How to hide Text by the check box

I have a checkbox column in my grid which is working. However, there is a trailing text true/false displaying. How can I hide that text? Any idea?
Thanks!

var obj = new AW.UI.Grid;
... ...
... ...
var checkBox = new AW.Templates.Checkbox;
obj.setCellTemplate(checkBox,5);
obj.refresh();

|_| true
|_| False
|_| true
|_| False

obj.setCellText("", 5);