@oat-sa/tao-test-runner-qti/src/plugins/navigation/warnBeforeLeaving.js

TAO Test Runner QTI implementation

/**
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; under version 2
 * of the License (non-upgradable).
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (c) 2017 (original work) Open Assessment Technologies SA ;
 */

/**
 * Warn the test taker before closing the browser window
 *
 * @author Bertrand Chevrier <bertrand@taotesting.com>
 */
import __ from 'i18n';
import pluginFactory from 'taoTests/runner/plugin';

/**
 * There's only a few chance to have this message displayed.
 * Most browsers doesn't support custom message anymore.
 * See https://www.chromestatus.com/feature/5349061406228480
 */
var warnMessage = __('Please confirm you want to leave the test.');

/**
 * The beforeunload listener
 * @param {Event} e
 * @returns {String} the custom message (for some browser, just need to be a string)
 */
var warnListener = function warnListener(e) {
    e.returnValue = warnMessage;
    return warnMessage;
};

/**
 * Plugin factory
 * @returns {Object}
 */
export default pluginFactory({
    /**
     * Plugin name
     * @type {String}
     */
    name: 'warnBeforeLeaving',

    /**
     * Initialize plugin (called during runner's initialization)
     */
    init: function init() {
        this.enable();
    },

    /**
     * Destroy plugin (called during runner's destruction)
     */
    destroy: function destroy() {
        this.disable();
    },

    /**
     * Enables the warning
     */
    enable: function enable() {
        window.addEventListener('beforeunload', warnListener);
    },

    /**
     * Disables the warning
     */
    disable: function disable() {
        window.removeEventListener('beforeunload', warnListener);
    }
});