MD Settings: First iteration of searching within settings.

chrome/browser/resources/settings/advanced_page/advanced_page.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview
  * 'settings-advanced-page' is the settings page containing the advanced
  * settings.
  */
 Polymer({
@@ skipping 19 matching lines @@
       notify: true,
     },
   },
 
   /**
    * @type {string} Selector to get the sections.
    * TODO(michaelpg): replace duplicate docs with @override once b/24294625
    * is fixed.
    */
   sectionSelector: 'settings-section',
+
+  /** override */
+  ready: function() {
+    this.fire('advanced-page-ready');

[michaelpg, 2016/06/27 23:00:04]

i'm not sure this event is necessary. ready is called synchronously when this
element is created. this element is created (asynchronously) when the dom-if
becomes truthy.

so, you could use observe DOM changes in settings_main.js:
https://www.polymer-project.org/1.0/docs/devguide/local-dom#observe-nodes

or just schedule an async task.

[dpapad, 2016/06/27 23:37:26]

I tried using observeNodes() (after your suggestion), without success. First I
get a call for an empty text node during startup, then my callback is never
called when the advanced page is rendered. Besides those difficulties, observing
the DOM to catch an event that occurs only one time for the lifetime of the page
seems unnecessary.

Also by "just schedule an async task", do you mean calling this.async() right
after flipping the dom-if boolean? I tried this also, but it ends up not finding
any results in the "Advanced" page, whereas the event + PromiseResolver always
searches at the right time (results are found in the advanced page).

[michaelpg, 2016/06/29 01:18:57]

you could try adding a listener for the dom-if's dom-change event:
https://www.polymer-project.org/1.0/docs/api/dom-if#event-dom-change
and then removing the listener when it fires
Yep, that's what I meant. As a sanity check, you can try calling render() on the
dom-if
which should force it to be created (and ready) immediately. Maybe there are
other async
things going on in wherever the results are? If so, can you guarantee all of
those
are always ready by the time the PromiseResolver is resolved, or is that just
what you've
observed so far?

[dpapad, 2016/06/29 18:20:12]

Removed this event.

+  },
 });