context_exists.inc

<?php


/**
 * @file
 * Plugin to provide access control/visibility based on existence of a specified context.
 */
$plugin = array(
    'title' => t("Context exists"),
    'description' => t('Control access by whether or not a context exists and contains data.'),
    'callback' => 'ctools_context_exists_ctools_access_check',
    'settings form' => 'ctools_context_exists_ctools_access_settings',
    'summary' => 'ctools_context_exists_ctools_access_summary',
    'required context' => new ctools_context_required(t('Context'), 'any', TRUE),
    'defaults' => array(
        'exists' => TRUE,
    ),
);

/**
 * Settings form.
 */
function ctools_context_exists_ctools_access_settings($form, &$form_state, $conf) {
    $form['settings']['exists'] = array(
        '#type' => 'radios',
        '#description' => t("Check to see if the context exists (contains data) or does not exist (contains no data). For example, if a context is optional and the path does not contain an argument for that context, it will not exist."),
        '#options' => array(
            TRUE => t('Exists'),
            FALSE => t("Doesn't exist"),
        ),
        '#default_value' => $conf['exists'],
    );
    return $form;
}

/**
 * Check for access.
 */
function ctools_context_exists_ctools_access_check($conf, $context) {
    // Xor returns false if the two bools are the same, and true if they are not.
    // i.e, if we asked for context_exists and it does, return true.
    // If we asked for context does not exist and it does, return false.
    return empty($context->data) xor !empty($conf['exists']);
}

/**
 * Provide a summary description based upon the specified context.
 */
function ctools_context_exists_ctools_access_summary($conf, $context) {
    if (!empty($conf['exists'])) {
        return t('@identifier exists', array(
            '@identifier' => $context->identifier,
        ));
    }
    else {
        return t('@identifier does not exist', array(
            '@identifier' => $context->identifier,
        ));
    }
}