Problem with ColumnChart Clickevent

I use ColumnChart component for my application

I don’t know how to get (event + data) when user click on a column


			if (Data.size() > 0) {
				ColumnChart ccPeriodMaintenance = new ColumnChart();
				ccPeriodMaintenance.setOption("is3D", true);
				ccPeriodMaintenance.setOption("width", 1000);

				ccPeriodMaintenance.addXAxisLabel("Month");
				ccPeriodMaintenance.addColumn("thu"); //column thu
				ccPeriodMaintenance.addColumn("chi");// column chi

				for (T900 t900 : Data) {
					if (t900 == null)
						continue;
					String project = t900.getBv051();
					iteam = t900;
					ccPeriodMaintenance.add(project,
							new double[] { t900.getThu(), t900.getChi() });
				}
....

when user click I want to know get column name ( thu or chi) and some data of this column