AmbidextrousList, can have its scrollbar on the left or right side.

In fact, it can be swapped while the user is dragging it...


git-svn-id: svn+ssh://src.earth.threerings.net/nenya/trunk@463 ed5b42cb-e716-0410-a449-f6a68f950b19

src/as/com/threerings/flex/AmbidextrousList.as

@@ -0,0 +1,58 @@
+package com.threerings.flex {
+
+import mx.controls.List;
+
+import mx.core.EdgeMetrics;
+
+/**
+ * A list that can be configured with the vertical scrollbar on the left or right side.
+ */
+public class AmbidextrousList extends List
+{
+    /**
+     * Get whether the scrollbar is on the left side.
+     */
+    public function get scrollBarOnLeft () :Boolean
+    {
+        return _scrollLeft;
+    }
+
+    /**
+     * Sets whether to place the scrollbar on the left or right side.
+     */
+    public function set scrollBarOnLeft (scrollLeft :Boolean) :void
+    {
+        _scrollLeft = scrollLeft;
+
+        scrollAreaChanged = true;
+        invalidateDisplayList();
+    }
+
+    /** @inheritDoc */
+    override public function get viewMetrics () :EdgeMetrics
+    {
+        var em :EdgeMetrics = super.viewMetrics;
+
+        if (_scrollLeft && verticalScrollBar && verticalScrollBar.visible) {
+            em.right -= verticalScrollBar.minWidth;
+            em.left += verticalScrollBar.minWidth;
+        }
+
+        return em;
+    }
+
+    /** @inheritDoc */
+    override protected function updateDisplayList (uw :Number, uh :Number) :void
+    {
+        super.updateDisplayList(uw, uh);
+
+        if (_scrollLeft) {
+            var vm :EdgeMetrics = viewMetrics;
+            verticalScrollBar.move(vm.left - verticalScrollBar.minWidth, vm.top);
+        }
+    }
+
+    /** Do we want to have the scrollbar on the left? */
+    protected var _scrollLeft :Boolean;
+}
+}