fix(ios): navigatingTo event handling (#10120)

packages/core/ui/frame/index.ios.ts

@@ -307,7 +307,16 @@ export class Frame extends FrameBase {
 	}
 
 	public _onNavigatingTo(backstackEntry: BackstackEntry, isBack: boolean) {
-		super._onNavigatingTo(backstackEntry, isBack);
+		// for now to not break iOS events chain (calling navigation events from controller delegates)
+		// we dont call super(which would also trigger events) but only notify the frame of the navigation
+		// though it means events are not triggered at the same time (lifecycle) on iOS / Android
+		this.notify({
+			eventName: Page.navigatingToEvent,
+			object: this,
+			isBack,
+			entry: backstackEntry,
+			fromEntry: this._currentEntry,
+		});
 	}
 }
 

packages/core/ui/page/index.ios.ts

@@ -118,7 +118,14 @@ class UIViewControllerImpl extends UIViewController {
 		}
 
 		const frame = this.navigationController ? (<any>this.navigationController).owner : null;
+		const newEntry = this[ENTRY];
 
+		// Don't raise event if currentPage was showing modal page.
+		if (!owner._presentedViewController && newEntry && (!frame || frame.currentPage !== owner)) {
+			const isBack = isBackNavigationTo(owner, newEntry);
+			owner.onNavigatingTo(newEntry.entry.context, isBack, newEntry.entry.bindingContext);
+		}
+		
 		if (frame) {
 			if (!owner.parent) {
 				owner._frame = frame;