home | career | drupal | java | mac | mysql | perl | php | scala | uml | unix

Drupal example source code file (views.module)

This example Drupal source code file (views.module) 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

array, as, display_id, empty, file, foreach, function, if, name, null, php, return, view, views

The views.module Drupal example source code

<?php
// $Id: views.module,v 1.341.2.12 2010/04/29 18:26:04 merlinofchaos Exp $
/**
 * @file
 * Primarily Drupal hooks and global API functions to manipulate views.
 *
 * This is the main module file for Views. The main entry points into
 * this module are views_page() and views_block(), where it handles
 * incoming page and block requests.
 */

/**
 * Advertise the current views api version
 */
function views_api_version() {
  return 2.0;
}

/**
 * Implementation of hook_init().
 */
function views_init() {
  drupal_add_css(drupal_get_path('module', 'views') . '/css/views.css');
}

/**
 * Implementation of hook_theme(). Register views theming functions.
 */
function views_theme() {
  $path = drupal_get_path('module', 'views');
  require_once "./$path/theme/theme.inc";

  // Some quasi clever array merging here.
  $base = array(
    'file' => 'theme.inc',
    'path' => "$path/theme",
  );

  // Our extra version of pager from pager.inc
  $hooks['views_mini_pager'] = $base + array(
    'arguments' => array('tags' => array(), 'limit' => 10, 'element' => 0, 'parameters' => array()),
    'pattern' => 'views_mini_pager__',
  );

  $arguments = array(
    'display' => array('view' => NULL),
    'style' => array('view' => NULL, 'options' => NULL, 'rows' => NULL, 'title' => NULL),
    'row' => array('view' => NULL, 'options' => NULL, 'row' => NULL, 'field_alias' => NULL),
  );

  // Default view themes
  $hooks['views_view_field'] = $base + array(
    'pattern' => 'views_view_field__',
    'arguments' => array('view' => NULL, 'field' => NULL, 'row' => NULL),
  );

  $plugins = views_fetch_plugin_data();

  // Register theme functions for all style plugins
  foreach ($plugins as $type => $info) {
    foreach ($info as $plugin => $def) {
      if (isset($def['theme'])) {
        $hooks[$def['theme']] = array(
          'pattern' => $def['theme'] . '__',
          'file' => $def['theme file'],
          'path' => $def['theme path'],
          'arguments' => $arguments[$type],
        );

        $include = './' . $def['theme path'] . '/' . $def['theme file'];
        if (file_exists($include)) {
          require_once $include;
        }

        if (!function_exists('theme_' . $def['theme'])) {
          $hooks[$def['theme']]['template'] = views_css_safe($def['theme']);
        }
      }
      if (isset($def['additional themes'])) {
        foreach ($def['additional themes'] as $theme => $theme_type) {
          if (empty($theme_type)) {
            $theme = $theme_type;
            $theme_type = $type;
          }

          $hooks[$theme] = array(
            'pattern' => $theme . '__',
            'file' => $def['theme file'],
            'path' => $def['theme path'],
            'arguments' => $arguments[$theme_type],
          );

          if (!function_exists('theme_' . $theme)) {
            $hooks[$theme]['template'] = views_css_safe($theme);
          }
        }
      }
    }
  }

  $hooks['views_exposed_form'] = $base + array(
    'template' => 'views-exposed-form',
    'pattern' => 'views_exposed_form__',
    'arguments' => array('form' => NULL),
  );

  $hooks['views_more'] = $base + array(
    'template' => 'views-more',
    'pattern' => 'views_more__',
    'arguments' => array('more_url' => NULL, 'link_text' => 'more'),
  );
  return $hooks;
}

/**
 * A theme preprocess function to automatically allow view-based node
 * templates if called from a view.
 *
 * The 'modules/node.views.inc' file is a better place for this, but
 * we haven't got a chance to load that file before Drupal builds the
 * node portion of the theme registry.
 */
function views_preprocess_node(&$vars) {
  // The 'view' attribute of the node is added in template_preprocess_views_view_row_node()
  if (!empty($vars['node']->view) && !empty($vars['node']->view->name)) {
    $vars['view'] = &$vars['node']->view;
    $vars['template_files'][] = 'node-view-' . $vars['node']->view->name;
    if(!empty($vars['node']->view->current_display)) {
      $vars['template_files'][] = 'node-view-' . $vars['node']->view->name . '-' . $vars['node']->view->current_display;
    }
  }
}

/**
 * A theme preprocess function to automatically allow view-based node
 * templates if called from a view.
 */
function views_preprocess_comment(&$vars) {
  // The 'view' attribute of the node is added in template_preprocess_views_view_row_comment()
  if (!empty($vars['node']->view) && !empty($vars['node']->view->name)) {
    $vars['view'] = &$vars['node']->view;
    $vars['template_files'][] = 'comment-view-' . $vars['node']->view->name;
    if(!empty($vars['node']->view->current_display)) {
      $vars['template_files'][] = 'comment-view-' . $vars['node']->view->name . '-' . $vars['node']->view->current_display;
    }
  }
}

/*
 * Implementation of hook_perm()
 */
function views_perm() {
  return array('access all views', 'administer views');
}

/**
 * Implementation of hook_menu().
 */
function views_menu() {
  // Any event which causes a menu_rebuild could potentially mean that the
  // Views data is updated -- module changes, profile changes, etc.
  views_invalidate_cache();
  $items = array();
  $items['views/ajax'] = array(
    'title' => 'Views',
    'page callback' => 'views_ajax',
    'access callback' => TRUE,
    'description' => 'Ajax callback for view loading.',
    'file' => 'includes/ajax.inc',
    'type' => MENU_CALLBACK,
  );
  // Path is not admin/build/views due to menu complications with the wildcards from
  // the generic ajax callback.
  $items['admin/views/ajax/autocomplete/user'] = array(
    'page callback' => 'views_ajax_autocomplete_user',
    'access callback' => 'user_access',
    'access arguments' => array('access content'),
    'file' => 'includes/ajax.inc',
    'type' => MENU_CALLBACK,
  );
  return $items;
}

/**
 * Implementation of hook_menu_alter().
 */
function views_menu_alter(&$callbacks) {
  $our_paths = array();
  $views = views_get_applicable_views('uses hook menu');
  foreach ($views as $data) {
    list($view, $display_id) = $data;
    $result = $view->execute_hook_menu($display_id, $callbacks);
    if (is_array($result)) {
      // The menu system doesn't support having two otherwise
      // identical paths with different placeholders.  So we
      // want to remove the existing items from the menu whose
      // paths would conflict with ours.

      // First, we must find any existing menu items that may
      // conflict.  We use a regular expression because we don't
      // know what placeholders they might use.  Note that we
      // first construct the regex itself by replacing %views_arg
      // in the display path, then we use this constructed regex
      // (which will be something like '#^(foo/%[^/]*/bar)$#') to
      // search through the existing paths.
      $regex = '#^(' . preg_replace('#%views_arg#', '%[^/]*', implode('|', array_keys($result))) . ')$#';
      $matches = preg_grep($regex, array_keys($callbacks));

      // Remove any conflicting items that were found.
      foreach ($matches as $path) {
        // Don't remove the paths we just added!
        if (!isset($our_paths[$path])) {
          unset($callbacks[$path]);
        }
      }
      foreach ($result as $path => $item) {
        if (!isset($callbacks[$path])) {
          // Add a new item, possibly replacing (and thus effectively
          // overriding) one that we removed above.
          $callbacks[$path] = $item;
        }
        else {
          // This item already exists, so it must be one that we added.
          // We change the various callback arguments to pass an array
          // of possible display IDs instead of a single ID.
          $callbacks[$path]['page arguments'][1] = (array)$callbacks[$path]['page arguments'][1];
          $callbacks[$path]['page arguments'][1][] = $display_id;
          $callbacks[$path]['access arguments'][] = $item['access arguments'][0];
          $callbacks[$path]['load arguments'][1] = (array)$callbacks[$path]['load arguments'][1];
          $callbacks[$path]['load arguments'][1][] = $display_id;
        }
        $our_paths[$path] = TRUE;
      }
    }
  }

  // Save memory: Destroy those views.
  foreach ($views as $data) {
    list($view, $display_id) = $data;
    $view->destroy();
  }
}

/**
 * Helper function for menu loading. This will automatically be
 * called in order to 'load' a views argument; primarily it
 * will be used to perform validation.
 *
 * @param $value
 *   The actual value passed.
 * @param $name
 *   The name of the view. This needs to be specified in the 'load function'
 *   of the menu entry.
 * @param $index
 *   The menu argument index. This counts from 1.
 */
function views_arg_load($value, $name, $display_id, $index) {
  if ($view = views_get_view($name)) {
    $view->set_display($display_id);
    $view->init_handlers();

    $ids = array_keys($view->argument);

    $indexes = array();
    $path = explode('/', $view->get_path());

    foreach ($path as $id => $piece) {
      if ($piece == '%' && !empty($ids)) {
        $indexes[$id] = array_shift($ids);
      }
    }

    if (isset($indexes[$index])) {
      if (isset($view->argument[$indexes[$index]])) {
        $arg = $view->argument[$indexes[$index]]->validate_argument($value) ? $value : FALSE;
        $view->destroy();
        return $arg;
      }
    }
    $view->destroy();
  }
}

/**
 * Page callback entry point; requires a view and a display id, then
 * passes control to the display handler.
 */
function views_page() {
  $args = func_get_args();
  $name = array_shift($args);
  $display_id = array_shift($args);

  // Load the view
  if ($view = views_get_view($name)) {
    return $view->execute_display($display_id, $args);
  }

  // Fallback; if we get here no view was found or handler was not valid.
  return drupal_not_found();
}

/**
 * Implementation of hook_block
 */
function views_block($op = 'list', $delta = 0, $edit = array()) {
  switch ($op) {
    case 'list':
      $items = array();
      $views = views_get_all_views();
      foreach ($views as $view) {
        // disabled views get nothing.
        if (!empty($view->disabled)) {
          continue;
        }

        $view->init_display();
        foreach ($view->display as $display_id => $display) {

          if (isset($display->handler) && !empty($display->handler->definition['uses hook block'])) {
            $result = $display->handler->execute_hook_block();
            if (is_array($result)) {
              $items = array_merge($items, $result);
            }
          }

          if (isset($display->handler) && $display->handler->get_option('exposed_block')) {
            $result = $display->handler->get_special_blocks();
            if (is_array($result)) {
              $items = array_merge($items, $result);
            }
          }
        }
      }

      // block.module has a delta length limit of 32, but our deltas can
      // unfortunately be longer because view names can be 32 and display IDs
      // can also be 32. So for very long deltas, change to md5 hashes.
      $hashes = array();

      // get the keys because we're modifying the array and we don't want to
      // confuse PHP too much.
      $keys = array_keys($items);
      foreach ($keys as $delta) {
        if (strlen($delta) >= 32) {
          $hash = md5($delta);
          $hashes[$hash] = $delta;
          $items[$hash] = $items[$delta];
          unset($items[$delta]);
        }
      }

      // Only save hashes if they have changed.
      $old_hashes = variable_get('views_block_hashes', array());
      if ($hashes != $old_hashes) {
        variable_set('views_block_hashes', $hashes);
      }
      // Save memory: Destroy those views.
      foreach ($views as $view) {
        $view->destroy();
      }

      return $items;
    case 'view':
      $start = views_microtime();
      // if this is 32, this should be an md5 hash.
      if (strlen($delta) == 32) {
        $hashes = variable_get('views_block_hashes', array());
        if (!empty($hashes[$delta])) {
          $delta = $hashes[$delta];
        }
      }

      // This indicates it's a special one.
      if (substr($delta, 0, 1) == '-') {
        list($nothing, $type, $name, $display_id) = explode('-', $delta);
        // Put the - back on.
        $type = '-' . $type;
        if ($view = views_get_view($name)) {
          if ($view->access($display_id)) {
            $view->set_display($display_id);
            if (isset($view->display_handler)) {
              $output = $view->display_handler->view_special_blocks($type);
              $view->destroy();
              return $output;
            }
          }
          $view->destroy();
        }
      }

      list($name, $display_id) = explode('-', $delta);
      // Load the view
      if ($view = views_get_view($name)) {
        if ($view->access($display_id)) {
          $output = $view->execute_display($display_id);
          vpr("Block $view->name execute time: " . (views_microtime() - $start) * 1000 . "ms");
          $view->destroy();
          return $output;
        }
        $view->destroy();
      }
      break;
  }
}

/**
 * Implementation of hook_flush_caches().
 */
function views_flush_caches() {
  return array('cache_views', 'cache_views_data');
}

/**
 * Invalidate the views cache, forcing a rebuild on the next grab of table data.
 */
function views_invalidate_cache() {
  cache_clear_all('*', 'cache_views', true);
}

/**
 * Access callback to determine if the user can import Views.
 *
 * View imports require an additional access check because they are PHP
 * code and PHP is more locked down than administer views.
 */
function views_import_access() {
  return user_access('administer views') && user_access('use PHP for block visibility');
}

/**
 * Determine if the logged in user has access to a view.
 *
 * This function should only be called from a menu hook or some other
 * embedded source. Each argument is the result of a call to
 * views_plugin_access::get_access_callback() which is then used
 * to determine if that display is accessible. If *any* argument
 * is accessible, then the view is accessible.
 */
function views_access() {
  $args = func_get_args();
  foreach ($args as $arg) {
    if ($arg === TRUE) {
      return TRUE;
    }

    if (!is_array($arg)) {
      continue;
    }

    list($callback, $arguments) = $arg;
    if (function_exists($callback) && call_user_func_array($callback, $arguments)) {
      return TRUE;
    }
  }

  return FALSE;
}

/**
 * Access callback for the views_plugin_access_perm access plugin.
 *
 * Determine if the specified user has access to a view on the basis of
 * permissions. If the $account argument is omitted, the current user
 * is used.
 */
function views_check_perm($perm, $account = NULL) {
  return user_access($perm, $account) || user_access('access all views', $account);
}

/**
 * Access callback for the views_plugin_access_role access plugin.

 * Determine if the specified user has access to a view on the basis of any of
 * the requested roles. If the $account argument is omitted, the current user
 * is used.
 */
function views_check_roles($rids, $account = NULL) {
  global $user;
  $account = isset($account) ? $account : $user;
  $roles = array_keys($account->roles);
  $roles[] = $account->uid ? DRUPAL_AUTHENTICATED_RID : DRUPAL_ANONYMOUS_RID;
  return user_access('access all views', $account) || array_intersect(array_filter($rids), $roles);
}
// ------------------------------------------------------------------
// Functions to help identify views that are running or ran

/**
 * Set the current 'page view' that is being displayed so that it is easy
 * for other modules or the theme to identify.
 */
function &views_set_page_view($view = NULL) {
  static $cache = NULL;
  if (isset($view)) {
    $cache = $view;
  }

  return $cache;
}

/**
 * Find out what, if any, page view is currently in use. Please note that
 * this returns a reference, so be careful! You can unintentionally modify the
 * $view object.
 */
function &views_get_page_view() {
  return views_set_page_view();
}

/**
 * Set the current 'current view' that is being built/rendered so that it is
 * easy for other modules or items in drupal_eval to identify
 */
function &views_set_current_view($view = NULL) {
  static $cache = NULL;
  if (isset($view)) {
    $cache = $view;
  }

  return $cache;
}

/**
 * Find out what, if any, current view is currently in use. Please note that
 * this returns a reference, so be careful! You can unintentionally modify the
 * $view object.
 */
function &views_get_current_view() {
  return views_set_current_view();
}

// ------------------------------------------------------------------
// Include file helpers

/**
 * Include views .inc files as necessary.
 */
function views_include($file) {
  static $used = array();
  if (!isset($used[$file])) {
    require_once './' . drupal_get_path('module', 'views') . "/includes/$file.inc";
  }

  $used[$file] = TRUE;
}

/**
 * Load views files on behalf of modules.
 */
function views_module_include($file) {
  foreach (views_get_module_apis() as $module => $info) {
    if (file_exists("./$info[path]/$module.$file")) {
      require_once "./$info[path]/$module.$file";
    }
  }
}

/**
 * Get a list of modules that support the current views API.
 */
function views_get_module_apis() {
  static $cache = NULL;
  if (!isset($cache)) {
    $cache = array();
    foreach (module_implements('views_api') as $module) {
      $function = $module . '_views_api';
      $info = $function();
      if (isset($info['api']) && $info['api'] == 2.000) {
        if (!isset($info['path'])) {
          $info['path'] = drupal_get_path('module', $module);
        }
        $cache[$module] = $info;
      }
    }
  }

  return $cache;
}

/**
 * Include views .css files.
 */
function views_add_css($file) {
  // We set preprocess to FALSE because we are adding the files conditionally,
  // and we don't want to generate duplicate cache files.
  // TODO: at some point investigate adding some files unconditionally and
  // allowing preprocess.
  drupal_add_css(drupal_get_path('module', 'views') . "/css/$file.css", 'module', 'all', FALSE);
}

/**
 * Include views .js files.
 */
function views_add_js($file) {
  // If javascript has been disabled by the user, never add js files.
  if (variable_get('views_no_javascript', FALSE)) {
    return;
  }

  static $base = TRUE;
  if ($base) {
    drupal_add_js(drupal_get_path('module', 'views') . "/js/base.js");
    $base = FALSE;
  }
  drupal_add_js(drupal_get_path('module', 'views') . "/js/$file.js");
}

/**
 * Load views files on behalf of modules.
 */
function views_include_handlers() {
  static $finished = FALSE;
  // Ensure this only gets run once.
  if ($finished) {
    return;
  }

  views_include('base');
  views_include('handlers');
  views_include('cache');
  views_include('plugins');
  _views_include_handlers();
  $finished = TRUE;
}

/**
 * Load default views files on behalf of modules.
 */
function views_include_default_views() {
  static $finished = FALSE;
  // Ensure this only gets run once.
  if ($finished) {
    return;
  }

  // Default views hooks may be in the normal handler file,
  // or in a separate views_default file at the discretion of
  // the module author.
  views_include_handlers();

  _views_include_default_views();
  $finished = TRUE;
}

// -----------------------------------------------------------------------
// Views handler functions

/**
 * Fetch a handler from the data cache.
 *
 * @param $table
 *   The name of the table this handler is from.
 * @param $field
 *   The name of the field this handler is from.
 * @param $key
 *   The type of handler. i.e, sort, field, argument, filter, relationship
 *
 * @return
 *   An instance of a handler object. May be views_handler_broken.
 */
function views_get_handler($table, $field, $key) {
  $data = views_fetch_data($table);
  if (isset($data[$field][$key])) {
    // Set up a default handler:
    if (empty($data[$field][$key]['handler'])) {
      $data[$field][$key]['handler'] = 'views_handler_' . $key;
    }
    return _views_prepare_handler($data[$field][$key], $data, $field);
  }
  // DEBUG -- identify missing handlers
  vpr("Missing handler: $table $field $key");
  $broken = array(
    'title' => t('Broken handler @table.@field', array('@table' => $table, '@field' => $field)),
    'handler' => 'views_handler_' . $key . '_broken',
    'table' => $table,
    'field' => $field,
  );
  return _views_create_handler($broken);
}

/**
 * Fetch Views' data from the cache
 */
function views_fetch_data($table = NULL) {
  views_include('cache');
  return _views_fetch_data($table);
}

// -----------------------------------------------------------------------
// Views plugin functions

/**
 * Fetch the plugin data from cache.
 */
function views_fetch_plugin_data($type = NULL, $plugin = NULL) {
  views_include('cache');
  return _views_fetch_plugin_data($type, $plugin);
}

/**
 * Get a handler for a plugin
 */
function views_get_plugin($type, $plugin) {
  $definition = views_fetch_plugin_data($type, $plugin);
  if (!empty($definition)) {
    return _views_create_handler($definition, $type);
  }
}

// -----------------------------------------------------------------------
// Views database functions

/**
 * Get a view from the default views defined by modules.
 *
 * Default views are cached per-language.  This function will rescan the
 * default_views hook if necessary.
 *
 * @param $view_name
 *   The name of the view to load.
 * @return
 *   A view object or NULL if it is not available.
 */
function &views_get_default_view($view_name) {
  $null = NULL;

  // Attempt to load individually cached view from cache.
  views_include('cache');
  $data = views_cache_get("views_default:{$view_name}", TRUE);
  if (isset($data->data) && is_object($data->data)) {
    return $data->data;
  }

  // Otherwise, allow entire cache to be rebuilt.
  $cache = views_discover_default_views();
  if (isset($cache[$view_name])) {
    return $cache[$view_name];
  }
  return $null;
}

/**
 * Create an empty view to work with.
 *
 * @return
 *   A fully formed, empty $view object. This object must be populated before
 *   it can be successfully saved.
 */
function views_new_view() {
  views_include('view');
  $view = new view();
  $view->vid = 'new';
  $view->add_display('default');

  return $view;
}

/**
 * Scan all modules for default views and rebuild the default views cache.
 *
 * @return An associative array of all known default views.
 */
function views_discover_default_views() {
  static $cache = array();

  if (empty($cache)) {
    views_include('cache');
    $cache = _views_discover_default_views();
  }
  return $cache;
}

/**
 * Return a list of all views and display IDs that have a particular
 * setting in their display's plugin settings.
 *
 * @return
 * @code
 * array(
 *   array($view, $display_id),
 *   array($view, $display_id),
 * );
 * @endcode
 */
function views_get_applicable_views($type) {
  // @todo: Use a smarter flagging system so that we don't have to
  // load every view for this.
  $result = array();
  $views = views_get_all_views();

  foreach ($views as $view) {
    // Skip disabled views.
    if (!empty($view->disabled)) {
      continue;
    }

    if (empty($view->display)) {
      // Skip this view as it is broken.
      vsm(t("Skipping broken view @view", array('@view' => $view->name)));
      continue;
    }

    // Loop on array keys because something seems to muck with $view->display
    // a bit in PHP4.
    foreach (array_keys($view->display) as $id) {
      $plugin = views_fetch_plugin_data('display', $view->display[$id]->display_plugin);
      if (!empty($plugin[$type])) {
        // This view uses hook menu. Clone it so that different handlers
        // don't trip over each other, and add it to the list.
        $v = $view->clone_view();
        if ($v->set_display($id)) {
          $result[] = array($v, $id);
        }
        // In PHP 4.4.7 and presumably earlier, if we do not unset $v
        // here, we will find that it actually overwrites references
        // possibly due to shallow copying issues.
        unset($v);
      }
    }
  }
  return $result;
}

/**
 * Return an array of all views as fully loaded $view objects.
 *
 * @param $reset
 *   If TRUE, reset the static cache forcing views to be reloaded.
 */
function views_get_all_views($reset = FALSE) {
  static $views = array();

  if (empty($views) || $reset) {
    $views = array();

    // First, get all applicable views.
    views_include('view');
    $views = view::load_views();

    // Get all default views.
    $status = variable_get('views_defaults', array());

    foreach (views_discover_default_views() as $view) {
      // Determine if default view is enabled or disabled.
      if (isset($status[$view->name])) {
        $view->disabled = $status[$view->name];
      }

      // If overridden, also say so.
      if (!empty($views[$view->name])) {
        $views[$view->name]->type = t('Overridden');
      }
      else {
        $view->type = t('Default');
        $views[$view->name] = $view;
      }
    }

  }
  return $views;
}

/**
 * Get a view from the database or from default views.
 *
 * This function is just a static wrapper around views::load(). This function
 * isn't called 'views_load()' primarily because it might get a view
 * from the default views which aren't technically loaded from the database.
 *
 * @param $name
 *   The name of the view.
 * @param $reset
 *   If TRUE, reset this entry in the load cache.
 * @return $view
 *   A reference to the $view object. Use $reset if you're sure you want
 *   a fresh one.
 */
function views_get_view($name, $reset = FALSE) {
  views_include('view');
  $view = view::load($name, $reset);
  $default_view = views_get_default_view($name);

  if (empty($view) && empty($default_view)) {
    return;
  }
  elseif (empty($view) && !empty($default_view)) {
    $status = variable_get('views_defaults', array());
    if (isset($status[$default_view->name])) {
      $default_view->disabled = $status[$default_view->name];
    }
    $default_view->type = t('Default');
    return $default_view->clone_view();
  }
  elseif (!empty($view) && !empty($default_view)) {
    $view->type = t('Overridden');
  }

  return $view->clone_view();
}

// ------------------------------------------------------------------
// Views debug helper functions

/**
 * Provide debug output for Views. This relies on devel.module
 */
function views_debug($message) {
  if (module_exists('devel') && variable_get('views_devel_output', FALSE) && user_access('access devel information')) {
    if (is_string($message)) {
      $output = $message;
    }
    else {
      $output = var_export($message, TRUE);
    }
    if (variable_get('views_devel_region', 'footer') != 'watchdog') {
      drupal_set_content(variable_get('views_devel_region', 'footer'), '<pre>' . $output . '</pre>');
    }
    else {
      watchdog('views_logging', '<pre>' . $output . '</pre>');
    }
  }
}

/**
 * Shortcut to views_debug()
 */
function vpr($message) {
  views_debug($message);
}

/**
 * Debug messages
 */
function vsm($message) {
  if (module_exists('devel')) {
    dsm($message);
  }
}

function views_trace() {
  $message = '';
  foreach (debug_backtrace() as $item) {
    if (!empty($item['file']) && !in_array($item['function'], array('vsm_trace', 'vpr_trace', 'views_trace'))) {
      $message .= basename($item['file']) . ": " . (empty($item['class']) ? '' : ($item['class'] . '->')) . "$item[function] line $item[line]" . "\n";
    }
  }
  return $message;
}

function vsm_trace() {
  vsm(views_trace());
}

function vpr_trace() {
  dpr(views_trace());
}

// ------------------------------------------------------------------
// Exposed widgets form

/**
 * Form builder for the exposed widgets form.
 *
 * Be sure that $view and $display are references.
 */
function views_exposed_form(&$form_state) {
  // Don't show the form when batch operations are in progress.
  $batch =& batch_get();
  if (!empty($batch)) {
    return array(
      // Set the theme callback to be nothing to avoid errors in template_preprocess_views_exposed_form().
      '#theme' => '',
    );
  }

  // Make sure that we validate because this form might be submitted
  // multiple times per page.
  $form_state['must_validate'] = TRUE;
  $view = &$form_state['view'];
  $display = &$form_state['display'];

  $form_state['input'] = $view->get_exposed_input();

  // Let form plugins know this is for exposed widgets.
  $form_state['exposed'] = TRUE;
  // Check if the form was already created
  if ($cache = views_exposed_form_cache($view->name, $view->current_display)) {
    return $cache;
  }

  $form['#info'] = array();

  if (!variable_get('clean_url', FALSE)) {
    $form['q'] = array(
      '#type' => 'hidden',
      '#value' => $view->get_url(),
    );
  }

  // Go through each filter and let it generate its info.
  foreach ($view->filter as $id => $filter) {
    $view->filter[$id]->exposed_form($form, $form_state);
    if ($info = $view->filter[$id]->exposed_info()) {
      $form['#info']['filter-' . $id] = $info;
    }
  }

  // @todo deal with exposed sorts

  $form['submit'] = array(
    '#name' => '', // prevent from showing up in $_GET.
    '#type' => 'submit',
    '#value' => t('Apply'),
    '#id' => form_clean_id('edit-submit-' . $view->name),
  );

  $form['#action'] = url($view->get_url());
  $form['#theme'] = views_theme_functions('views_exposed_form', $view, $display);
  $form['#id'] = views_css_safe('views_exposed_form-' . check_plain($view->name) . '-' . check_plain($display->id));
//  $form['#attributes']['class'] = array('views-exposed-form');

  // If using AJAX, we need the form plugin.
  if ($view->use_ajax) {
    drupal_add_js('misc/jquery.form.js');
  }
  views_add_js('dependent');

  // Save the form
  views_exposed_form_cache($view->name, $view->current_display, $form);

  return $form;
}

/**
 * Validate handler for exposed filters
 */
function views_exposed_form_validate(&$form, &$form_state) {
  foreach (array('field', 'filter') as $type) {
    $handlers = &$form_state['view']->$type;
    foreach ($handlers as $key => $handler) {
      $handlers[$key]->exposed_validate($form, $form_state);
    }
  }
}

/**
 * Submit handler for exposed filters
 */
function views_exposed_form_submit(&$form, &$form_state) {
  foreach (array('field', 'filter') as $type) {
    $handlers = &$form_state['view']->$type;
    foreach ($handlers as $key => $info) {
      $handlers[$key]->exposed_submit($form, $form_state);
    }
  }
  $form_state['view']->exposed_data = $form_state['values'];
  $form_state['view']->exposed_raw_input = array();

  foreach ($form_state['values'] as $key => $value) {
    if (!in_array($key, array('q', 'submit', 'form_build_id', 'form_id', 'form_token', ''))) {
      $form_state['view']->exposed_raw_input[$key] = $value;
    }
  }
}

/**
 * Save the Views exposed form for later use.
 *
 * @param $views_name
 *   String. The views name.
 * @param $display_name
 *   String. The current view display name.
 * @param $form_output
 *   Array (optional). The form structure. Only needed when inserting the value.
 * @return
 *   Array. The form structure, if any. Otherwise, return FALSE.
 */
function views_exposed_form_cache($views_name, $display_name, $form_output = NULL) {
  static $views_exposed;

  // Save the form output
  if (!empty($form_output)) {
    $views_exposed[$views_name][$display_name] = $form_output;
    return;
  }

  // Return the form output, if any
  return empty($views_exposed[$views_name][$display_name]) ? FALSE : $views_exposed[$views_name][$display_name];
}

// ------------------------------------------------------------------
// Misc helpers

/**
 * Build a list of theme function names for use most everywhere.
 */
function views_theme_functions($hook, $view, $display = NULL) {
  require_once './' . drupal_get_path('module', 'views') . "/theme/theme.inc";
  return _views_theme_functions($hook, $view, $display);
}

/**
 * Views' replacement for drupal_get_form so that we can do more with
 * less.
 *
 * Items that can be set on the form_state include:
 * - input: The source of input. If unset this will be $_POST.
 * - no_redirect: Absolutely do not redirect the form even if instructed
 *   to do so.
 * - rerender: If no_redirect is set and the form was successfully submitted,
 *   rerender the form. Otherwise it will just return.
 *
 */
function drupal_build_form($form_id, &$form_state) {
  views_include('form');
  return _drupal_build_form($form_id, $form_state);
}

/**
 * Substitute current time; this works with cached queries.
 */
function views_views_query_substitutions($view) {
  global $language;
  return array(
    '***CURRENT_VERSION***' => VERSION,
    '***CURRENT_TIME***' => time(),
    '***CURRENT_LANGUAGE***' => $language->language,
    '***DEFAULT_LANGUAGE***' => language_default('language'),
    '***NO_LANGUAGE***' => '',
  );
}

/**
 * Embed a view using a PHP snippet.
 *
 * This function is meant to be called from PHP snippets, should one wish to
 * embed a view in a node or something. It's meant to provide the simplest
 * solution and doesn't really offer a lot of options, but breaking the function
 * apart is pretty easy, and this provides a worthwhile guide to doing so.
 *
 * Note that this function does NOT display the title of the view. If you want
 * to do that, you will need to do what this function does manually, by
 * loading the view, getting the preview and then getting $view->get_title().
 *
 * @param $name
 *   The name of the view to embed.
 * @param $display_id
 *   The display id to embed. If unsure, use 'default', as it will always be
 *   valid. But things like 'page' or 'block' should work here.
 * @param ...
 *   Any additional parameters will be passed as arguments.
 */
function views_embed_view($name, $display_id = 'default') {
  $args = func_get_args();
  array_shift($args); // remove $name
  if (count($args)) {
    array_shift($args); // remove $display_id
  }

  $view = views_get_view($name);
  if (!$view || !$view->access($display_id)) {
    return;
  }

  return $view->preview($display_id, $args);
}

/**
* Get the result of a view.
*
* @param string $name
*      The name of the view to retrieve the data from.
* @param string $display_id
*      The display id. On the edit page for the view in question, you'll find
*      a list of displays at the left side of the control area. "Defaults"
*      will be at the top of that list. Hover your cursor over the name of the
*      display you want to use. An URL will appear in the status bar of your
*      browser. This is usually at the bottom of the window, in the chrome.
*      Everything after #views-tab- is the display ID, e.g. page_1.
 * @param ...
 *   Any additional parameters will be passed as arguments.
* @return
*      array
*          An array containing an object for each view item.
*/
function views_get_view_result($name, $display_id = NULL) {
  $args = func_get_args();
  array_shift($args); // remove $name
  if (count($args)) {
    array_shift($args); // remove $display_id
  }

  $view = views_get_view($name);
  if (is_object($view)) {
    if (is_array($args)) {
      $view->set_arguments($args);
    }
    if (is_string($display_id)) {
      $view->set_display($display_id);
    }
    else {
      $view->init_display();
    }
    $view->pre_execute();
    $view->execute();
    return $view->result;
  }
  else {
    return array();
  }
}

/**
 * Export a field.
 */
function views_var_export($var, $prefix = '', $init = TRUE) {
  if (is_array($var)) {
    if (empty($var)) {
      $output = 'array()';
    }
    else {
      $output = "array(\n";
      foreach ($var as $key => $value) {
        $output .= "  '$key' => " . views_var_export($value, '  ', FALSE) . ",\n";
      }
      $output .= ')';
    }
  }
  else if (is_bool($var)) {
    $output = $var ? 'TRUE' : 'FALSE';
  }
  else if (is_string($var) && strpos($var, "\n") !== FALSE) {
    // Replace line breaks in strings with a token for replacement
    // at the very end. This protects multi-line strings from
    // unintentional indentation.
    $var = str_replace("\n", "***BREAK***", $var);
    $output = var_export($var, TRUE);
  }
  else {
    $output = var_export($var, TRUE);
  }

  if ($prefix) {
    $output = str_replace("\n", "\n$prefix", $output);
  }

  if ($init) {
    $output = str_replace("***BREAK***", "\n", $output);
  }

  return $output;
}

/**
 * Prepare the specified string for use as a CSS identifier.
 */
function views_css_safe($string) {
  return str_replace('_', '-', $string);
}

/**
 * Implementation of hook_views_exportables().
 */
function views_views_exportables($op = 'list', $views = NULL, $name = 'foo') {
  $all_views = views_get_all_views();
  if ($op == 'list') {

    foreach ($all_views as $name => $view) {
      // in list, $views is a list of tags.
      if (empty($views) || in_array($view->tag, $views)) {
        $return[$name] = array(
          'name' => check_plain($name),
          'desc' => check_plain($view->description),
          'tag' => check_plain($view->tag)
        );
      }
    }
    return $return;
  }

  if ($op == 'export') {
    $code = "/**\n";
    $code .= " * Implementation of hook_views_default_views().\n";
    $code .= " */\n";
    $code .= "function " . $name . "_views_default_views() {\n";
    foreach ($views as $view => $truth) {
      $code .= "  /*\n";
      $code .= "   * View ". var_export($all_views[$view]->name, TRUE) ."\n";
      $code .= "   */\n";
      $code .= $all_views[$view]->export('  ');
      $code .= '  $views[$view->name] = $view;' . "\n\n";
    }
    $code .= "  return \$views;\n";
    $code .= "}\n";

    return $code;
  }
}

/**
 * Microtime helper function to return a float time value (php4 & php5 safe).
 */
function views_microtime() {
  list($usec, $sec) = explode(' ', microtime());
  return (float)$sec + (float)$usec;
}

/**
 * Trim the field down to the specified length.
 *
 * @param $alter
 *   - max_length: Maximum lenght of the string, the rest gets truncated.
 *   - word_boundary: Trim only on a word boundary.
 *   - ellipsis: Trim only on a word boundary.
 *   - html: Take sure that the html is correct.
 */
function views_trim_text($alter, $value) {
  if (drupal_strlen($value) > $alter['max_length']) {
    $value = drupal_substr($value, 0, $alter['max_length']);
    // TODO: replace this with cleanstring of ctools
    if (!empty($alter['word_boundary'])) {
      $regex = "(.*)\b.+";
      if (function_exists('mb_ereg')) {
        mb_regex_encoding('UTF-8');
        $found = mb_ereg($regex, $value, $matches);
      }
      else {
        $found = preg_match("/$regex/us", $value, $matches);
      }
      if ($found) {
        $value = $matches[1];
      }
    }
    // Remove scraps of HTML entities from the end of a strings
    $value = rtrim(preg_replace('/(?:<(?!.+>)|&(?!.+;)).*$/us', '', $value));

    if (!empty($alter['ellipsis'])) {
      $value .= '...';
    }
  }
  if (!empty($alter['html'])) {
    $value = _filter_htmlcorrector($value);
  }

  return $value;
}

Other Drupal examples (source code examples)

Here is a short list of links related to this Drupal views.module source code file:

new blog posts

"Drupal" is a registered trademark of Dries Buytaert.

my drupal tutorials and examples  

Copyright 1998-2016 Alvin Alexander, alvinalexander.com
All Rights Reserved.

Beginning in 2016, a portion of the proceeds from pages under the '/drupal-code-examples/' URI will be donated to charity.