feat: add API for setting assertive to Notification

vaadin-notification-flow-parent/vaadin-notification-flow/src/main/java/com/vaadin/flow/component/notification/Notification.java

@@ -198,6 +198,31 @@ public Notification(String text, int duration, Position position) {
         setPosition(position);
     }
 
+    /**
+     * Creates a Notification with given text String, duration, position and
+     * assertive state.
+     * <P>
+     * Set to {@code 0} or a negative number to disable the notification
+     * auto-closing.
+     *
+     * @param text
+     *            the text of the notification
+     * @param duration
+     *            the duration in milliseconds to show the notification
+     * @param position
+     *            the position of the notification. Valid enumerate values are
+     *            TOP_STRETCH, TOP_START, TOP_CENTER, TOP_END, MIDDLE,
+     *            BOTTOM_START, BOTTOM_CENTER, BOTTOM_END, BOTTOM_STRETCH
+     * @param assertive
+     *            whether the notification should have {@code aria-live}
+     *            attribute set to {@code assertive} or {@code polite}
+     */
+    public Notification(String text, int duration, Position position,
+            boolean assertive) {
+        this(text, duration, position);
+        setAssertive(assertive);
+    }
+
     /**
      * Creates a notification with given components inside.
      * <p>
@@ -232,6 +257,31 @@ private void removeAutoAdded() {
         }
     }
 
+    /**
+     * Shows a notification in the current page with given text, duration,
+     * position and assertive state.
+     *
+     * @param text
+     *            the text of the Notification
+     * @param duration
+     *            the duration in milliseconds to show the notification
+     * @param position
+     *            the position of the notification. Valid enumerate values are
+     *            TOP_STRETCH, TOP_START, TOP_CENTER, TOP_END, MIDDLE,
+     *            BOTTOM_START, BOTTOM_CENTER, BOTTOM_END, BOTTOM_STRETCH
+     * @param assertive
+     *            whether the notification should have {@code aria-live}
+     *            attribute set to {@code assertive} or {@code polite}
+     * @return the notification
+     */
+    public static Notification show(String text, int duration,
+            Position position, boolean assertive) {
+        Notification notification = new Notification(text, duration, position,
+                assertive);
+        notification.open();
+        return notification;
+    }
+
     /**
      * Shows a notification in the current page with given text, duration and
      * position.
@@ -248,9 +298,7 @@ private void removeAutoAdded() {
      */
     public static Notification show(String text, int duration,
             Position position) {
-        Notification notification = new Notification(text, duration, position);
-        notification.open();
-        return notification;
+        return show(text, duration, position, false);
     }
 
     /**
@@ -501,6 +549,29 @@ public int getDuration() {
         return getElement().getProperty("duration", 0);
     }
 
+    /**
+     * When true, the notification card has {@code aria-live} attribute set to
+     * {@code assertive} instead of {@code polite}. This makes screen readers
+     * announce the notification content immediately when it appears.
+     *
+     * @param assertive
+     *            the value to set
+     */
+    public void setAssertive(boolean assertive) {
+        getElement().setProperty("assertive", assertive);
+    }
+
+    /**
+     * When true, the notification card has {@code aria-live} attribute set to
+     * {@code assertive} instead of {@code polite}. This makes screen readers
+     * announce the notification content immediately when it appears.
+     *
+     * @return the {@code assertive} property from the webcomponent
+     */
+    public boolean isAssertive() {
+        return getElement().getProperty("assertive", false);
+    }
+
     /**
      * {@inheritDoc}
      * <p>

vaadin-notification-flow-parent/vaadin-notification-flow/src/test/java/com/vaadin/flow/component/notification/NotificationTest.java

@@ -367,4 +367,18 @@ public void setText_notificationHasUnmodifiedText() {
         Assert.assertEquals("foo > bar",
                 notification.getElement().getProperty("text"));
     }
+
+    @Test
+    public void setAssertive_isAssertive() {
+        Notification notification = new Notification();
+        notification.setAssertive(true);
+        Assert.assertEquals(notification.isAssertive(), true);
+        Assert.assertTrue(
+                notification.getElement().getProperty("assertive", false));
+
+        notification.setAssertive(false);
+        Assert.assertEquals(notification.isAssertive(), false);
+        Assert.assertFalse(
+                notification.getElement().getProperty("assertive", false));
+    }
 }

vaadin-notification-flow-parent/vaadin-notification-flow/src/test/java/com/vaadin/flow/component/notification/tests/NotificationTest.java

@@ -59,6 +59,15 @@ public void stringDurAndPositionCtor() {
                 notification.getPosition().getClientName());
     }
 
+    @Test
+    public void stringDurationPositionAndAssertiveCtor() {
+        notification = new Notification("fooo", 10000, Position.TOP_END, true);
+        Assert.assertEquals(10000, notification.getDuration(), 0);
+        Assert.assertEquals("top-end",
+                notification.getPosition().getClientName());
+        Assert.assertTrue(notification.isAssertive());
+    }
+
     @Test
     public void componentCtor() {
         notification = new Notification(new Label(), new NativeButton());
@@ -70,10 +79,11 @@ public void componentCtor() {
 
     @Test
     public void staticCtor() {
-        notification = Notification.show("fooooo", 4000,
-                Position.BOTTOM_CENTER);
+        notification = Notification.show("fooooo", 4000, Position.BOTTOM_CENTER,
+                true);
         Assert.assertEquals("bottom-center",
                 notification.getPosition().getClientName());
+        Assert.assertTrue(notification.isAssertive());
     }
 
     @Test