didAddMethod = class_addMethod(self,
orginalSelector,
method_getImplementation(swizzledMethod),
method_getTypeEncoding(swizzledMethod))
if didAddMethod {
class_replaceMethod(self,
swizzledSelector,
method_getImplementation(orginalMethod),
method_getTypeEncoding(orginalMethod))
} else {
method_exchangeImplementations(orginalMethod, swizzledMethod)
}
}
@objc
private func swizzledPresent(_ viewControllerToPresent: UIViewController,
animated flag: Bool,
completion: (() -> Void)? = nil) {
if #available(iOS 13.0, *) {
if viewControllerToPresent.modalPresentationStyle == .automatic {
viewControllerToPresent.modalPresentationStyle = .fullScreen
}
}
swizzledPresent(viewControllerToPresent, animated: flag, completion: completion)
}
}
用法: 在你的AppDelegate内部应用(_ application: didFinishLaunchingWithOptions)中添加这一行:
UIViewController.swizzlePresent()
使用这种方式,您不需要对任何present调用做任何更改,因为我们正在运行时替换present方法实现。 如果你想知道什么是swizzling,你可以查看这个链接: https://nshipster.com/swift-objc-runtime/
其他回答
override modalPresentationStyle将修复使用或不使用编码器创建的UIViewControllers的样式。
优点:
你放置它的唯一位置。 不需要知道应该设置哪个init或awake方法
劣势:
你不能从外部改变它,像接口构建器或配置从代码
解决方案:
override var modalPresentationStyle: UIModalPresentationStyle {
get { .fullScreen }
set { }
}
最新版本为iOS 13和Swift 5.x
let vc = ViewController(nibName: "ViewController", bundle: nil)
vc。modalPresentationStyle = .fullScreen
self.present(vc, animated: true, completion: nil)
我通过使用方法swizzling(Swift 4.2)实现了它:
创建UIViewController扩展,如下所示
extension UIViewController {
@objc private func swizzled_presentstyle(_ viewControllerToPresent: UIViewController, animated: Bool, completion: (() -> Void)?) {
if #available(iOS 13.0, *) {
if viewControllerToPresent.modalPresentationStyle == .automatic || viewControllerToPresent.modalPresentationStyle == .pageSheet {
viewControllerToPresent.modalPresentationStyle = .fullScreen
}
}
self.swizzled_presentstyle(viewControllerToPresent, animated: animated, completion: completion)
}
static func setPresentationStyle_fullScreen() {
let instance: UIViewController = UIViewController()
let aClass: AnyClass! = object_getClass(instance)
let originalSelector = #selector(UIViewController.present(_:animated:completion:))
let swizzledSelector = #selector(UIViewController.swizzled_presentstyle(_:animated:completion:))
let originalMethod = class_getInstanceMethod(aClass, originalSelector)
let swizzledMethod = class_getInstanceMethod(aClass, swizzledSelector)
if let originalMethod = originalMethod, let swizzledMethod = swizzledMethod {
method_exchangeImplementations(originalMethod, swizzledMethod)
}
}
}
在AppDelegate中,在application:didFinishLaunchingWithOptions中:调用swizzling代码通过调用:
UIViewController.setPresentationStyle_fullScreen()
class MyViewController: UIViewController {
convenience init() {
self.init(nibName:nil, bundle:nil)
self.modalPresentationStyle = .fullScreen
}
override func viewDidLoad() {
super.viewDidLoad()
}
}
而不是调用self。modalPresentationStyle = . fullscreen对于每个视图控制器,你可以子类化UIViewController并在任何地方使用MyViewController。
为UIViewController创建一个类别(比如UIViewController+PresentationStyle)。向其添加以下代码。
-(UIModalPresentationStyle)modalPresentationStyle{
return UIModalPresentationStyleFullScreen;
}