How do I make a fieldtype use the full column width in the control panel?

Question

I've coded a new fieldtype for my EE3 install. It works, but it doesn't look quite right in the control panel - the input fields only use up half of the available space. This looks fine for many fieldtypes, but I'd rather this stretch across the page, similar to a textarea or grid.

<fieldset class="col-group">
    <div class="setting-txt col w-8">
        <h3><span class="ico sub-arrow"></span>Fieldtype Name</h3>
    </div>
    <div class="setting-field col w-8 last">
        <label for="fto_field_id_21">FieldType Option</label>
        <input type="text" value="" name="field_id_21[fto]">
    </div>
</fieldset>

In Firebug, I can change the class w-8 to w-16 and get the desired look. However, I don't know where in my fieldtype definition I would set that. I dropped the following in my install method:

return array('field_wide' => TRUE);

While it is added to the fieldtype's global settings, it has no effect on how it is displayed in the control panel.

How can I get this full column width fieldtype? Thanks.

Answer 1

You're close! You need to save the field_wide setting for each individual field. You could either do this via a checkbox/radio setting in your field's display_settings method, or simply hard-code the value in your save_settings method:

function save_settings($data)
{
    return array(
        'field_wide' => 'y'
    );
}