spatial-navigation/lib/Navigation.js

A javascript-based implementation of Spatial Navigation.

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _EventAggregator = require('./EventAggregator');

var _EventAggregator2 = _interopRequireDefault(_EventAggregator);

var _constants = require('./util/constants');

var _Container = require('./Container');

var _Container2 = _interopRequireDefault(_Container);

var _ContainerNavigation = require('./ContainerNavigation');

var _ContainerNavigation2 = _interopRequireDefault(_ContainerNavigation);

var _ElementNavigation = require('./ElementNavigation');

var _ElementNavigation2 = _interopRequireDefault(_ElementNavigation);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var Navigation = function () {
  function Navigation() {
    _classCallCheck(this, Navigation);

    /**
     * @type {null|Element}
     */
    this.focusedElement = null;

    this.bindListeners();
  }

  _createClass(Navigation, [{
    key: 'bindListeners',
    value: function bindListeners() {
      _EventAggregator2.default.subscribe(_constants.EVENT_PREFIX + 'navigate', this.navigate.bind(this));
      _EventAggregator2.default.subscribe(_constants.EVENT_PREFIX + 'focusElement', this.setFocusedElement.bind(this));
    }
  }, {
    key: 'navigate',
    value: function navigate(actionName) {
      if (!~['up', 'down', 'left', 'right'].indexOf(actionName)) {
        return;
      }

      var instanceToFocus = this.getInstanceToFocus(actionName);

      if (!instanceToFocus) {
        return;
      }

      this.focusInstance(instanceToFocus);
    }
  }, {
    key: 'getInstanceToFocus',
    value: function getInstanceToFocus(direction) {
      var instance = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : this.focusedElement;

      if (!Boolean(instance)) {
        return null;
      }

      var instanceToFocus = _ElementNavigation2.default.getToNavigate(instance, direction);

      // if there is no Element to navigate in passed direction
      if (!instanceToFocus) {
        // if parent of Element is Container
        if (instance.parent.constructor.name === 'Container') {
          instanceToFocus = _ContainerNavigation2.default.getToNavigate(instance.parent, direction);
        }
        // if parent of Element is Element
        else {
            return this.getInstanceToFocus(direction, instance.parent);
          }
      }

      return instanceToFocus;
    }
  }, {
    key: 'focusInstance',
    value: function focusInstance(instance) {
      var prevFocusedElement = this.focusedElement;

      instance.focus();

      // dispatch event of collection focused element belongs to
      if (instance.parent && instance.parent.collection) {
        instance.parent.collection.eventAggregator.dispatchEvent('onNavigate');
      }

      // dispatch event of parent of collection focused element belongs to
      if (prevFocusedElement && instance.parent && prevFocusedElement.parent && instance.parent != prevFocusedElement.parent && instance.parent.parent && instance.parent.parent.collection) {
        instance.parent.parent.collection.eventAggregator.dispatchEvent('onNavigate');
      }
    }
  }, {
    key: 'setFocusedElement',
    value: function setFocusedElement(element) {
      this.focusedElement = element;
    }
  }]);

  return Navigation;
}();

exports.default = new Navigation();
module.exports = exports['default'];