Is there a way to set local storage in WKWebView
From @paulvs comment here is what I do.
Set navigation delegate to listen to finished callback.
webView.navigationDelegate = self
Then in the callback, check for value in localStorage and set if needed.
func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
webView.evaluateJavaScript("localStorage.getItem(\"key\")") { (result, error) in
// check if result is what I want
// if it is what I want, do nothing
// if not set it
webView.evaluateJavaScript("localStorage.setItem(\"key\", \"value\")") { (result, error) in
webView.reload()
}
}
}
You do not need to reload the page - just inject the local storage data using WKUserScript
at .atDocumentStart
// Restore local storage
// Instantiate the configuration before instantiating `WKWebView`
let configuration = WKWebViewConfiguration()
// Clear existed local storage just after document element is created
let script = WKUserScript(
source: "window.localStorage.clear();",
injectionTime: .atDocumentStart,
forMainFrameOnly: true
)
configuration.userContentController.addUserScript(script)
// Preare your local storage data
let localStorageData: [AnyHashable : Any] = [:]
if JSONSerialization.isValidJSONObject(localStorageData),
let data = try? JSONSerialization.data(withJSONObject: localStorageData, options: []),
let value = String(data: data, encoding: .utf8) {
// Inject valid local storage data just after document element is created
let script = WKUserScript(
source: "Object.assign(window.localStorage, \(value));",
injectionTime: .atDocumentStart,
forMainFrameOnly: true
)
configuration.userContentController.addUserScript(script)
}
// Instantiate WebView with the configuration
let webView = WKWebView(frame: .zero, configuration: configuration)
// Later you may save the updated local storage
webView.evaluateJavaScript("Object.assign({}, window.localStorage);") { (result, error) in
// let updatedlocalStorageData = (result as? [AnyHashable : Any]) ?? [:]
}