Good morning,
I am new with SilverStripe and I have a stupid problem I don't know how to solve. I have this code:

$map = Skill::get()->sort('Name', 'ASC')->map('ID', 'Name');
$fields->addFieldToTab('Root.Covered', new CheckboxSetField($name = "Skills", $title = "Select Covered", $source = $map));

The problem is that the result of that get is to long for display just in one column in admin panel, I would like to display en two columns.

Any tip?

I don't think there's an out of the box solution. Two things I can think of are

1. Check the HTML and see if you can add some styling that would accomplish something like this. You can add a stylesheet to the cms from config.yml, someting like:

LeftAndMain:
  extra_requirements_css:
    - mysite/css/cmscustomstyle.css

2. Create a new CustomCheckboxField extends CheckboxField and give it its own template. You could give it a function that calculates the number of options and then use that value in the template. But that may be a bit complex if you're just starting...

Thanks martimiz! The second solutions worked perfect!

Great!

Just for the record (and anyone else reading this) I meant extending CheckboxSetField - not CheckboxField...