Edit documentation exemples

docs/maps/api-ui.md

@@ -49,7 +49,7 @@ Example:
 let helloWorldPopup;
 
 // Open the popup when we enter a given zone
-helloWorldPopup = WA.room.onEnterZone('myZone', () => {
+helloWorldPopup = WA.room.onEnterLayer("myZone").subscribe(() => {
     WA.ui.openPopup("popupRectangle", 'Hello world!', [{
         label: "Close",
         className: "primary",
@@ -57,13 +57,13 @@ helloWorldPopup = WA.room.onEnterZone('myZone', () => {
             // Close the popup when the "Close" button is pressed.
             popup.close();
         }
-    });
-}]);
+    }]);
+});
 
 // Close the popup when we leave the zone.
-WA.room.onLeaveZone('myZone', () => {
+WA.room.onLeaveLayer("myZone").subscribe(() => {
     helloWorldPopup.close();
-});
+})
 ```
 
 ### Add custom menu