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                <base href="">
<script src="../webcomponentsjs/webcomponents-lite.js"></script>

<link rel="import" href="../iron-demo-helpers/url-bar.html">
<link rel="import" href="../iron-pages/iron-pages.html">

<link rel="import" href="app-location.html">
<link rel="import" href="app-route.html">

<link rel="import" href="demo/youtube-demo/youtube-search.html">
<link rel="import" href="demo/youtube-demo/youtube-toolbar.html">
<link rel="import" href="demo/youtube-demo/video-viewer.html">
<link rel="import" href="demo/youtube-demo/search-results.html">



<dom-module id="app-router-demo">
      :host {
        display: block;
        position: relative;
        height: 100vh;
        @apply --paper-font-common-base;
      :host([video-page-active]) {
        overflow: hidden;
      :host([video-page-active]) iron-pages {
        transform: translateY(-170px);
      iron-pages {
        transition: transform 0.3s;

    <!-- app-location binds with the URL and produces a route for app-route elements to consume. Since this demo needs to run without server cooperation (e.g. with polyserve, in the elements catalog, etc) we'll use the hash portion of the URL for our route paths. -->
    <app-location route="{{route}}" use-hash-as-path></app-location>

    <!-- app-routes parse route paths based on the their `pattern`. Parameters are extracted into the `data` object. The rest of the path that comes after the `pattern` is put into the `tail` object, which can be passed to the `route` property of downstream app-routes. -->
    <app-route route="{{route}}" pattern="/:page" data="{{data}}"></app-route>
    <app-route route="{{route}}" pattern="/search" tail="{{searchTail}}"></app-route>
    <app-route route="{{route}}" pattern="/video" tail="{{videoTail}}" active="{{videoPageActive}}"></app-route>

    <youtube-toolbar collapsed$="{{videoPageActive}}">
      <!-- The youtube-search has a app-route that consumes the tail of another route (`searchTail`) -->

    <iron-pages attr-for-selected="id" selected="{{}}">
      <search-results id="search" items="{{videos}}"></search-results>

      <!-- The video-viewer has a app-route that consumes the tail of another route -->
      <video-viewer id="video" route="{{videoTail}}"></video-viewer>


    window.addEventListener("WebComponentsReady", function() {
        is: "app-router-demo",
        properties: {
          route: {
            type: Object
          videoData: {
            type: Object,
            observer: "_videoDataChanged"
          videoPageActive: {
            type: Boolean,
            reflectToAttribute: true,
            observer: "_videoPageActiveChanged"
          searchTail: {
            type: Object,
            notify: true
          videoTail: {
            type: Object,
            notify: true
          newCategory: {
            type: String
          videos: {
            type: Array,
            value: function() {
              return [];
          data: {
            type: Object,
            value: function() {
              return {
                page: "/search/"
        attached: function() {
          // If we do not have an initial URL, we redirect to /search
          if (!this.route || !this.route.path) {
            this.set("route.path", "/search/");
        _videoDataChanged: function(data) {
          var allVideos = [];
          var that = this;
          data.items.forEach(function(videoItem) {
            var youtubeVideo = {
              title: videoItem.snippet.title,
              thumbnail: videoItem.snippet.thumbnails.high.url
          this.set("videos", allVideos);
        _videoPageActiveChanged: function(videoPageActive, previousValue) {
          // change color of page on page change
          var newColor;
          if (videoPageActive) {
            // black
            newColor = 0;
          } else {
            // white
            newColor = 255;
            "rgb(" + newColor + "," + newColor + "," + newColor + ")";
          // on first load, set the color then allow color transition animations
          if (previousValue === undefined) {
   = "background-color .2s linear";


                body {
  margin: 0;
  padding: 0;
url-bar {
  background-color: white;