It appears that the backForwardList of a WKWebView is readonly, but I've seen people so some pretty magical things to get around this. I need to figure out some way of clearing the history of a WKWebView. Any ideas how I might so this? So far I've tries a few tricks that have failed:
- using keyValue:forKey didn't work.
- using a C pointer
-> didnt work.
I've seen people talk about synthesizing the property and extending the class but I don't really know how that works and couldn't figure it out. Any other ideas?
This code compiles, but I have not tested it...
First I subclass WKWebView to override backForwardList with my own subclass of WKBackForwardList.
Then, in my WKBackForwardList subclass, I can either override backItem & forwardItem to make them return nil, instead of having them look into their respective list (which is most probably the default implementation).
Or I can override backList & forwardList in the same way I did in WKWebView with backForwardList. I do this to add a setter, which will allow me remove items from the lists.
import Foundation import WebKit class WebViewHistory: WKBackForwardList { /* Solution 1: return nil, discarding what is in backList & forwardList */ override var backItem: WKBackForwardListItem? { return nil } override var forwardItem: WKBackForwardListItem? { return nil } /* Solution 2: override backList and forwardList to add a setter */ var myBackList = [WKBackForwardListItem]() override var backList: [WKBackForwardListItem] { get { return myBackList } set(list) { myBackList = list } } func clearBackList() { backList.removeAll() } } class WebView: WKWebView { var history: WebViewHistory override var backForwardList: WebViewHistory { return history } init(frame: CGRect, configuration: WKWebViewConfiguration, history: WebViewHistory) { self.history = history super.init(frame: frame, configuration: configuration) } /* Not sure about the best way to handle this part, it was just required for the code to compile... */ required init?(coder: NSCoder) { if let history = coder.decodeObject(forKey: "history") as? WebViewHistory { self.history = history } else { history = WebViewHistory() } super.init(coder: coder) } override func encode(with aCoder: NSCoder) { super.encode(with: aCoder) aCoder.encode(history, forKey: "history") } }
Worded on iOS8 ~ iOS11.
Objective-C
#pragma clang diagnostic push #pragma clang diagnostic ignored "-Warc-performSelector-leaks" [wek.backForwardList performSelector:NSSelectorFromString(@"_removeAllItems")]; #pragma clang diagnostic pop
Swift 4
webView.backForwardList.perform(Selector(("_removeAllItems")))
!!!!NOTE!!!! THIS METHOD IS DECLARED IN WebKit Open Resource, not a public method。
Reading in the documentation you can get WKBackForwardList for the WKWebView. After that you can find the first item in the backList of WKBackForwardList and after that to use: func go(to: WKBackForwardListItem) -> WKNavigation? And with this you can clean the history up to the first url.
