Bring back the scrollable menu. However, we leave the default as not scrolling, and only do

scrolling of any kind of the verticalScrollPolicy is set to ScrollPolicy.AUTO or ScrollPolicy.ON, 
and the maxHeight has been set.


git-svn-id: svn+ssh://src.earth.threerings.net/nenya/trunk@525 ed5b42cb-e716-0410-a449-f6a68f950b19

src/as/com/threerings/flex/CommandMenu.as

@@ -23,6 +23,8 @@ package com.threerings.flex {
 
 import flash.display.DisplayObject;
 import flash.display.DisplayObjectContainer;
+
+import flash.events.Event;
 import flash.events.IEventDispatcher;
 
 import flash.geom.Point;
@@ -98,6 +100,35 @@ public class CommandMenu extends Menu
         return menu;
     }
 
+    /**
+     * The mx.controls.Menu class overrides setting and getting the verticalScrollPolicy
+     * basically setting the verticalScrollPolicy did nothing, and getting it always returned
+     * ScrollPolicy.OFF.  So that's not going to work if we want the menu to scroll. Here we 
+     * reinstate the verticalScrollPolicy setter, and keep a local copy of the value in a 
+     * protected variable _verticalScrollPolicy.
+     * 
+     * This setter is basically a copy of what ScrollControlBase and ListBase do.
+     */
+    override public function set verticalScrollPolicy (value :String) :void 
+    {
+        var newPolicy :String = value.toLowerCase();
+
+        itemsSizeChanged = true;
+
+        if (_verticalScrollPolicy != newPolicy)
+        {
+            _verticalScrollPolicy = newPolicy;
+            dispatchEvent(new Event("verticalScrollPolicyChanged"));
+        }
+
+        invalidateDisplayList();
+    }
+
+    override public function get verticalScrollPolicy () :String
+    {
+        return _verticalScrollPolicy;
+    }
+
     public function CommandMenu ()
     {
         super();
@@ -188,6 +219,52 @@ public class CommandMenu extends Menu
         PopUpUtil.fitInRect(this, _fitting || screen);
     }
 
+    /** 
+     * The Menu class overrode configureScrollBars() and made the function do nothing.  That means
+     * the scrollbars don't know how to draw themselves, so here we reinstate configureScrollBars.
+     * This is basically a copy of the same method from the mx.controls.List class.
+     */
+    override protected function configureScrollBars () :void
+    {
+        var rowCount :int = listItems.length;
+        if (rowCount == 0) {
+            return;
+        }
+
+        // if there is more than one row and it is a partial row we don't count it
+        if (rowCount > 1 && 
+            rowInfo[rowCount - 1].y + rowInfo[rowCount - 1].height > listContent.height) {
+            rowCount--;
+        }
+
+        // offset, when added to rowCount, is hte index of the dataProvider item for that row.  
+        // IOW, row 10 in listItems is showing dataProvider item 10 + verticalScrollPosition - 
+        // lockedRowCount - 1
+        var offset :int = verticalScrollPosition - lockedRowCount - 1;
+
+        // don't count filler rows at the bottom either.
+        var fillerRows :int = 0;
+        while (rowCount > 0 && listItems[rowCount - 1].length == 0)
+        {
+            if (collection && rowCount + offset >= collection.length) {
+                rowCount--;
+                fillerRows++;
+            } else {
+                break;
+            }
+        }
+
+        var colCount :int = listItems[0].length;
+        var oldHorizontalScrollBar :Object = horizontalScrollBar;
+        var oldVerticalScrollBar :Object = verticalScrollBar;
+        var roundedWidth :int = Math.round(unscaledWidth);
+        var length :int = collection ? collection.length - lockedRowCount : 0;
+        var numRows :int = rowCount - lockedRowCount;
+
+        setScrollBarProperties(Math.round(listContent.width), roundedWidth, length, numRows);
+        maxVerticalScrollPosition = Math.max(length - numRows, 0);
+    }
+
     /**
      * Callback for MenuEvent.ITEM_CLICK.
      */
@@ -265,6 +342,23 @@ public class CommandMenu extends Menu
         PopUpUtil.fitInRect(submenu, _fitting || screen);
     }
 
+    override protected function measure () :void
+    {
+        super.measure();
+
+        if (measuredHeight > this.maxHeight) {
+            measuredHeight = this.maxHeight;
+        }
+
+        if (verticalScrollPolicy == ScrollPolicy.ON || verticalScrollPolicy == ScrollPolicy.AUTO) {
+            if (verticalScrollBar) {
+                measuredMinWidth = measuredWidth = measuredWidth + verticalScrollBar.minWidth;
+            }
+        }
+
+        commitProperties();
+    }
+
     // from List
     override protected function makeListData (data :Object, uid :String, rowNum :int) :BaseListData
     {
@@ -316,5 +410,6 @@ public class CommandMenu extends Menu
     protected var _lefting :Boolean = false;
     protected var _upping :Boolean = false;
     protected var _fitting :Rectangle = null;
+    protected var _verticalScrollPolicy :String;
 }
 }