Search Help + Read only field

Hi there,

I need to lay out an input field with a search help but I want to make sure that all the entries entered in the input field are exactly those allowed by the search help.

I therefore assigned the property enabled to false and readonly to false as well but in this case the search help is not active (cannot be called) because the field is treated like a simple textview with no input help.

How can this be achieved?

Thanks