Checkbox List & mutiple selection

I've added checkboxes to a list component using the cellrenderer however the behavior is different from what i expcted. I'm only able to check one box in the list at a time. I need to be able to check mutiple boxes in the list.

I'm aware you could hold down the control key and select individual the checkboxes, but the application i'm developing is a touch screen aplication hence no keyboard, no control key. I've tried programmaticaly setting the selectedindicies but the checkboxes don't appear checked after the selectedindices have been set.

Any help is appreciated.
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