setLeftTitle in Silverstripe 3.1

Question

I have just jumped up the Silverstripe bandwagon. I have been trying to get the following effect of static text in front of a text field on the getCMSfields form:

Telephone number:   +36 [__________]

where "telephone number:" is obviously the field title (which can be altered via ->setTitle() and +36 is a static prefix prepended to the left of the input field.

I have been trying with ->setLeftTitle('+36') but it does not seem to have any effect.

BTW. ->setRightTitle('something') - which I expected to append a label to the right of input field, works identically to ->setDescription().

I'm confused. So is there any way to achieve what I want?

Answer 1

Use the FieldGroup class

public function getCMSFields($fields) {
    $fields = parent::getCMSFields($fields);

    $fields->addFieldToTab('Root.Main',
        FieldGroup::create(
            new HeaderField('+36'),
            new TextField('PhoneNumber','')
        )->setTitle('Telephone number')
    );

    return $fields;
}

Personally I'd use two TextFields for cosmetic reasons, and enforce some validation on the TelephonePrefix.