Created a base Controller class; added a CommandButton that submits

controller commands; have PlaceController extend Controller.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@4275 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/as/com/threerings/util/Controller.as

@@ -0,0 +1,58 @@
+package com.threerings.util {
+
+import flash.events.IEventDispatcher;
+
+import com.threerings.events.ControllerEvent;
+
+public class Controller
+{
+    /**
+     * Set the panel being controlled.
+     */
+    protected function setControlledPanel (panel :IEventDispatcher) :void
+    {
+        if (_panel != null) {
+            _panel.removeEventListener(
+                ControllerEvent.TYPE, handleControllerEvent);
+        }
+        _panel = panel;
+        if (_panel != null) {
+            _panel.addEventListener(
+                ControllerEvent.TYPE, handleControllerEvent);
+        }
+    }
+
+    /**
+     * Handle an action that was generated by our panel or some child.
+     *
+     * @return true if the specified action was handled, false otherwise.
+     *
+     * When creating your own controller, override this function and return
+     * true for any command handled, and call super for any unknown commands.
+     */
+    public function handleAction (cmd :String, arg :Object) :Boolean
+    {
+        // TODO: This warning should really be inside the ControllerEvent
+        // somewhere, and only generated if the event never gets cancelled
+        Log.getLog(this).warning("Unhandled controller command " +
+            "[cmd=" + cmd + ", arg=" + arg + "].");
+        return false; // not handled
+    }
+
+    /**
+     * Private function to handle the controller event and call
+     * handleAction.
+     */
+    private function handleControllerEvent (event :ControllerEvent) :void
+    {
+        if (handleAction(event.command, event.arg)) {
+            // if we handle the event, stop it from moving outward to another
+            // controller
+            event.stopImmediatePropagation();
+        }
+    }
+
+    /** The panel currently being controlled. */
+    private var _panel :IEventDispatcher; 
+}
+}