I like the new rating field idea really much, but I don't think it really solves the boolean problem. What I will propose has nothing to do with the stars rating system. It's an improvement of the list data type, and it could be used to implement boolean values.
I would like a more restricted List type field, like the one that exists, but where a default user-defined value is used when the field is empty (replaces the undefined or empty value), and where you cannot specify values that are not predefined when you edit an item. In the checkboxes view schemes, all the predefined values should be displayed all the time, whatever the values found in the items listed below.
For example, I use an "iPod" field that I set to "y" or leave empy. When I use a search restriction which gives me only songs where this field is empy, I would like to be able to check the "y" box (which is not displayed). And I would also like the "New iPod value" option not to be displayed.
You could easily build a boolean that way, using "false" (or anything else) as default, and one only other predefined value. You would have 2 checkboxes displayed, though one would be enough. So that's not a exactly what tombert wanted, but it could be a good compromise...
I don't have the time nor the skill to make a mockup like Alex B nice ones... But in the "Configure library field" window, when the List data type is selected, you could just add these items :
- a kind of "No new value" checkbox (prevents the user from creating new ones)
- a "Default value" text field (used when empty)
- a "Display all possible values" checkbox, used in the checkboxes view schemes.
I hope I have been clear enough, quite hard to explain... ^^