From 0e34a27d2481b96d28eec112bd876dd4d9f8ece5 Mon Sep 17 00:00:00 2001
From: Marcus Hellberg <marcus@vaadin.com>
Date: Thu, 7 Mar 2024 14:07:25 -0800
Subject: [PATCH] Complete push example

---
 .../com/baeldung/introduction/PushView.java   | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/vaadin/src/main/java/com/baeldung/introduction/PushView.java b/vaadin/src/main/java/com/baeldung/introduction/PushView.java
index 28d8162003..b49aa06e4d 100644
--- a/vaadin/src/main/java/com/baeldung/introduction/PushView.java
+++ b/vaadin/src/main/java/com/baeldung/introduction/PushView.java
@@ -1,6 +1,5 @@
 package com.baeldung.introduction;
 
-import com.vaadin.flow.component.html.H1;
 import com.vaadin.flow.component.html.Span;
 import com.vaadin.flow.component.orderedlayout.VerticalLayout;
 import com.vaadin.flow.router.Route;
@@ -16,12 +15,18 @@ public class PushView extends VerticalLayout {
     public PushView() {
         var output = new Span();
 
-        add(new H1("Server Push"), output);
+        // Publish server time once a second
+        var serverTime = Flux.interval(Duration.ofSeconds(1))
+                .map(o -> "Server time: " + Instant.now());
 
-        Flux.interval(Duration.ofSeconds(1))
-                .map(o -> "Server time: " + Instant.now())
-                .subscribe(time -> getUI().ifPresent(ui -> ui.access(() -> {
-                    output.setText(time);
-                })));
+
+        serverTime.subscribe(time ->
+                // ui.access is required to update the UI from a background thread
+                getUI().ifPresent(ui ->
+                        ui.access(() -> output.setText(time))
+                )
+        );
+
+        add(output);
     }
 }