Cannot position my custom picker while editing listgrid row, column item

[michaeljseo]

Cannot place my custom picker at the row,column position of my ListGrid
When I use the code below with a DynamicForm, the iconRect object is not null. When I use this picker on a ListGrid, the iconRect is null. Hence, I cannot get the position to display my custom picker form.

How do I get the location on the ListGrid to display my custom picker/form?

Environment
v8.2p_2012-09-18/PowerEdition Deployment
GWT-2.4

Code Setup
I use ListGrid.setEditorType to add my custom FormItem that has a custom picker. I have a FormItemClickHandler much like the showcase custom picker example. However, getIconPageRect gives me a null object.

myListGrid.getField("update").setEditorType(new FCMDateTimeItem(fname,dsf.getTitle()));

public class FCMDateTimeItem extends DateTimeItem {
	private DateChooser DC;
	private FCMDateTimeItem myself;

	@SuppressWarnings({ "deprecation" })
	private boolean isSameDay(Date d1, Date d2) {
		return d1.getYear() == d2.getYear() && d1.getMonth() == d2.getMonth()
				&& d1.getDate() == d2.getDate();
	}

	private void init()
	{
		myself = this;

		DC = new DateChooser();
		DC.addDataChangedHandler(new DataChangedHandler() {
			@SuppressWarnings("deprecation")
			@Override
			public void onDataChanged(
					com.smartgwt.client.widgets.events.DataChangedEvent event) {
				DC.hide();
				Date now = new Date();
				Date date = DC.getData();
				if (myself.isSameDay(now, date)) {
					date = now;
				} else {
					date.setHours(0);
					date.setMinutes(0);
					date.setSeconds(0);
				}
				// SC.say("Date in setData() :"+date+"<--> Date using getData()"+DC.getData());
				DC.setData(date);
				myself.setValue(date);
			}
		});
		DC.setShowCancelButton(true);
		DC.setCancelButtonTitle("Cancel");
		DC.setTodayButtonTitle("Now");

		PickerIcon datePicker = new PickerIcon(PickerIcon.DATE,
				new FormItemClickHandler() {

					@Override
					public void onFormItemClick(FormItemIconClickEvent event) {
						FormItemIcon fii = event.getIcon();
						Rectangle iconRect = getIconPageRect(fii);
						if(null != iconRect)
						{
							DC.setLeft(iconRect.getLeft());
							DC.setTop(iconRect.getTop());
						}
						else
						{
							//TODO: how to get position for ListGrid
						}
						DC.show();
					}
				});

		this.setShowPickerIcon(false);
		setIcons(datePicker);
	}
	public FCMDateTimeItem() {
		init();
	}
	public FCMDateTimeItem(String name, String title) {
		super(name,title);
		
		init();
	}

}