Thread 1: signal SIGABRT from web view when accessing external link - xcode

Question

I am currently trying to deploy a responsive website on mobile devices (iPhone & iPad) via a WebView.
Here are some details regarding the app :
the application's only purpose is to display the webView containing the website
using the WKWebView component since UIWebView is deprecated in my environment
any external links should load a new page within the webView
currently using Swift 3 and Xcode 9.2
made an Outlet between the WebKit WebView and the ViewController
edited the info.plist ; App Transport Security Setting > set NSAllowArbitraryLoads to true
source code :
ViewController.swift
import UIKit
import WebKit
class ViewController: UIViewController, WKNavigationDelegate {
// edit the url the app should load here
private var domain = "https://example.com/"
#IBOutlet weak var webView: WKWebView!
override func loadView() {
//delegates the navigation of other urls while still inside the webview
let webConfiguration = WKWebViewConfiguration()
webView = WKWebView(frame: .zero, configuration: webConfiguration)
webView.navigationDelegate = self
webView.allowsLinkPreview = false
view = webView
}
override func viewDidLoad() {
super.viewDidLoad()
// calls the website in a 'iframe' style
let url = URL(string: domain)
let request = URLRequest(url: url!)
webView.load(request)
}
func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: #escaping ((WKNavigationActionPolicy) -> Void)) {
// outputs are for debugging purpose
print("webView :\(webView)" + "\n")
print("decidePolicyForNavigationAction :\(navigationAction)" + "\n")
print("decisionHandler :\(decisionHandler)" + "\n")
switch navigationAction.navigationType {
case .linkActivated:
print("request : " + navigationAction.request.url!.absoluteString)
self.webView?.load(navigationAction.request)
return
default:
break
}
if let url = navigationAction.request.url {
print("url : " + url.absoluteString)
}
decisionHandler(.allow)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
AppDelegate.swift :
import UIKit
import WebKit
#UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
return true
}
}
My trouble comes when trying to open external and internal links ; the app will throw a signal SIGABRT.
From what I understand, this error usually happens when there is an Outlet mismatch, but my project has only a single Outlet (WebView / ViewController). I tried deleting it and re-creating it to no avail.
If the issue is that no Outlet are made between the page loaded from an external link and my app I fail to see how to solve this since I have no control over the website.
Note : when I set webView.allowsLinkPreview to true (in func loadView()), the app loads the new page but takes a considerable amount of time. Also the function webView isn't called a second time when this happens.
Any help will be much appreciated.
Thank you.
Edit. as requested in a comment, here is what the debugger throws :
libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)
Also, the Thread 1 SIGABRT signal appears to be in the AppDelegate class.

Answer 1

The interesting error message should be
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Completion handler passed to -[myAppName webView:decidePolicyForNavigationAction:decisionHandler:] was not called'
In webView(_ webView:, decidePolicyFor navigationAction:, decisionHandler:) in one particular case you don't do decisionHandler(someValue), that's why it crashes.
So in
case .linkActivated:
print("request : " + navigationAction.request.url!.absoluteString)
self.webView?.load(navigationAction.request)
return
You need to do decisionHandler(someValue) before you do the return.