Method setup

/**
 * Method to attach a Form object to the field.
 *
 * @param   \SimpleXMLElement  $element  The SimpleXMLElement object representing the `<field>` tag for the form field object.
 * @param   mixed              $value    The form field value to validate.
 * @param   string             $group    The field name group control value. This acts as an array container for the field.
 *                                       For example if the field has name="foo" and the group value is set to "bar" then the
 *                                       full field name would end up being "bar[foo]".
 *
 * @return  boolean  True on success.
 *
 * @see 	FormField::setup()
 * @since   3.2
 */
public function setup(\SimpleXMLElement $element, $value, $group = null)
{
    $result = parent::setup($element, $value, $group);
    if ($result === true) {
        $assetField = $this->element['asset_field'] ? (string) $this->element['asset_field'] : 'asset_id';
        $this->authorField = $this->element['created_by_field'] ? (string) $this->element['created_by_field'] : 'created_by';
        $this->asset = $this->form->getValue($assetField) ?: (string) $this->element['asset_id'];
        $this->link = (string) $this->element['link'];
        $this->width = isset($this->element['width']) ? (int) $this->element['width'] : 800;
        $this->height = isset($this->element['height']) ? (int) $this->element['height'] : 500;
        $this->preview = (string) $this->element['preview'];
        $this->directory = (string) $this->element['directory'];
        $this->previewWidth = isset($this->element['preview_width']) ? (int) $this->element['preview_width'] : 200;
        $this->previewHeight = isset($this->element['preview_height']) ? (int) $this->element['preview_height'] : 200;
        $this->types = isset($this->element['types']) ? (string) $this->element['types'] : 'images';
    }
    return $result;
}