Show:
                            /**
                            Provides the implementation of view transitions for `Y.App.Transitions` in
                            browsers which support native CSS3 transitions.
                            
                            @module app
                            @submodule app-transitions-native
                            @since 3.5.0
                            **/
                            
                            var AppTransitions = Y.App.Transitions;
                            
                            /**
                            Provides the implementation of view transitions for `Y.App.Transitions` in
                            browsers which support native CSS3 transitions.
                            
                            When this module is used, `Y.App.TransitionsNative` will automatically mix
                            itself in to `Y.App`.
                            
                            @class App.TransitionsNative
                            @extensionfor App
                            @since 3.5.0
                            **/
                            function AppTransitionsNative() {}
                            
                            AppTransitionsNative.prototype = {
                                // -- Protected Properties -------------------------------------------------
                            
                                /**
                                Whether this app is currently transitioning its `activeView`.
                            
                                @property _transitioning
                                @type Boolean
                                @default false
                                @protected
                                @since 3.5.0
                                **/
                            
                                /**
                                A queue that holds pending calls to this app's `_uiTransitionActiveView()`
                                method.
                            
                                @property _viewTransitionQueue
                                @type Array
                                @default []
                                @protected
                                @since 3.5.0
                                **/
                            
                                // -- Lifecycle Methods ----------------------------------------------------
                            
                                initializer: function () {
                                    this._transitioning       = false;
                                    this._viewTransitionQueue = [];
                            
                                    // TODO: Consider the AOP approach that `Plugin.WidgetAnim` uses.
                                    Y.Do.before(this._queueActiveView, this, '_uiSetActiveView');
                                },
                            
                                // -- Protected Methods ----------------------------------------------------
                            
                                /**
                                Dequeues any pending calls to `_uiTransitionActiveView()`.
                            
                                **Note:** When there is more than one queued transition, only the most
                                recent `activeView` change will be visually transitioned, while the others
                                will have their `transition` option overridden to `false`.
                            
                                @method _dequeueActiveView
                                @protected
                                @since 3.5.0
                                **/
                                _dequeueActiveView: function () {
                                    var queue      = this._viewTransitionQueue,
                                        transition = queue.shift(),
                                        options;
                            
                                    if (transition) {
                                        // When items are still left in the queue, override the transition
                                        // so it does not run.
                                        if (queue.length) {
                                            // Overrides `transition` option and splices in the new options.
                                            options = Y.merge(transition[2], {transition: false});
                                            transition.splice(2, 1, options);
                                        }
                            
                                        this._uiTransitionActiveView.apply(this, transition);
                                    }
                                },
                            
                                /**
                                Returns an object containing a named fx for both `viewIn` and `viewOut`
                                based on the relationship between the specified `newView` and `oldView`.
                            
                                @method _getFx
                                @param {View} newView The view being transitioned-in.
                                @param {View} oldView The view being transitioned-out.
                                @param {String} [transition] The preferred transition to use.
                                @return {Object} An object containing a named fx for both `viewIn` and
                                    `viewOut`.
                                @protected
                                @since 3.5.0
                                **/
                                _getFx: function (newView, oldView, transition) {
                                    var fx          = AppTransitions.FX,
                                        transitions = this.get('transitions');
                            
                                    if (transition === false || !transitions) {
                                        return null;
                                    }
                            
                                    if (transition) {
                                        return fx[transition];
                                    }
                            
                                    if (this._isChildView(newView, oldView)) {
                                        return fx[transitions.toChild];
                                    }
                            
                                    if (this._isParentView(newView, oldView)) {
                                        return fx[transitions.toParent];
                                    }
                            
                                    return fx[transitions.navigate];
                                },
                            
                                /**
                                Queues calls to `_uiTransitionActiveView()` to make sure a currently running
                                transition isn't interrupted.
                            
                                **Note:** This method prevents the default `_uiSetActiveView()` method from
                                running.
                            
                                @method _queueActiveView
                                @protected
                                @since 3.5.0
                                **/
                                _queueActiveView: function () {
                                    var args = Y.Array(arguments, 0, true);
                            
                                    this._viewTransitionQueue.push(args);
                            
                                    if (!this._transitioning) {
                                        this._dequeueActiveView();
                                    }
                            
                                    return new Y.Do.Prevent();
                                },
                            
                                /**
                                Performs the actual change of this app's `activeView` by visually
                                transitioning between the `newView` and `oldView` using any specified
                                `options`.
                            
                                The `newView` is attached to the app by rendering it to the `viewContainer`,
                                and making this app a bubble target of its events.
                            
                                The `oldView` is detached from the app by removing it from the
                                `viewContainer`, and removing this app as a bubble target for its events.
                                The `oldView` will either be preserved or properly destroyed.
                            
                                **Note:** This method overrides `_uiSetActiveView()` and provides all of its
                                functionality plus supports visual transitions. Also, the `activeView`
                                attribute is read-only and can be changed by calling the `showView()`
                                method.
                            
                                @method _uiTransitionActiveView
                                @param {View} newView The View which is now this app's `activeView`.
                                @param {View} [oldView] The View which was this app's `activeView`.
                                @param {Object} [options] Optional object containing any of the following
                                    properties:
                                  @param {Function} [options.callback] Optional callback function to call
                                    after new `activeView` is ready to use, the function will be passed:
                                      @param {View} options.callback.view A reference to the new
                                        `activeView`.
                                  @param {Boolean} [options.prepend=false] Whether the `view` should be
                                    prepended instead of appended to the `viewContainer`.
                                  @param {Boolean} [options.render] Whether the `view` should be rendered.
                                    **Note:** If no value is specified, a view instance will only be
                                    rendered if it's newly created by this method.
                                  @param {Boolean|String} [options.transition] Optional transition override.
                                    A transition can be specified which will override the default, or
                                    `false` for no transition.
                                  @param {Boolean} [options.update=false] Whether an existing view should
                                    have its attributes updated by passing the `config` object to its
                                    `setAttrs()` method. **Note:** This option does not have an effect if
                                    the `view` instance is created as a result of calling this method.
                                @protected
                                @since 3.5.0
                                **/
                                _uiTransitionActiveView: function (newView, oldView, options) {
                                    options || (options = {});
                            
                                    var callback = options.callback,
                                        container, transitioning, isChild, isParent, prepend,
                                        fx, fxConfig, transitions;
                            
                                    // Quits early when to new and old views are the same.
                                    if (newView === oldView) {
                                        callback && callback.call(this, newView);
                            
                                        this._transitioning = false;
                                        return this._dequeueActiveView();
                                    }
                            
                                    fx       = this._getFx(newView, oldView, options.transition);
                                    isChild  = this._isChildView(newView, oldView);
                                    isParent = !isChild && this._isParentView(newView, oldView);
                                    prepend  = !!options.prepend || isParent;
                            
                                    // Preforms simply attach/detach of the new and old view respectively
                                    // when there's no transition to perform.
                                    if (!fx) {
                                        this._attachView(newView, prepend);
                                        this._detachView(oldView);
                                        callback && callback.call(this, newView);
                            
                                        this._transitioning = false;
                                        return this._dequeueActiveView();
                                    }
                            
                                    this._transitioning = true;
                            
                                    container     = this.get('container');
                                    transitioning = Y.App.CLASS_NAMES.transitioning;
                            
                                    container.addClass(transitioning);
                            
                                    this._attachView(newView, prepend);
                            
                                    // Called when view transitions completed, if none were added this will
                                    // run right away.
                                    function complete() {
                                        this._detachView(oldView);
                                        container.removeClass(transitioning);
                                        callback && callback.call(this, newView);
                            
                                        this._transitioning = false;
                                        return this._dequeueActiveView();
                                    }
                            
                                    // Setup a new stack to run the view transitions in parallel.
                                    transitions = new Y.Parallel({context: this});
                                    fxConfig    = {
                                        crossView: !!oldView && !!newView,
                                        prepended: prepend
                                    };
                            
                                    // Transition the new view first to prevent a gap when sliding.
                                    if (newView && fx.viewIn) {
                                        newView.get('container')
                                            .transition(fx.viewIn, fxConfig, transitions.add());
                                    }
                            
                                    if (oldView && fx.viewOut) {
                                        oldView.get('container')
                                            .transition(fx.viewOut, fxConfig, transitions.add());
                                    }
                            
                                    transitions.done(complete);
                                }
                            };
                            
                            // -- Transition fx ------------------------------------------------------------
                            Y.mix(Y.Transition.fx, {
                                'app:fadeIn': {
                                    opacity : 1,
                                    duration: 0.3,
                            
                                    on: {
                                        start: function (data) {
                                            var styles = {opacity: 0},
                                                config = data.config;
                            
                                            if (config.crossView && !config.prepended) {
                                                styles.transform = 'translateX(-100%)';
                                            }
                            
                                            this.setStyles(styles);
                                        },
                            
                                        end: function () {
                                            this.setStyle('transform', 'translateX(0)');
                                        }
                                    }
                                },
                            
                                'app:fadeOut': {
                                    opacity : 0,
                                    duration: 0.3,
                            
                                    on: {
                                        start: function (data) {
                                            var styles = {opacity: 1},
                                                config = data.config;
                            
                                            if (config.crossView && config.prepended) {
                                                styles.transform = 'translateX(-100%)';
                                            }
                            
                                            this.setStyles(styles);
                                        },
                            
                                        end: function () {
                                            this.setStyle('transform', 'translateX(0)');
                                        }
                                    }
                                },
                            
                                'app:slideLeft': {
                                    duration : 0.3,
                                    transform: 'translateX(-100%)',
                            
                                    on: {
                                        start: function () {
                                            this.setStyles({
                                                opacity  : 1,
                                                transform: 'translateX(0%)'
                                            });
                                        },
                            
                                        end: function () {
                                            this.setStyle('transform', 'translateX(0)');
                                        }
                                    }
                                },
                            
                                'app:slideRight': {
                                    duration : 0.3,
                                    transform: 'translateX(0)',
                            
                                    on: {
                                        start: function () {
                                            this.setStyles({
                                                opacity  : 1,
                                                transform: 'translateX(-100%)'
                                            });
                                        },
                            
                                        end: function () {
                                            this.setStyle('transform', 'translateX(0)');
                                        }
                                    }
                                }
                            });
                            
                            // -- Namespacae ---------------------------------------------------------------
                            Y.App.TransitionsNative = AppTransitionsNative;
                            Y.Base.mix(Y.App, [AppTransitionsNative]);