BLACK FRIDAY: Save 50% on all my Swift books and bundles! >>

How to control the sites a WKWebView can visit using WKNavigationDelegate

Swift version: 5.10

Paul Hudson    @twostraws   

By default a WKWebView can navigate to any links the user selects, but it’s common to want to restrict that. It only takes three steps to accomplish this:

  1. Make your view controller conform to WKNavigationDelegate.
  2. Assign your view controller to be your web view’s navigationDelegate.
  3. Implement the decidePolicyFor method to decide whether each URL should be allowed or denied.

Let’s try it out now. First, make your view controller conform to WKNavigationDelegate.

Second, set your view controller to be the navigationDelegate property of your web view. This might be done in viewDidLoad(), but you can also change the delegate dynamically. Either way, you need to use this code:

yourWebView.navigationDelegate = self

Finally, implement the decidePolicyFor method. This is the only part that takes any work: you need to pull out the host of the URL that was requested, run any checks you want to make sure it’s OK, then call the decisionHandler() closure with either .allow to allow the URL or .cancel to deny access.

Here’s an example to get you started:

func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
    if let host = navigationAction.request.url?.host {
        if host.contains("hackingwithswift.com") {
            decisionHandler(.allow)
            return
        }
    }

    decisionHandler(.cancel)
}

That code will allow navigation only to URLs that contain “hackingwithswift.com”.

Save 50% in my WWDC sale.

SAVE 50% All our books and bundles are half price for Black Friday, so you can take your Swift knowledge further without spending big! Get the Swift Power Pack to build your iOS career faster, get the Swift Platform Pack to builds apps for macOS, watchOS, and beyond, or get the Swift Plus Pack to learn advanced design patterns, testing skills, and more.

Save 50% on all our books and bundles!

Available from iOS 9.0

Similar solutions…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

BUY OUR BOOKS
Buy Pro Swift Buy Pro SwiftUI Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let us know!

Average rating: 4.1/5

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.