I got a grid of type Grid<AbstractModel>. Grid's store is filled with object of type BasicModel<T> which extends AbstractModel. I want a column who can handle input of type <T>, when <T> is String column's cell should be a TextField and when <T> is Date columns' cell should be a TimeFieldCell instead. To make it harder, column's cell should changes based on selected values in other columns. How can I achieve this? Thanks.