);
columns.setFeatures("lastName", SORTABLE, HIDABLE);
columns.setFeatures("age", SORTABLE, HIDABLE);
columns.setAlignment("age", ALIGN_CENTER);
grid = new LiveDataGrid(columns);
grid.setSize("100%", "250px");
DataSource personDataSource = new PersonDataSource();
grid.setDataSource(personDataSource);
grid.setPageSize(10);