fix(android): don't crash in Fragment.onCreateView on stale-fragment race

NathanWalker · NathanWalker · commit 26d34e136d84 · 2026-06-09T15:07:03.000-07:00
onCreateView already returns null when its entry, resolvedPage, or frame is
missing, but it first called Trace.error, which rethrows through the registered
error handler across the JNI boundary and turns the recoverable case into a
fatal "Calling js method onCreateView failed" crash.

These nulls happen when the FragmentManager drives a stale fragment to
CREATE_VIEW after NativeScript has already torn down the corresponding
backstack entry (process death / activity recreation after rotation or
theme change, clearHistory, or rapid navigate+goBack). The fragment should
just be discarded, not crash the app.

Downgrade the three guards to Trace.messageType.warn so the existing
return-null recovery path is actually reached, consistent with the existing
onDestroy handling of the same race.
diff --git a/packages/core/ui/frame/frame-helper-for-android.ts b/packages/core/ui/frame/frame-helper-for-android.ts
@@ -112,21 +112,33 @@ export class FragmentCallbacksImplementation implements AndroidFragmentCallbacks
 
 		const entry = this.entry;
 		if (!entry) {
-			Trace.error(`${fragment}.onCreateView: entry is null or undefined`);
+			// Recoverable race: a stale fragment is being driven to onCreateView by the
+			// FragmentManager after its entry was cleared.
+			// Using Trace.error (routes to an error handler, which throws) would be fatal as the error handler rethrows across the JNI boundary.
+			if (Trace.isEnabled()) {
+				Trace.write(`${fragment}.onCreateView: entry is null or undefined`, Trace.categories.NativeLifecycle, Trace.messageType.warn);
+			}
 
 			return null;
 		}
 
 		const page = entry.resolvedPage;
 		if (!page) {
-			Trace.error(`${fragment}.onCreateView: entry has no resolvedPage`);
+			// Logging via Trace.error (routes to an error handler, which throws) here is fatal because the registered error handler rethrows across the JNI boundary.
+			if (Trace.isEnabled()) {
+				Trace.write(`${fragment}.onCreateView: entry has no resolvedPage`, Trace.categories.NativeLifecycle, Trace.messageType.warn);
+			}
 
 			return null;
 		}
 
 		const frame = this.frame;
 		if (!frame) {
-			Trace.error(`${fragment}.onCreateView: this.frame is null or undefined`);
+			// Recoverable race: the owning frame was already torn down. Returning null discards
+			// this fragment; using Trace.error (routes to an error handler, which throws) would be fatal as the error handler rethrows across the JNI boundary.
+			if (Trace.isEnabled()) {
+				Trace.write(`${fragment}.onCreateView: this.frame is null or undefined`, Trace.categories.NativeLifecycle, Trace.messageType.warn);
+			}
 
 			return null;
 		}
