Ember js, show spinner when something is loading in background - asynchronous

Is there a way with EmberJS to show a loading template somewhere when something in my page is loading something?
For example, I have a page with many many songs artists, and each of them have many many songs. I load the page of the artists, and good, but in background I'm loading info about songs of everyone. I simply need a loading spinner somewhere that says to me the site is loading something (for example, there is in "Network" tab of Chrome Developer Tools something pending...)
how to do that in such an elegant Emberjs way?

You can observe the isPending property of Ember.PROMISEPROXYMIXIN like so:
{{#if artist.songs.isPending}}
loading...
{{/if}}

As far as I know (and based on a quick perusal of the API docs) Ember doesn't provide a built-in way to achieve this. Unless I'm wrong, this means you'll need to implement request state tracking yourself.
You could do this in Ember's adapter layer (e.g. add code in app/adapters/application.js), but the simplest solution might be to just work with jQuery directly. There are a few APIs you can use:
jQuery.active, which indicates the number of outstanding requests
ajaxStart and ajaxStop
I'd recommend creating an Ember.Service to track this state-- then you can inject it in any Controller or Component that needs to render a template based on this info. Your Service could look like:
import Ember from 'ember';
export default Ember.Service.extend({
init() {
this._super(...arguments);
const invalidateRequestInProgress = () => {
this.notifyPropertyChange('dummyProperty');
}
$(document).ajaxStart(invalidateRequestInProgress);
$(document).ajaxStop(invalidateRequestInProgress);
},
requestInProgress: Ember.computed('dummyProperty', function() {
return Ember.$.active !== 0;
}),
});
I haven't tested this code, so I'm not sure if it'll work in practice :)

Related

Meteor & Flow Router: Marking Dynamically generated paths as 'active'

Needless to say, my experience with Meteor is lacking. I come from a Rails background, where you can do a lot more logic (and magic) in your views than Meteor.
The situation: I've got some routes that look like /things/:_id, and I've named that route 'thing' because it shows only one thing of a user's many owned things:
FlowRouter.route('/things/:_id', {
name: 'thing',
action() {
BlazeLayout.render('appPage', {app: 'thing', sidebar: "thingsListOnThing", header: 'thingTitle'});
}
});
As you can see, I'm also loading a template I've built to list all of the user's owned things on the sidebar for easy navigation. That template, thingsListOnThing is the target of this question.
Get the gist? I'm able to mark the route that dislays a template with a complete list of a user's things as active using zimme:active-route like so:
// A list of all a user's things
<div class="{{isActiveRoute name='things' class='is-active'}}">
List of Things
</div>
This package is great, but it won't help me with routes that look like /things/:_id because, then every link to each individual thing would be is-active on any thing page, not just the one where the current path's :_id matches the _id of the active thing.
I'm really kind of stuck here. My first guess would be to use template helpers, but I'm confused as to where to get started with that.
If need be, please as me to upload any piece of my code you require. I figured it's such a generic question that you guys probably don't need to see all of my code to understand what I'm trying to accomplish.
Using: zimme:active-route
Template Helpers
Template.listOfThings.helpers({
activeListClass(page) {
const active = ActiveRoute.name('thing') && FlowRouter.getParam('_id') === this._id;
return active && 'active';
},
});
Template HTML:
<a class="{{isActivePath 'thing'}}" href="/things/{{_id}}">
<div class="thingListItem {{activeListClass page}}">
{{title}}
</div>
</a>

Where does Meteor.subscribe() belong?

I just noticed that my subscription code "Meteor.subscribe('my-publications')" at the top of my JS file affects ALL my templates, not just the template that the JS file is created for.
This was unexpected because all the demos did it this way.
Where is the subscription code suppose to be in if I want it to affect one template only? Inside Template.name.created()?
Don't assume the only data in minimongo is what is relevant to your template. Be specific when selecting your data for the template.
You have several options as far as subscriptions go, the most common by far is adding a subscription to the waitOn section of your routes definitions. Using waitOn will result in the subscription being unsubscribed when the route is no longer in use.
Router.map(function() {
this.route('route', {
waitOn: function(){ return Meteor.subscribe("yourSub"; }
});
});
You can also subscribe per template. A package I've created for this purpose can be added via
meteor add elevatedevdesign:template-subscriptions
This pattern will also be coming soon as a part of blaze, but with some slight differences in how you call it. This will automatically unsubscribe when the template is no longer active. It also allow's subs-manager to be subscribed to on template destruction.

Animated page transitions between Iron Router routes with Meteor

Currently, the only solutions I have found for animating between routes is just fade out the current page onBeforeAction and fade in the new page onAfterAction. But this is just lame.
I want to try to execute some really sleek transitions like these.
I believe this requires having multiple pages rendered on the page at the same time, but that seems very resources intensive and doesn't even seem to use iron router at all.
Any ideas how I can implement this?
I use a solution like this http://meteorpad.com/pad/5kii9SRbbnjiTHeQe
The MeteorPad doesn't allow to use IronRouter, so my example doesn't use it. In IronRouter you can use action() method to set "currentPage" session variable and always render "transitioner" template. Something like this:
Router.map(function() {
this.route('home', {
path: '/',
action: function() {
Session.set('currentPage', 'home');
this.render('transitioner');
}
});
this.route('about', {
action: function() {
Session.set('currentPage', 'about');
this.render('transitioner');
}
});
});
I use a wrapper for this. It also helps me to define transition styles and directions.
And be careful with subscriptions/unsubscriptions, becouse previous page will react to subscriptions changes before the transition is compelete!
This question seems to get asked a fair amount and there is no definitive solution, and a lot of answers out there are getting stale, or at least not applicable to the latest iron-router and Meteor 1.0.
I just did a bunch of searching around for the best answer and at least today it seems the packages for this are:
https://github.com/percolatestudio/momentum-iron-router/
and
https://github.com/ccorcos/meteor-transitioner/
The former hasn't been updated in a little while but has lots of commits. The latter has few commits but may be being actively worked on.
I'm in progress on trying them out so if I remember I'll check back in.

Upgrading to new asynchrous Google Analytics code - should you do it?

I had read somewhere and have now forgotten that upgrading to the new asynchronous code will not enable one to track actual clicks for downloading items when user stays on the same page and that for tracking that you need to use the old version of GA code.
My question is, is that still the case and does anyone have any other reasons for not upgrading to use the newer asynchronous tracking?
thanks
Hmm...are you sure the "old" version of GA automatically tracked downloads? AFAIK GA never automatically tracked download links, that you always had to attach GA code (like a _trackEvent call) to your links yourself. But in any case, it's pretty easy to do it yourself, so it's really not a big deal. Plus, you get lots of benefits upgrading, and one day it may not even be an option to stick with the old version...
If you have jQuery you can for example do this:
// file types you want to consider a download
var downloadFileTypes = ['pdf','doc','docx','mp4'];
$(document).ready(function() {
$('a').filter(function() {
var ext = $(this).attr('href').split('.').pop().toLowerCase();
return ( $.inArray(ext, downloadFileTypes )>-1 );
})
.click(function() {
_gaq.push(['_trackEvent', 'Downloads', $(this).attr('href')]);
});
});
If you do not have a framework like jQuery, you can still do this easy enough with .getElementsByTagName() and using regular loops and conditions instead of the jQuery conveniences like .filter and .inArray
edit: Some things to note about that example:
the jQuery code was an example to hook the GA code to standard links pointing to the file types you specify in downloadFiletypes. It will only apply to links that exist at the time the code is executed. If you have links that may be dynamically generated on the page later, consider looking into .on() instead of .click()
you will need to make tweaks to matching links you want to consider downloads if they do not point to regular files with extensions. For instance, some websites have a controller script that expects a parameter with an ID and it dynamically serves up a pdf or whatever..if your files are like this, you will have to alter the logic to look for that instead.

How do I tell when GroundOverlays in kml have finished loading?

I'm doing this:
google.earth.fetchKml(ge, slopehref, function(kmlObject){
if (kmlObject){
ge.getFeatures().appendChild(kmlObject);
// GroundOverlay's still not rendered
}
});
So I know when the kml file is loaded but then it takes a few seconds to load the GroundOverlays. I want to get a callback when the GroundOverlays have rendered. I have been looking for google.earth.addEventListener eventids that might fire when network activity has stopped but I can't find anything about it.
Unfortunately this is not possible, there is no way to do this in the current Api. The best you could do is to put a feature request in for this functionality to be added:
http://code.google.com/p/earth-api-samples/issues/list
There is a similar request already in there as well if you wanted to 'star' it:
http://code.google.com/p/earth-api-samples/issues/detail?id=5

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