Making possible setting ConnectorResource resources as icons (#104)

* Making possible setting ConnectorResource resources as icons

Fixes #17

* Update example

* Instantiate VerticalLayout inside init method

vaadin-context-menu-addon/src/main/java/com/vaadin/contextmenu/ContextMenu.java

@@ -25,6 +25,7 @@
 import com.vaadin.event.ContextClickEvent.ContextClickListener;
 import com.vaadin.event.ContextClickEvent.ContextClickNotifier;
 import com.vaadin.server.AbstractExtension;
+import com.vaadin.server.ConnectorResource;
 import com.vaadin.server.Extension;
 import com.vaadin.server.Resource;
 import com.vaadin.server.ResourceReference;
@@ -170,8 +171,12 @@ private List<ContextMenuItemState> convertItemsToState(List<MenuItem> items,
                     .getDescriptionContentMode();
             menuItemState.enabled = item.isEnabled();
             menuItemState.separator = item.isSeparator();
-            menuItemState.icon = ResourceReference.create(item.getIcon(), this,
-                    "");
+            String key="icon";
+            ResourceReference resourceReference = ResourceReference.create(item.getIcon(), this, key);
+            if (item.getIcon()!=null && (item.getIcon() instanceof ConnectorResource)) {
+                super.getState().resources.put(key,resourceReference);
+            }
+            menuItemState.icon = resourceReference;
             menuItemState.styleName = item.getStyleName();
 
             menuItemState.childItems = convertItemsToState(item.getChildren(),

vaadin-context-menu-demo/src/main/java/com/vaadin/contextmenu/ContextMenuUI.java

@@ -10,6 +10,8 @@
 import com.vaadin.server.BrowserWindowOpener;
 import com.vaadin.server.VaadinRequest;
 import com.vaadin.server.VaadinServlet;
+import com.vaadin.server.ClassResource;
+import com.vaadin.server.ThemeResource;
 import com.vaadin.ui.Button;
 import com.vaadin.ui.MenuBar.MenuItem;
 import com.vaadin.ui.Notification;
@@ -69,7 +71,9 @@ private void addTree(VerticalLayout layout) {
         TreeContextMenu<String> treeContextMenu = new TreeContextMenu<>(tree);
         treeContextMenu.addTreeContextMenuListener(e -> {
             treeContextMenu.removeItems();
-            treeContextMenu.addItem("Who?", menuItem -> Notification.show(e.getItem()));
+            //The path is /resources/images/kitten.jpg
+            ClassResource ico = new ClassResource("/images/kitten.jpg");
+            treeContextMenu.addItem("Who?",ico, menuItem -> Notification.show(e.getItem()));
         });
 
         layout.addComponent(tree);
@@ -95,19 +99,24 @@ private void fillMenu(ContextMenu menu) {
 
         menu.addSeparator();
 
-        MenuItem item4 = menu.addItem("Icon + Description + <b>HTML</b>",
+        //The path is /resources/images/kitten.jpg
+        ClassResource ico = new ClassResource("/images/kitten.jpg");
+        MenuItem item4 = menu.addItem("Icon + Description + <b>HTML</b>",ico,
                 e -> Notification.show("icon")
         );
-        item4.setIcon(VaadinIcons.ADJUST);
         item4.setDescription("Test tooltip");
         but3.addClickListener(e -> item4.setDescription(""));
         MenuItem item5 = menu.addItem("Custom stylename",
                 e -> Notification.show("stylename")
         );
+        //The path is /webapp/VAADIN/themes/contextmenu/images
+        ThemeResource resource = new ThemeResource("images/cat.jpg");
+        item5.setIcon(resource);
+
         item5.setStyleName("teststyle");
 
         MenuItem item6 = menu.addItem("Submenu");
-        item6.addItem("Subitem", e -> Notification.show("SubItem"));
+        item6.addItem("Subitem", VaadinIcons.OPTION, e -> Notification.show("SubItem"));
         item6.addSeparator();
         item6.addItem("Subitem", e -> Notification.show("SubItem"))
                 .setDescription("Test");