Quite often when loading a webpage, XWVObject.denit() crashes my program, on the line webView.evaluateJavaScript(script, completionHandler: nil). This behaviour is inconsistent, so it is difficult to reproduce on demand. I have no experience debugging memory errors, so I don't know exactly what information to provide.
The line on which the program crashes:
Zombies profiling for all instruments:
Zombies profiling for XWebView-related instruments:
Below is the general layout of my code (I have simplified it as much as possible).
This Swift function is called inside the ViewController's loadView():
func setUpWebView(){
let jsContext : JSContext! = JSContext(virtualMachine: jsvm)
jsContext.evaluateScript(myJavaScriptFile)
let fn1 : JSValue! = jsContext.objectForKeyedSubscript("fn1")
let userScript = WKUserScript(
source: "\"use strict\"\n fn1(); \n" + fn1.description,
injectionTime: WKUserScriptInjectionTime.atDocumentEnd,
forMainFrameOnly: true
)
webView = WKWebView(frame: self.view.frame, configuration: WKWebViewConfiguration())
webView!.configuration.userContentController.addUserScript(userScript)
webView!.loadPlugin(Tokenizing(), namespace: "Tokenizing")
webView!.navigationDelegate = self
}
This Swift class is loaded into the webView as a plugin:
class Tokenizing: NSObject {
@objc func tokenize(_ callback: XWVScriptObject, _ input: String) {
let inputText: NSString = input as NSString
var tokens = [String]()
// ...
// Do tokenising here, and add to tokens array.
// ...
callback.call(arguments: [tokens], completionHandler: nil)
}
init() { }
}
This JavaScript function is added to webView.configuration.userContentController as a WKUserScript:
function fn1(){
/* The callback that Swift's Tokenizing.tokenize calls. */
function callback(tokens){
var div = document.createElement('div');
tokens.forEach(function(token) {
var span = document.createElement('span');
span.innerText = token;
div.appendChild(span);
});
document.body.appendChild(div);
}
// We call the Swift function many times quickly.
for(var i = 0; i < 500; i++) window.Tokenizing.tokenize(callback, ["some mock text to tokenize"]);
}
Edit: added mocked text data for JS function.
Quite often when loading a webpage,
XWVObject.denit()crashes my program, on the linewebView.evaluateJavaScript(script, completionHandler: nil). This behaviour is inconsistent, so it is difficult to reproduce on demand. I have no experience debugging memory errors, so I don't know exactly what information to provide.The line on which the program crashes:
Zombies profiling for all instruments:
Zombies profiling for XWebView-related instruments:
Below is the general layout of my code (I have simplified it as much as possible).
This Swift function is called inside the
ViewController'sloadView():This Swift class is loaded into the
webViewas a plugin:This JavaScript function is added to
webView.configuration.userContentControlleras aWKUserScript:Edit: added mocked text data for JS function.