Passing values to turbogears widgets at display time

In turbogears, I often need to pass data to widgets at display time. Sometimes it works automatically, but sometimes, in cases like passing option lists to CheckBoxLists or number of repetitions in a RepeatingFieldSet, it doesn't.

All the examples use precomputed lists or pass simple code functions. In most of my cases, I want them computed by the controller every time.

Passing a function hasn't worked, as I did not find any obvious way to have the function know about the controller.

So I need to pass things the display() method of the widgets, but I could not work out how to pass the option list and default list for a CheckBoxList that is part of a WidgetsList in a TableForm.

On IRC came the answer, thanks to Xentac:

you should be able to...

And yes, it works. I can pass the default value as one of the normal form values:

    tableform.display(values=dict(checkboxname=[values]), options=dict(checkboxname=[optionlist]))