Drupal example source code file (views_handler_filter_boolean_operator.inc)

This example Drupal source code file (views_handler_filter_boolean_operator.inc) is included in the DevDaily.com "Drupal Source Code Warehouse" project. The intent of this project is to help you "Learn Drupal by Example".

PHP - Drupal tags/keywords

any_label, array, else, empty, field, form, function, identifier, if, isset, null, options, php, variable

The views_handler_filter_boolean_operator.inc Drupal example source code

<?php
// $Id: views_handler_filter_boolean_operator.inc,v 1.6.4.8 2010/12/09 23:52:48 merlinofchaos Exp $
/**
 * Simple filter to handle matching of boolean values
 *
 * Definition items:
 * - label: (REQUIRED) The label for the checkbox.
 * - type: For basic 'true false' types, an item can specify the following:
 *    - true-false: True/false (this is the default)
 *    - yes-no: Yes/No
 *    - on-off: On/Off
 * - accept null: Treat a NULL value as false.
 */
class views_handler_filter_boolean_operator extends views_handler_filter {
  // exposed filter options
  var $no_single = TRUE;
  // Don't display empty space where the operator would be.
  var $no_operator = TRUE;
  // Whether to accept NULL as a false value or not
  var $accept_null = FALSE;

  function construct() {
    $this->value_value = t('True');
    if (isset($this->definition['label'])) {
      $this->value_value = $this->definition['label'];
    }
    if (isset($this->definition['accept null'])) {
      $this->accept_null = (bool) $this->definition['accept null'];
    }
    else if (isset($this->definition['accept_null'])) {
      $this->accept_null = (bool) $this->definition['accept_null'];
    }
    $this->value_options = NULL;
    parent::construct();
  }

  /**
   * Return the possible options for this filter.
   *
   * Child classes should override this function to set the possible values
   * for the filter.  Since this is a boolean filter, the array should have
   * two possible keys: 1 for "True" and 0 for "False", although the labels
   * can be whatever makes sense for the filter.  These values are used for
   * configuring the filter, when the filter is exposed, and in the admin
   * summary of the filter.  Normally, this should be static data, but if it's
   * dynamic for some reason, child classes should use a guard to reduce
   * database hits as much as possible.
   */
  function get_value_options() {
    if (isset($this->definition['type'])) {
      if ($this->definition['type'] == 'yes-no') {
        $this->value_options = array(1 => t('Yes'), 0 => t('No'));
      }
      if ($this->definition['type'] == 'on-off') {
        $this->value_options = array(1 => t('On'), 0 => t('Off'));
      }
    }

    // Provide a fallback if the above didn't set anything.
    if (!isset($this->value_options)) {
      $this->value_options = array(1 => t('True'), 0 => t('False'));
    }
  }

  function option_definition() {
    $options = parent::option_definition();

    $options['value']['default'] = FALSE;

    return $options;
  }

  function operator_form(&$form, &$form_state) {
    $form['operator'] = array();
  }

  function value_form(&$form, &$form_state) {
    if (empty($this->value_options)) {
      // Initialize the array of possible values for this filter.
      $this->get_value_options();
    }
    if (!empty($form_state['exposed'])) {
      // Exposed filter: use a select box to save space.
      $filter_form_type = 'select';
    }
    else {
      // Configuring a filter: use radios for clarity.
      $filter_form_type = 'radios';
    }
    $form['value'] = array(
      '#type' => $filter_form_type,
      '#title' => $this->value_value,
      '#options' => $this->value_options,
      '#default_value' => $this->value,
    );
    if (!empty($this->options['exposed'])) {
      $identifier = $this->options['expose']['identifier'];
      if (!empty($form_state['exposed']) && !isset($form_state['input'][$identifier])) {
        $form_state['input'][$identifier] = $this->value;
      }
      // If we're configuring an exposed filter, add an <Any> option.
      if (empty($form_state['exposed']) || !empty($this->options['optional'])) {
        $any_label = variable_get('views_exposed_filter_any_label', 'old_any') == 'old_any' ? '<Any>' : t('- Any -');
        if ($form['value']['#type'] != 'select') {
          $any_label = check_plain($any_label);
        }
        $form['value']['#options'] = array('All' => $any_label) + $form['value']['#options'];
      }
    }
  }

  function value_validate($form, &$form_state) {
    if ($form_state['values']['options']['value'] == 'All' && empty($form_state['values']['options']['expose']['optional'])) {
      form_set_error('value', t('You must select a value unless this is an optional exposed filter.'));
    }
  }

  function admin_summary() {
    if (!empty($this->options['exposed'])) {
      return t('exposed');
    }
    if (empty($this->value_options)) {
      $this->get_value_options();
    }
    // Now that we have the valid options for this filter, just return the
    // human-readable label based on the current value.  The value_options
    // array is keyed with either 0 or 1, so if the current value is not
    // empty, use the label for 1, and if it's empty, use the label for 0.
    return $this->value_options[!empty($this->value)];
  }

  function expose_options() {
    parent::expose_options();
    $this->options['expose']['operator'] = '';
    $this->options['expose']['label'] = $this->value_value;
    $this->options['expose']['optional'] = FALSE;
  }

  function query() {
    $this->ensure_my_table();
    $field = "$this->table_alias.$this->real_field";

    if (empty($this->value)) {
      if ($this->accept_null) {
        $or = db_or()
          ->condition($field, 0, '=')
          ->condition($field, NULL, 'IS NULL');
        $this->query->add_where($this->options['group'], $or);
      }
      else {
        $this->query->add_where($this->options['group'], $field, 0, '=');
      }
    }
    else {
      if (!empty($this->definition['use equal'])) {
        $this->query->add_where($this->options['group'], $field, 1, '=');
      }
      else {
        $this->query->add_where($this->options['group'], $field, 0, '<>');
      }
    }
  }
}