fix getting page size

Author: ianharrigan

haxe/ui/containers/ScrollView.hx

@@ -478,6 +478,14 @@ private class HScrollPageSize extends DataBehaviour {
         _scrollview = scrollview;
     }
 
+    public override function get():Variant {
+        var hscroll = _scrollview.findComponent(HorizontalScroll, false);
+        if (hscroll == null) {
+            return 0;
+        }
+        return hscroll.pageSize;
+    }
+
     public override function validateData() { // TODO: feels a bit ugly!
         if (_scrollview.virtual == true) {
             var hscroll = _scrollview.findComponent(HorizontalScroll, false);
@@ -524,6 +532,14 @@ private class VScrollPageSize extends DataBehaviour {
         _scrollview = scrollview;
     }
 
+    public override function get():Variant {
+        var vscroll = _scrollview.findComponent(VerticalScroll, false);
+        if (vscroll == null) {
+            return 0;
+        }
+        return vscroll.pageSize;
+    }
+
     public override function validateData() { // TODO: feels a bit ugly!
         if (_scrollview.virtual == true) {
             var vscroll = _scrollview.findComponent(VerticalScroll, false);