feat: add position value to SlideChangeEvent

Close #10

Author: paodb

src/main/java/com/flowingcode/vaadin/addons/carousel/Carousel.java

@@ -23,6 +23,7 @@
 import com.vaadin.flow.component.ComponentEvent;
 import com.vaadin.flow.component.ComponentEventListener;
 import com.vaadin.flow.component.DomEvent;
+import com.vaadin.flow.component.EventData;
 import com.vaadin.flow.component.HasSize;
 import com.vaadin.flow.component.Tag;
 import com.vaadin.flow.component.dependency.HtmlImport;
@@ -181,9 +182,16 @@ public void movePos(int slide) {
   // EVENTS
   @DomEvent("position-changed")
   public static class SlideChangeEvent extends ComponentEvent<Carousel> {
-    public SlideChangeEvent(Carousel source, boolean fromClient) {
+    private String position;
+
+    public SlideChangeEvent(
+        Carousel source, boolean fromClient, @EventData("event.detail.value") String position) {
       super(source, true);
     }
+
+    public String getPosition() {
+      return position;
+    }
   }
 
   public Registration addChangeListener(ComponentEventListener<SlideChangeEvent> listener) {