♻️ (core) Selectable: add convenience onSelected method and change onSelectionChanged to throw UnsupportedOperationException by default

Author: palexdev

modules/core/src/main/java/io/github/palexdev/mfxcore/popups/menu/MenuBuilder.java

@@ -173,6 +173,10 @@ public CheckMenuBuilder onSelectionChanged(Consumer<Boolean> onSelectionChanged)
             return this;
         }
 
+        public CheckMenuBuilder onSelected(Runnable onSelected) {
+            return onSelectionChanged(s -> {if (s) onSelected.run();});
+        }
+
         public CheckMenuBuilder closeOnAction(boolean closeOnAction) {
             this.closeOnAction = closeOnAction;
             return this;

modules/core/src/main/java/io/github/palexdev/mfxcore/selection/Selectable.java

@@ -70,6 +70,13 @@ default void setSelectionGroup(SelectionGroup group) {
 
     /// Allows specifying a callback to invoke when the selection state of this `Selectable` changes.
     ///
-    /// **This is an optional API. By default, does nothing.**
-    default void onSelectionChanged(Consumer<Boolean> action) {}
+    /// **This is an optional API. By default, throws an `UnsupportedOperationException`.**
+    default void onSelectionChanged(Consumer<Boolean> action) {
+        throw new UnsupportedOperationException("API not implemented by " + getClass());
+    }
+
+    /// Delegate to [#onSelectionChanged(Consumer)] that runs the given action only when selection state is `true`.
+    default void onSelected(Runnable action) {
+        onSelectionChanged(s -> {if (s) action.run();});
+    }
 }