Wi-Fi List: Keep focus on active row when update is received.

This fixes a long standing bug where the focus moved back up
to the first network when an update to the list of available networks
came in.

Bug: 720274
Change-Id: Iee036aa649a74eef1b1743317a07b35061e08d3c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2480712Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Jon Mann <jonmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#819297}

ui/webui/resources/cr_components/chromeos/network/BUILD.gn

@@ -205,6 +205,7 @@ js_library("network_list") {
   deps = [
     ":network_list_types",
     "//ui/webui/resources/cr_elements:cr_scrollable_behavior",
+    "//ui/webui/resources/js:list_property_update_behavior",
   ]
 }
 
@@ -214,6 +215,7 @@ js_library("network_list_item") {
     ":network_list_types",
     "//ui/webui/resources/js:assert",
     "//ui/webui/resources/js:i18n_behavior",
+    "//ui/webui/resources/js/cr/ui:focus_row_behavior",
   ]
 }
 
@@ -277,6 +279,10 @@ js_type_check("closure_compile_module") {
     ":network_siminfo.m",
     ":onc_mojo.m",
   ]
+
+  # closure_flags = default_closure_args + [
+  #                   "js_module_root=../../ui/webui/resources/js/",
+  #                   "js_module_root=./gen/ui/webui/resources/js/"]
 }
 
 js_library("mojo_interface_provider.m") {
@@ -437,6 +443,7 @@ js_library("network_list.m") {
     "//third_party/polymer/v3_0/components-chromium/iron-list:iron-list",
     "//third_party/polymer/v3_0/components-chromium/polymer:polymer_bundled",
     "//ui/webui/resources/cr_elements:cr_scrollable_behavior.m",
+    "//ui/webui/resources/js:list_property_update_behavior.m",
   ]
   extra_deps = [ ":network_list_module" ]
 }
@@ -446,6 +453,7 @@ js_library("network_list_item.m") {
   deps = [
     ":network_list_types.m",
     "//third_party/polymer/v3_0/components-chromium/polymer:polymer_bundled",
+    "//ui/webui/resources/js/cr/ui:focus_row_behavior.m",
   ]
   extra_deps = [ ":network_list_item_module" ]
 }

ui/webui/resources/cr_components/chromeos/network/network_list.html

@@ -6,6 +6,7 @@
 <link rel="import" href="../../../cr_elements/shared_style_css.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-flex-layout/iron-flex-layout-classes.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-list/iron-list.html">
+<link rel="import" href="../../../html/list_property_update_behavior.html">
 
 <dom-module id="network-list">
   <template>
@@ -36,13 +37,18 @@
     </style>
     <div id="container" class="layout vertical flex" scrollable
         no-bottom-scroll-border$="[[noBottomScrollBorder]]">
-      <iron-list id="networkList" selection-enabled items="[[listItems_]]"
-          scroll-target="container" selected-item="{{selectedItem}}">
+      <iron-list id="networkList" items="[[listItems_]]"
+          scroll-target="container" preserve-focus>
         <template>
           <network-list-item item="[[item]]"
               show-technology-badge="[[showTechnologyBadge]]"
-              show-buttons="[[showButtons]]" tabindex$="[[tabIndex]]"
+              show-buttons="[[showButtons]]"
+              tabindex$="[[tabIndex]]"
+              focus-row-index="[[index]]"
+              iron-list-tab-index="[[tabIndex]]"
               activation-unavailable="[[activationUnavailable]]"
+              last-focused="{{lastFocused_}}"
+              list-blurred="{{listBlurred_}}"
               device-state="[[deviceState]]">
           </network-list-item>
         </template>

ui/webui/resources/cr_components/chromeos/network/network_list.js

@@ -74,12 +74,49 @@ Polymer({
         return [];
       },
     },
+
+    /**
+     * Used by FocusRowBehavior to track the last focused element on a row.
+     * @private
+     */
+    lastFocused_: Object,
+
+    /**
+     * Used by FocusRowBehavior to track if the list has been blurred.
+     * @private
+     */
+    listBlurred_: Boolean,
   },
 
-  behaviors: [CrScrollableBehavior],
+  behaviors: [CrScrollableBehavior, ListPropertyUpdateBehavior],
 
   observers: ['updateListItems_(networks, customItems)'],
 
+  /** @type {ResizeObserver} used to observer size changes to this element */
+  resizeObserver_: null,
+
+  /** @override */
+  attached() {
+    // This is a required work around to get the iron-list to display on first
+    // view. Currently iron-list won't generate item elements on attach if the
+    // element is not visible. Because there are some instances where this
+    // component might not be visible when the items are bound, we listen for
+    // resize events and manually call notifyResize on the iron-list
+    this.resizeObserver_ = new ResizeObserver(entries => {
+      const networkList =
+          /** @type {IronListElement} */ (this.$$('#networkList'));
+      if (networkList) {
+        networkList.notifyResize();
+      }
+    });
+    this.resizeObserver_.observe(this);
+  },
+
+  /** @override */
+  detached() {
+    this.resizeObserver_.disconnect();
+  },
+
   /** @private {boolean} */
   focusRequested_: false,
 
@@ -89,16 +126,15 @@ Polymer({
   },
 
   /** @private */
-  updateListItems_() {
-    this.saveScroll(/** @type {!IronListElement} */ (this.$.networkList));
-    const beforeNetworks = this.customItems.filter(function(item) {
-      return item.showBeforeNetworksList === true;
-    });
-    const afterNetworks = this.customItems.filter(function(item) {
-      return item.showBeforeNetworksList !== true;
-    });
-    this.listItems_ = beforeNetworks.concat(this.networks, afterNetworks);
-    this.restoreScroll(/** @type {!IronListElement} */ (this.$.networkList));
+  updateListItems_: function() {
+    const beforeNetworks =
+        this.customItems.filter(n => n.showBeforeNetworksList === true);
+    const afterNetworks =
+        this.customItems.filter(n => n.showBeforeNetworksList === false);
+    const newList = beforeNetworks.concat(this.networks, afterNetworks);
+
+    this.updateList('listItems_', item => item.guid, newList);
+
     this.updateScrollableContents();
     if (this.focusRequested_) {
       this.async(function() {
@@ -117,28 +153,4 @@ Polymer({
     item.focus();
     this.focusRequested_ = false;
   },
-
-  /**
-   * Use iron-list selection (which is not the same as focus) to trigger
-   * tap (requires selection-enabled) or keyboard selection.
-   * @private
-   */
-  selectedItemChanged_() {
-    if (this.selectedItem) {
-      this.onItemAction_(this.selectedItem);
-    }
-  },
-
-  /**
-   * @param {!NetworkList.NetworkListItemType} item
-   * @private
-   */
-  onItemAction_(item) {
-    if (item.hasOwnProperty('customItemName')) {
-      this.fire('custom-item-selected', item);
-    } else {
-      this.fire('selected', item);
-      this.focusRequested_ = true;
-    }
-  },
 });

ui/webui/resources/cr_components/chromeos/network/network_list_item.html

@@ -7,6 +7,7 @@
 <link rel="import" href="../../../cr_elements/shared_style_css.html">
 <link rel="import" href="../../../cr_elements/shared_vars_css.html">
 <link rel="import" href="../../../html/i18n_behavior.html">
+<link rel="import" href="../../../html/cr/ui/focus_row_behavior.html">
 <link rel="import" href="cr_policy_network_behavior_mojo.html">
 <link rel="import" href="network_icon.html">
 <link rel="import" href="network_list_types.html">
@@ -21,6 +22,7 @@
       }
 
       #divOuter {
+        height: 100%;
         padding-inline-end: var(--cr-icon-ripple-padding);
       }
 
@@ -54,9 +56,23 @@
       cr-policy-indicator {
         padding: 0 var(--cr-controlled-by-spacing);
       }
+
+      #wrapper {
+        height: 100%;
+      }
     </style>
+    <div id="wrapper" focus-row-container
+         class="layout horizontal center flex">
       <div id="divOuter"
-        class="layout horizontal center flex" actionable>
+           class="layout horizontal center flex"
+           actionable
+           focus-row-control
+           selectable
+           aria-label$="[[rowLabel]]"
+           role="button"
+           focus-type="rowWrapper"
+           on-keydown="onKeydown_"
+           on-click="onSelected_">
         <template is="dom-if" if="[[networkState]]">
           <network-icon is-list-item
               show-technology-badge="[[showTechnologyBadge]]"
@@ -81,14 +97,20 @@
               networkState.source)]]">
           </cr-policy-indicator>
         </template>
-      <template is="dom-if"
-          if="[[isSubpageButtonVisible_(networkState, showButtons)]]" restamp>
-        <cr-icon-button class="subpage-arrow" id="subpage-button"
-            on-click="onSubpageArrowClick_" tabindex$="[[tabindex]]"
-            aria-label$="[[buttonLabel]]">
+        <template is="dom-if" if="[[isSubpageButtonVisible_(networkState, showButtons)]]" restamp>
+          <div>
+            <cr-icon-button class="subpage-arrow"
+                id="subpage-button"
+                on-click="onSubpageArrowClick_"
+                tabindex$="[[tabindex]]"
+                aria-label$="[[buttonLabel]]"
+                focus-row-control
+                focus-type="subpageButton">
             </cr-icon-button>
+          </div>
         </template>
       </div>
+    </div>
   </template>
   <script src="network_list_item.js"></script>
 </dom-module>

ui/webui/resources/cr_components/chromeos/network/network_list_item.js

@@ -13,6 +13,7 @@ Polymer({
   behaviors: [
     CrPolicyNetworkBehaviorMojo,
     I18nBehavior,
+    cr.ui.FocusRowBehavior,
   ],
 
   properties: {
@@ -45,7 +46,6 @@ Polymer({
     tabindex: {
       type: Number,
       value: -1,
-      reflectToAttribute: true,
     },
 
     /**
@@ -53,11 +53,10 @@ Polymer({
      * added as an attribute on this top-level network-list-item, and can
      * be used by any sub-element which applies it.
      */
-    ariaLabel: {
+    rowLabel: {
       type: String,
       notify: true,
-      reflectToAttribute: true,
-      computed: 'getAriaLabel_(item, networkState)',
+      computed: 'getRowLabel_(item, networkState)',
     },
 
     buttonLabel: {
@@ -162,7 +161,7 @@ Polymer({
    * @return {string}
    * @private
    */
-  getAriaLabel_() {
+  getRowLabel_() {
     const NetworkType = chromeos.networkConfig.mojom.NetworkType;
     const OncSource = chromeos.networkConfig.mojom.OncSource;
     const SecurityType = chromeos.networkConfig.mojom.SecurityType;
@@ -344,15 +343,11 @@ Polymer({
    * @private
    */
   onKeydown_(event) {
-    // The only key event handled by this element is pressing Enter when the
-    // subpage arrow is focused.
-    if (event.key !== 'Enter' ||
-        !this.isSubpageButtonVisible_(this.networkState, this.showButtons) ||
-        this.$$('#subpage-button') !== this.shadowRoot.activeElement) {
+    if (event.key !== 'Enter' && event.key !== ' ') {
       return;
     }
 
-    this.fireShowDetails_(event);
+    this.onSelected_(event);
 
     // The default event for pressing Enter on a focused button is to simulate a
     // click on the button. Prevent this action, since it would navigate a
@@ -361,6 +356,22 @@ Polymer({
     event.preventDefault();
   },
 
+  /**
+   * @param {!Event} event
+   * @private
+   */
+  onSelected_(event) {
+    if (this.isSubpageButtonVisible_(this.networkState, this.showButtons) &&
+        this.$$('#subpage-button') === this.shadowRoot.activeElement) {
+      this.fireShowDetails_(event);
+    } else if (this.item.hasOwnProperty('customItemName')) {
+      this.fire('custom-item-selected', this.item);
+    } else {
+      this.fire('selected', this.item);
+      this.focusRequested_ = true;
+    }
+  },
+
   /**
    * @param {!MouseEvent} event
    * @private

ui/webui/resources/cr_components/chromeos/network/network_select.js

@@ -128,7 +128,7 @@ Polymer({
     for (const network of networkList.children) {
       if (network.is === 'network-list-item' &&
           network.$$('#divText').children[0].innerText === name) {
-        return network;
+        return network.shadowRoot.getElementById('divOuter');
       }
     }
     return null;

ui/webui/resources/cr_components/chromeos/os_cr_components.gni

@@ -39,5 +39,7 @@ cr_components_chromeos_auto_imports = [
   "ui/webui/resources/cr_components/chromeos/quick_unlock/lock_screen_constants.html|recordLockScreenProgress,LockScreenProgress",
   "ui/webui/resources/cr_components/chromeos/cellular_setup/webview_post_util.html|postDeviceDataToWebview",
   "ui/webui/resources/html/assert.html|assert,assertNotReached",
+  "ui/webui/resources/html/cr/ui/focus_row_behavior.html|FocusRowBehavior",
+  "ui/webui/resources/html/list_property_update_behavior.html|ListPropertyUpdateBehavior",
   "ui/webui/resources/html/polymer.html|Polymer,flush,html",
 ]