fix #2025

Author: pichillilorenzo

flutter_inappwebview/CHANGELOG.md

@@ -15,6 +15,7 @@
 - Added `InAppWebViewController.enableSlowWholeDocumentDraw` static method
 - Added `CookieManager.flush` method
 - Updated `InAppWebViewController.takeScreenshot` implementation to support screenshot out of visible viewport when `InAppWebViewController.enableSlowWholeDocumentDraw` is called
+- Fixed "After dispose a InAppWebViewKeepAlive using InAppWebViewController.disposeKeepAlive. NullPointerException is thrown when main activity enter destroyed state." [#2025](https://github.com/pichillilorenzo/flutter_inappwebview/issues/2025)
 
 #### macOS and iOS Platforms
 - Moved `WKUserContentController` initialization on `preWKWebViewConfiguration` to fix possible `undefined is not an object (evaluating 'window.webkit.messageHandlers')` javascript error

flutter_inappwebview_android/CHANGELOG.md

@@ -4,6 +4,7 @@
 - Added `InAppWebViewController.enableSlowWholeDocumentDraw` static method
 - Added `CookieManager.flush` method
 - Updated `InAppWebViewController.takeScreenshot` implementation to support screenshot out of visible viewport when `InAppWebViewController.enableSlowWholeDocumentDraw` is called
+- Fixed "After dispose a InAppWebViewKeepAlive using InAppWebViewController.disposeKeepAlive. NullPointerException is thrown when main activity enter destroyed state." [#2025](https://github.com/pichillilorenzo/flutter_inappwebview/issues/2025)
 
 ## 1.1.3
 

flutter_inappwebview_android/android/src/main/java/com/pichillilorenzo/flutter_inappwebview_android/webview/InAppWebViewManager.java

@@ -215,9 +215,11 @@ public void dispose() {
     super.dispose();
     Collection<FlutterWebView> flutterWebViews = keepAliveWebViews.values();
     for (FlutterWebView flutterWebView : flutterWebViews) {
-      String keepAliveId = flutterWebView.keepAliveId;
-      if (keepAliveId != null) {
-        disposeKeepAlive(flutterWebView.keepAliveId);
+      if (flutterWebView != null) {
+        String keepAliveId = flutterWebView.keepAliveId;
+        if (keepAliveId != null) {
+          disposeKeepAlive(keepAliveId);
+        }
       }
     }
     keepAliveWebViews.clear();