chore: a11y polish (#9259)

apps/toolbox/src/pages/sample-modal.ts

@@ -0,0 +1,23 @@
+import { Page, ShownModallyData, Observable } from '@nativescript/core';
+
+let page: Page;
+let closeCallback: Function;
+export function onShownModally(args: ShownModallyData) {
+	page = <Page>args.object;
+	page.bindingContext = new SampleModal();
+	closeCallback = args.closeCallback;
+
+	if (args.context) {
+		args.context.shownModally = true;
+	}
+}
+
+export class SampleModal extends Observable {
+	close() {
+		// TODO: a11y
+		// if (global.isIOS) {
+		//   (<UIViewController>page.ios).view.accessibilityPerformEscape();
+		// }
+		closeCallback();
+	}
+}