preprocess_views.php

<?php
/**
 * Override variables used in views template for fields.
 *
 * @see views-view-fields.tpl.php
 */
function theme_preprocess_views_view_fields(&$vars) {
  // Until http://drupal.org/node/939462 lands for Drupal 7 we need to specify
  // the specific preprocess functions ourself.
  $preprocess_names = array();
  $preprocess_names[] = sprintf('%s__%s', __FUNCTION__, $vars['view']->name);
  $preprocess_names[] = sprintf('%s__%s__%s', __FUNCTION__, $vars['view']->name, $vars['view']->current_display);
  // Call more specific preprocess functions.
  foreach ($preprocess_names as $function) {
    if (function_exists($function)) {
      call_user_func_array($function, array(&$vars));
    }
  }
}

/**
 * Override variables used in views template for a single field.
 *
 * @see views-view-field.tpl.php
 */
function theme_preprocess_views_view_field(&$vars) {
  // Until http://drupal.org/node/939462 lands for Drupal 7 we need to specify
  // the specific preprocess functions ourself.
  $preprocess_names = array();
  $preprocess_names[] = sprintf('%s__%s', __FUNCTION__, $vars['view']->name);
  $preprocess_names[] = sprintf('%s__%s__%s', __FUNCTION__, $vars['view']->name, $vars['view']->current_display);
  $preprocess_names[] = sprintf('%s__%s__field_%s', __FUNCTION__, $vars['view']->name, $vars['field']->options['id']);
  $preprocess_names[] = sprintf('%s__%s__%s__%s', __FUNCTION__, $vars['view']->name, $vars['view']->current_display, $vars['field']->options['id']);
  // Call more specific preprocess functions.
  foreach ($preprocess_names as $function) {
    if (function_exists($function)) {
      call_user_func_array($function, array(&$vars));
    }
  }
}