How to change the bubble chart size at runtime

Hi

I need to display a bunch of symbols on a GIS map . The size of each symbol denotes some value (for example the population of a city). I am using the BubbleChartDataAdapter and it seems to do exactly that.
My problem is that the values are changing over time, but I cannot find a way to update the adapter in order to reflect the change in the symbol's size

Is it possible in general to update the bubbles at runtime or do I have to do something custom?

Here is a very crude example where I try to change the bubble's size when I click on a symbol (working project also attached)

C#
using DevExpress.XtraMap;  

namespace bubble  
{  
    public partial class Form1 : DevExpress.XtraEditors.XtraForm  
    {  
        private MyClass[] MyData;  

        public Form1()  
        {  
            InitializeComponent();  

            bubbles.Data = CreateData();    // bubbles is a VectorItemsLayer  

            mapControl1.MapItemClick += MapControl1OnMapItemClick;  
        }  

        private void MapControl1OnMapItemClick(object sender, MapItemClickEventArgs e)  
        {  
            // trying to edit the source object, not working  
            var obj = bubbles.GetItemSourceObject(e.Item) as MyClass;  
            if (obj != null)  
            {  
                obj.Size += 5;  
            }  

            // changin the bubble's size directly doesnt work either  
            var mb = e.Item as MapBubble;  
            mb.Size += 5;  
        }  

        private IMapDataAdapter CreateData()  
        {  
            MyData = new MyClass[4];  
            MyData[0] = new MyClass { Lat = 36.475, Lon = 70.14, Size = 5 };  
            MyData[1] = new MyClass { Lat = 36.475, Lon = -73.059, Size = 10 };  
            MyData[2] = new MyClass { Lat = -15.877, Lon = -73.059, Size = 15 };  
            MyData[3] = new MyClass { Lat = -15.877, Lon = 70.14, Size = 20 };  

            var adapter = new BubbleChartDataAdapter  
            {  
                DataSource = MyData,  
                ItemMaxSize = 50,  
                ItemMinSize = 10,  
                ValueMember = "Size",  
                LatitudeMember = "Lat",  
                LongitudeMember = "Lon"  
            };  

            return adapter;  
        }  
    }  

    class MyClass  
    {  
        public double Lat { get; set; }  
        public double Lon { get; set; }  
        public double Size { get; set; }  
    }  
}