When creating a fieldtype how do I provide methods to be used in the templates?

Question

I have created a fieldtype that saves a single integer to the database, it has some settings that defines the maximum value that integer can be:

protected function defineSettings()
{
  return array(
    'maxNumber' => array(AttributeType::Number, 'min' => 2, 'default' => 12)
  );
}

What I want to do when outputting my field in the templates is something like this:

The value is {{ entry.myField }} of {{ entry.myField.maxNumber }}

Anyone have any ideas? Do I need to create a data class like the options-based fields use or something? I'm just stabbing around in the dark here...

Answer 1

Like plugins, fieldtypes can have their own settings as you're aware but while you can grab your plugin settings from pretty much anywhere, fieldtypes are a little more contextual.

In any case, like @Bryan pointed out, your fieldtype needs to implement prepValue($value) and ideally return a model containing the value as defined in defineAttributes() and the maxNumber as a property.

This basically means that when Craft calls your fieldtype's prepValue($value) which it does when the value of your field is needed (editing/outputting) you can return a model with the value and maxNumber.

---

EDIT:

// MyFieldType.php
public function prepValue($value)
{
    $model = new MyFieldModel;

    $model->setAttribute('value', $value);
    $model->setMaxNumber($this->getSettings()->getAttribute('maxNumber'));

    return $model;
}

// MyFieldModel.php
// Explicit getter/setter for $maxNumber rather than defining it as an attribute
protected $maxNumber;

public function setMaxNumber($value)
{
    $this->maxNumber = $value;
}

public function getMaxNumber()
{
    return $this->maxNumber;
}

public function defineAttributes()
{
    return array(
        'value' => AttributeType::Number,
    );
}

// _entry.html or other template name
{{ entry.myFieldHandle.value }}
{{ entry.myFieldHandle.maxNumber }}

@selvinortiz

Answer 2

To do this as you describe, you would need to add the prepValue function to your field type. You would then need to create a PHP class to fill with your field value and settings.

I'm not sure that it would work, but I also suggest adding the __invoke() method. You could use it to return the field value when you use the object as a variable (though Twig would call it as a method I think).