fix(android): IllegalStateException with tabview&nested frames (#6495)

tns-core-modules/ui/frame/frame.android.ts

@@ -859,7 +859,38 @@ class FragmentCallbacksImplementation implements AndroidFragmentCallbacks {
         if (traceEnabled()) {
             traceWrite(`${fragment}.onDestroy()`, traceCategories.NativeLifecycle);
         }
+
         superFunc.call(fragment);
+
+        const entry = this.entry;
+        if (!entry) {
+            traceError(`${fragment}.onDestroy: entry is null or undefined`);
+            return null;
+        }
+
+        const page = entry.resolvedPage;
+        if (!page) {
+            traceError(`${fragment}.onDestroy: entry has no resolvedPage`);
+            return null;
+        }
+
+        // fixes 'java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first'.	
+        // on app resume in nested frame scenarios with support library version greater than 26.0.0
+        // HACK: this whole code block shouldn't be necessary as the native view is supposedly removed from its parent 
+        // right after onDestroyView(...) is called but for some reason the fragment view (page) still thinks it has a 
+        // parent while its supposed parent believes it properly removed its children; in order to "force" the child to 
+        // lose its parent we temporarily add it to the parent, and then remove it (addViewInLayout doesn't trigger layout pass)
+        const nativeView = page.nativeViewProtected;
+        if (nativeView != null) {	
+            const parentView = nativeView.getParent();	
+            if (parentView instanceof android.view.ViewGroup) {
+                if (parentView.getChildCount() === 0) {
+                    parentView.addViewInLayout(nativeView, -1, new org.nativescript.widgets.CommonLayoutParams());
+                }
+
+                parentView.removeView(nativeView);	
+            }
+        }
     }
 
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