Bug: editing nullable boolean forces it to false

[sedubois]

When a model has a boolean which can be nil, the "Show" tab indeed shows the boolean as nil with the help of a grey icon:

However in the Edit tab, the value is displayed as an unticked checkbox instead of reflecting the fact that the value is nil:

And when saving the Edit form, it then applies the value false to the field, instead of keeping it nil as it should. It means that currently I cannot use rails_admin to edit my records' other fields, out of fear of inadvertently modifying these boolean values which should stay nil.

[RocKhalil]

What's the difference between having a boolean set as nil or false ? both cases it's a false statement.

[sedubois]

nil can be used to represent the absence of information, false represents information. Anyway the Ruby language itself allows booleans fields to have those 3 values, just as many other languages allow as well. At the very least the editor shouldn't coerce nil fields into false.

[RocKhalil]

Yup, totally get that. However, how can you know if the value was set by the user as false or as nil ? Maybe having a dropdown is a better option than a checkbox ?

[sedubois]

Maybe use 3 radio buttons?

[RocKhalil]

Good idea;

When nullable is set to false, we can use checkbox; otherwise, 3 radio buttons 👍

[nick-bigger]

I ran into this same issue! While it is being worked on, I have a basic workaround:

field :boolean_field, :enum do
  enum do
      [['True',true],['False',false],['Null',nil]]
  end
end

Unfortunately, no option will show in the dropdown for 'Null', but the field will show 'Optional' and can be cleared and saved correctly. And on the show page 'Null' will show correctly. Hope this helps!

[yuvalt]

What worked for me is:

def boolean_field_enum
    [['True',true],['False',false],['Null',nil]]
end