Merge pull request #401 from rencsikmarian/fix-double-webview-init-retain-cycles-400

fix: resolve double WebView initialization and script handler retain cycles (#400)

Author: riderx

ios/Sources/InAppBrowserPlugin/WKWebViewController.swift

@@ -86,7 +86,7 @@ open class WKWebViewController: UIViewController, WKScriptMessageHandler {
         self.setPreventDeeplink(preventDeeplink: preventDeeplink)
         self.initWebview(isInspectable: isInspectable)
     }
-
+    
     public init(url: URL, headers: [String: String], isInspectable: Bool, credentials: WKWebViewCredentials? = nil, preventDeeplink: Bool, blankNavigationTab: Bool, enabledSafeBottomMargin: Bool, blockedHosts: [String]) {
         super.init(nibName: nil, bundle: nil)
         self.blankNavigationTab = blankNavigationTab
@@ -153,6 +153,8 @@ open class WKWebViewController: UIViewController, WKScriptMessageHandler {
 
     internal var preShowSemaphore: DispatchSemaphore?
     internal var preShowError: String?
+    private var isWebViewInitialized = false
+    
 
     func setHeaders(headers: [String: String]) {
         self.headers = headers
@@ -169,7 +171,7 @@ open class WKWebViewController: UIViewController, WKScriptMessageHandler {
     func setPreventDeeplink(preventDeeplink: Bool) {
         self.preventDeeplink = preventDeeplink
     }
-
+    
     func setBlockedHosts(blockedHosts: [String]) {
         self.blockedHosts = blockedHosts
     }
@@ -393,6 +395,10 @@ open class WKWebViewController: UIViewController, WKScriptMessageHandler {
 
     override open func viewDidDisappear(_ animated: Bool) {
         super.viewDidDisappear(animated)
+      
+        if self.isBeingDismissed || self.isMovingFromParent {
+              self.cleanupWebView()
+        }
 
         if let capacitorStatusBar = capacitorStatusBar {
             self.capBrowserPlugin?.bridge?.webView?.superview?.addSubview(capacitorStatusBar)
@@ -582,18 +588,24 @@ open class WKWebViewController: UIViewController, WKScriptMessageHandler {
     }
 
     open func initWebview(isInspectable: Bool = true) {
+        if self.isWebViewInitialized {
+            return
+        }
+        self.isWebViewInitialized = true
         self.view.backgroundColor = UIColor.white
 
         self.extendedLayoutIncludesOpaqueBars = true
         self.edgesForExtendedLayout = [.bottom]
 
         let webConfiguration = WKWebViewConfiguration()
         let userContentController = WKUserContentController()
-        userContentController.add(self, name: "messageHandler")
-        userContentController.add(self, name: "preShowScriptError")
-        userContentController.add(self, name: "preShowScriptSuccess")
-        userContentController.add(self, name: "close")
-        userContentController.add(self, name: "magicPrint")
+
+        let weakHandler = WeakScriptMessageHandler(self)
+        userContentController.add(weakHandler, name: "messageHandler")
+        userContentController.add(weakHandler, name: "preShowScriptError")
+        userContentController.add(weakHandler, name: "preShowScriptSuccess")
+        userContentController.add(weakHandler, name: "close")
+        userContentController.add(weakHandler, name: "magicPrint")
 
         // Inject JavaScript to override window.print
         let script = WKUserScript(
@@ -1980,3 +1992,16 @@ class PassThroughView: UIView {
 extension WKNavigationActionPolicy {
     static let preventDeeplinkActionPolicy = WKNavigationActionPolicy(rawValue: WKNavigationActionPolicy.allow.rawValue + 2)!
 }
+
+class WeakScriptMessageHandler: NSObject, WKScriptMessageHandler {
+    weak var delegate: WKScriptMessageHandler?
+    
+    init(_ delegate: WKScriptMessageHandler) {
+        self.delegate = delegate
+        super.init()
+    }
+    
+    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
+        self.delegate?.userContentController(userContentController, didReceive: message)
+    }
+}