如何在 WKWebView 中关闭 ipad 的 alertController

Question

我正在使用 WkWebview 加载网站，并且该网站包含一些 javascript 操作。对于 iPhone，它工作正常，因为在用户选择面板中的可用操作之前，confirmPanel 不允许用户触摸面板外部。但是，对于 iPad，它的功能与 iPhone 不同。每当 我尝试触摸警报面板之外，它会崩溃。请查看代码下方的崩溃日志。我尝试使用 UITapGestureRecognizer，但它仍然无法正常工作。

func webView(_ webView: WKWebView, runJavaScriptConfirmPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: @escaping (Bool) -> Void) {

    let alertController = UIAlertController(title: nil, message: message, preferredStyle: .actionSheet)

    alertController.addAction(UIAlertAction(title: "OK", style: .default, handler: { (action) in
        completionHandler(true)
    }))

    alertController.addAction(UIAlertAction(title: "Cancel", style: .default, handler: { (action) in
        completionHandler(false)
    }))

    if UIDevice.current.userInterfaceIdiom != .phone {
        if let popoverController = alertController.popoverPresentationController {
            popoverController.sourceView = self.view
            popoverController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
            popoverController.permittedArrowDirections = []
        }
    }

    self.present(alertController, animated: true, completion: nil)
}

错误信息，

由于未捕获的异常“NSInternalInconsistencyException”而终止应用程序，原因：“未调用传递给 -[webViewios.MainVC webView:runJavaScriptConfirmPanelWithMessage:initiatedByFrame:completionHandler:] 的完成处理程序” *** 首先抛出调用堆栈： (0x21a2f91b 0x211cae17 0x21a2f861 0x287d7293 0x288111b9 0x2886db69 0x21603ac3 0xccd4c 0x8d9e1f 0xcc6d8 0x8d9e1f 0xd1718 0x21603ac3 0x26400cd1 0x263ff26b 0x211e53a9 0x2193ef89 0x219f006f 0x2193f229 0x2193f015 0x22f2fac9 0x26013189 0xd8824 0x215e7873) libc++abi.dylib：以 NSException 类型的未捕获异常终止

Answer 1

在 iPad 中，当您呈现操作表时，取消操作会自动映射到操作表控制面板外的点击。您需要更改 UIAlertController 的 Cancel 按钮的显示方式。

iPad 上没有取消按钮的更新代码

func webView(_ webView: WKWebView, runJavaScriptConfirmPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: @escaping (Bool) -> Void) {

    let alertController = UIAlertController(title: nil, message: message, preferredStyle: .actionSheet)

    alertController.addAction(UIAlertAction(title: "OK", style: .default, handler: { (action) in
        completionHandler(true)
    }))

    alertController.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { (action) in
        completionHandler(false)
    }))

    if UIDevice.current.userInterfaceIdiom != .phone {
        if let popoverController = alertController.popoverPresentationController {
            popoverController.sourceView = self.view
            popoverController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
            popoverController.permittedArrowDirections = []
        }
    }

    self.present(alertController, animated: true, completion: nil)
}

iPad 上带有取消按钮的代码

func webView(_ webView: WKWebView, runJavaScriptConfirmPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: @escaping (Bool) -> Void) {

    let alertController = UIAlertController(title: nil, message: message, preferredStyle: .actionSheet)

    alertController.addAction(UIAlertAction(title: "OK", style: .default, handler: { (action) in
        completionHandler(true)
    }))

    alertController.addAction(UIAlertAction(title: "Cancel", style: .default, handler: { (action) in
        completionHandler(false)
    }))

    if UIDevice.current.userInterfaceIdiom != .phone {
         alertController.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { (action) in
             completionHandler(false)
        }))
        if let popoverController = alertController.popoverPresentationController {
            popoverController.sourceView = self.view
            popoverController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
            popoverController.permittedArrowDirections = []
        }
    }

    self.present(alertController, animated: true, completion: nil)
}

Answer 2

如果UIViewController 和WKWebView 可见，请出示您的UIAlertController。如果不可见，直接执行completionHandler并返回。

func webView(_ webView: WKWebView, runJavaScriptConfirmPanelWithMessage message: String, initiatedByFrame frame: WKFrameInfo, completionHandler: @escaping (Bool) -> Void) {

let alertController = UIAlertController(title: nil, message: message, preferredStyle: .actionSheet)

alertController.addAction(UIAlertAction(title: "OK", style: .default, handler: { (action) in
    completionHandler(true)
}))

alertController.addAction(UIAlertAction(title: "Cancel", style: .default, handler: { (action) in
    completionHandler(false)
}))

if UIDevice.current.userInterfaceIdiom != .phone {
    if let popoverController = alertController.popoverPresentationController {
        popoverController.sourceView = self.view
        popoverController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
        popoverController.permittedArrowDirections = []
    }
}

    if self.viewIfLoaded?.window != nil {
        self.present(alertController, animated: true, completion: nil)
    }
    else {
        completionHandler()
    }
}