Allow menu items to be configured with a callback function directly

(to which any args will be passed), instead of only dispatching
controller commands.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@4465 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/as/com/threerings/mx/controls/CommandMenu.as

@@ -7,18 +7,23 @@ import flash.geom.Rectangle;
 
 import mx.controls.Menu;
 import mx.core.mx_internal;
+import mx.core.ScrollPolicy;
 import mx.events.MenuEvent;
 
 import com.threerings.mx.events.CommandEvent;
 
 /**
  * A pretty standard menu that can submit CommandEvents if menu items
- * have "command" and possibly "arg" properties.
+ * have "command" and possibly "arg" properties. Commands are submitted to
+ * controllers for processing. Alternatively, you may specify
+ * "callback" properties that specify a function closure to call, with the
+ * "arg" property containing either a single arg or an array of args.
  *
  * Example dataProvider array:
  * [ { label: "Go home", icon: homeIconClass,
  *     command: Controller.GO_HOME, arg: homeId },
  *   { type: "separator"},
+     { label: "Crazytown", callback: setCrazy, arg: [ true, false ] },
  *   { label: "Other places", children: subMenuArray }
  * ];
  *
@@ -32,6 +37,7 @@ public class CommandMenu extends Menu
         super();
 
         addEventListener(MenuEvent.ITEM_CLICK, itemClicked);
+//        addEventListener(MenuEvent.MENU_SHOW, handleMenuShown);
     }
 
     /**
@@ -74,14 +80,42 @@ public class CommandMenu extends Menu
      */
     protected function itemClicked (event :MenuEvent) :void
     {
+        var arg :Object = getItemArgument(event.item);
         var cmd :String = getItemCommand(event.item);
-        if (cmd != null) {
+        var fn :Function;
+        if (cmd == null) {
+            fn = getItemCallback(event.item);
+        }
+        if (cmd != null || fn != null) {
             event.stopImmediatePropagation();
-            var arg :Object = getItemArgument(event.item);
-            CommandEvent.dispatch(mx_internal::parentDisplayObject, cmd, arg);
+            if (cmd != null) {
+                CommandEvent.dispatch(mx_internal::parentDisplayObject, cmd, arg);
+
+            } else {
+                try {
+                    var args :Array = (arg as Array);
+                    if (args == null && arg != null) {
+                        args = [ arg ];
+                    }
+                    fn.apply(null, args);
+
+                } catch (err :Error) {
+                    Log.getLog(this).warning("Unable to call menu callback: " +
+                        event.item);
+                }
+            }
         }
     }
 
+//    /**
+//     * Callback for MenuEvent.MENU_SHOW.
+//     */
+//    protected function handleMenuShown (event :MenuEvent) :void
+//    {
+//        // just ensure that every menu can scroll
+//        event.menu.verticalScrollPolicy = ScrollPolicy.ON;
+//    }
+
     /**
      * Get the command for the specified item, if any.
      * Somewhat similar to bits in the DefaultDataDescriptor.
@@ -90,10 +124,29 @@ public class CommandMenu extends Menu
     {
         try {
             if (item is XML) {
-                return String(item.@command);
+                return (item.@command as String);
 
             } else if (item is Object) {
-                return String(item.command);
+                return (item.command as String);
+            }
+        } catch (e :Error) {
+            // fall through
+        }
+
+        return null;
+    }
+
+    /**
+     * Get the callback function for the specified item, if any.
+     */
+    protected function getItemCallback (item :Object) :Function
+    {
+        try {
+            if (item is XML) {
+                return (item.@callback as Function);
+
+            } else if (item is Object) {
+                return (item.callback as Function);
             }
         } catch (e :Error) {
             // fall through