AngularJS: Triggering a Javscript function after rendering an Element Directive

I recently tried to find an elegant solution to a conundrum with AngularJS, but could only find one working solution.

My problem:

I was trying to trigger a Javascript function that needed to be run after all of the elements on a page were loaded. (In my case, after an AngularJS element directive had run and loaded a grid view dynamically). I realized that since I was trying to alter a DOM element after a DOM change that was caused by a directive, I could not use ng-view and $viewContentLoaded, a normal JQuery $(document).ready call, or an onChange event of the div (since that only applies to input types).

The solution:

on the html page side I simply added the “element-watch” tag to the div which already had my element directive.

Posting a Project to Hackster.io

(Update 2/18/2015):  I received an email from Ben, one of the Hackster.io founders in response to the feedback I had in my blog. In it he mentioned that they had already been working to improve some of the areas I mentioned and were definitely open to suggestions for improvement. I am psyched about their future updates and the possibility of improving the community with a more social experience. Also excited to attend the Hackster Hardware Weekend in Seattle and see what they have in store!

I recently posted up my Internet Connected Spark RGB Strip project to Hackster.io and despite a couple annoyances, found myself being drawn to posting up more content. It has become so common for websites and content aggregators to gamify their content in order to draw people to continue using their system. (Respects,Views, and Rewards in Hackster.io are similar to Likes and Follows in Instagram, or Likes, Views, and Subscribes on Youtube). Something to keep in mind for my future web/mobile projects will be to gamify certain aspects.

hackster

What Hackster.io does well:

  • They provide a broken-down view of projects that might be of interest to Makers and Hackers. (By platform, trending, or latest)
  • They make it somewhat easy to create a project and it’s pretty straightforward.
  • They monitor their content for spam and cool projects.
  • They gameify their content so that as a project creator, you want to make and post more.
  • They have drawn in a lot of cool projects already!

What they need to work on:

  • Adding useful content is WAY too tiresome and formatting is a huge pain on their site (it’s easier to link to other sites where your content is already hosted, but then you are less likely to interest people with your project page).
  • For Github project owners who want to show code or their README has all the content, transferring it over to Hackster.io’s projects should be painless and update when the Github README changes!
  • It would be nice if they were faster about monitoring and responding / notifying a project owner that their project has been accepted and made public.

I will continue to use Hackster.io for posting my projects and I think that with time they will improve their content creation system and gain some real traction for the Maker counterpart to Instructables.

Diving into AngularJS

I’ve heard the name “AngularJS” get dropped here and there for a long time now, so I figured that it was time I delved into it a little to see what the fuss is all about.

Why AngularJS?

  1. They do a good job of making it easy to develop a website in the typical MVC (model, view, controller) fashion.
  2. Re-usability / no-repetitiveness of code with directives for elements, attributes, and class names and ng-repeat
  3. Easy to use filters on objects/data.

Here are some of what I learned from my quick dive into the world of AngularJS:

  • Within a controller, it is always better to create a reference to “this”
  • No need to pull in all the separate javascript files anymore. Bootstrap, JQuery, etc. is all included.
  • create an angular module for every “app”, website, or object based on functionality.
  • add controllers to the app for all reusable functionality / better modeling.
  • using the “ng-{keyword}” tag in your html objects gives you a massive amount of flexibility in showing, hiding, repeating, HTML elements based on JSON data, and 2-way data binding.
  • === is a comparison similar to ==
  • ng-class=”{className:variable === 3}” setting of a class based on a variable
  • INCREDIBLY EASY to use JSON data
  • forms have validity BUILT IN and allow you to toggle things based on the value
  • CSS formatting for input types:
  • Include html templates/files in other pages with:
  • Has services built in:
    • $http for fetching JSON data
    • $log for login messages to the javscript console
    • $filter for filtering an array
    • Example:

Would I use it regularly?

I believe that I have found my replacement for jquery and a good model for javascript development for the web. I definitely will be using it for most (if not all) of my websites.

Resources:

 

Updated Experience with Spark Core

After a week of continual use with the Spark Core I have an updated view on the Spark ecosystem.

It’s incredible how easy it is to develop and connect your core to sites developed in Node.js (check out the project I made: http://sparkrgb.azurewebsites.net/). The biggest part of that project was making sure the RGB strip worked and the UI for the website interface. Connecting the two together was the simplest part. The only major disadvantage to using the Spark ecosystem is the fact that you are required to use their Spark cloud to communicate to your device. (Although they are open sourcing a spark-server on Github, it uses the same format as the Spark Cloud.)

Here are some of my personal remarks on the ecosystem:

  • Connecting the Spark to a Mac is pretty easy through USB, but doing it on your Windows machine requires a little more driver interaction. See my blog post on that here.
  • Resetting your Spark’s preferred WiFi connection with the mobile apps is horrible when you compare it to the simplicity of using the command-line interface on your development machine through USB.
  • The Spark Core remembers 7 WiFi credentials. If you add an 8th it will remove the 1st.
  • In order to compile an INO into the firmware, an internet connection is needed on your development machine at least, so there is no way to develop on a self-contained network even if you do not plan to use internet connected capabilities.

Overall, I think that the Spark ecosystem provides the best experience for developing IoT devices currently.

An Awesome Thumbnail Grid with Expandable Preview

While looking for beautiful ways to display projects, I stumbled on this tutorial: http://tympanus.net/codrops/2013/03/19/thumbnail-grid-with-expanding-preview

The code for which is located here: https://github.com/codrops/ThumbnailGridExpandingPreview

It is purely CSS and javascrip and creates a responsive grid layout that analyzes the location of the object you click and scrolls/resizes appropriately. I’ll DEFINITELY be using this in a few projects in the future.

Add Speech Recognition Easily!

Just found out about a cool HTML5 Web API that is built into Google Chrome.

microphonedisabled

Since it is vendor prefixed, this API will only work if a user’s browser supports it (for now Chrome). The cool thing about it though is that in order to use it on your site, all you need to do is write some javascript that checks for “webkitSpeechRecognition” and then creates an instance of it, and then use it. Combine this with your IoT devices and you’ve got voice enabled commands for your interacting with your devices!

This tutorial walks you through the basics of how it gets integrated:
http://updates.html5rocks.com/2013/01/Voice-Driven-Web-Apps-Introduction-to-the-Web-Speech-API

This is the full sample: https://github.com/GoogleChrome/webplatform-samples

Node.js with SparkJS on a Website

Never used Node.js before? Want to test out SparkJS? This is the guide for you.

Background: I have done some development in Node.js before to build websites and small maker projects, but it has been a while since I touched Node.js, so I needed a refresher when I decided to work with the SparkJS package.

Things you will need:

Install node & npm

This will start up the basic express web server that you can navigate to from a web browser by going to the url: http://localhost:3000/

Create an index.html file in your myapp\views folder with the content from here:

Add another line at the end of the index.jade file that says

The whole project can be found at https://github.com/anthony-ngu/sparkjs-example

In order to download the proper node modules, you will need to run the following command from the example directory:

Reading Material: