fix: check is disposed fragment is in fragmentMngr

nativescript-core/ui/frame/frame.android.ts

@@ -87,6 +87,16 @@ function getAttachListener(): android.view.View.OnAttachStateChangeListener {
     return attachStateChangeListener;
 }
 
+function nativeArrayIncludes<T>(arr: native.Array<T>, what: T): boolean {
+    for (let i = 0; i < arr.length; i++) {
+        if (arr[i] === what) {
+            return true;
+        }
+    }
+    
+    return false;
+}
+
 export class Frame extends FrameBase {
     public _originalBackground: any;
     private _android: AndroidFrame;
@@ -264,13 +274,28 @@ export class Frame extends FrameBase {
             !this._currentEntry.fragment.isAdded()) {
             return;
         }
+        const fragmentManager: androidx.fragment.app.FragmentManager = this._getFragmentManager();
 
-        const manager: androidx.fragment.app.FragmentManager = this._getFragmentManager();
+        // Check if manager contains the fragment to be removed
-        const transaction = manager.beginTransaction();
+        // This might happen when a dialog is already closed with android back btn
         const fragment = this._currentEntry.fragment;
+        const fragmentFound = nativeArrayIncludes(fragmentManager.getFragments().toArray(), fragment);
+
+        if (traceEnabled()) {
+            const message = fragmentFound ?
+                `Frame.disposeCurrentFragment - fragment(${fragment}) found in fragmentManager(${fragmentManager}). Removing ...` :
+                `Frame.disposeCurrentFragment - fragment(${fragment}) NOT found in fragmentManager(${fragmentManager}). Skipping remove`;
+            traceWrite(message, traceCategories.NativeLifecycle);
+        }
+
+        if (!fragmentFound) {
+            return;
+        }
+
+        const transaction = fragmentManager.beginTransaction();
         const fragmentExitTransition = fragment.getExitTransition();
 
-        // Reset animation to its initial state to prevent mirrorered effect when restore current fragment transitions
+        // Reset animation to its initial state to prevent mirrored effect when restore current fragment transitions
         if (fragmentExitTransition && fragmentExitTransition instanceof org.nativescript.widgets.CustomTransition) {
             fragmentExitTransition.setResetOnTransitionEnd(true);
         }

nativescript-core/utils/utils.ios.ts

@@ -6,8 +6,6 @@ import {
 export { ios };
 export * from "./utils-common";
 
-let mainScreenScale;
-
 export function openFile(filePath: string): boolean {
     try {
         const appPath = ios.getCurrentAppPath();
@@ -47,5 +45,3 @@ export function openUrl(location: string): boolean {
 
     return false;
 }
-
-mainScreenScale = UIScreen.mainScreen.scale;