Data binding in AngularJS

One of the most important things in AngularJS is the data binding. In fact I think it is so important it should be one of the first things you should get to know if you start to write Angular apps. It should be explained more and it shouldn’t be just “the magic that we won’t cover right now”.

The real magic behind Angular’s data binding is called dirty checking. Basically every time you write

{{myModel}}

in the background a new watch for the expression

myModel

 is being created that on every $digest cycle will be evaluated and if the value of the model is changed, the DOM will be updated. Thanks to this dirty checking we are also able to use plain old JS object as our model. How data binding works is explained in detail in this great article – http://angular-tips.com/blog/2013/08/watch-how-the-apply-runs-a-digest/. I also recommend to read Misko’s answer to this StackOverflow question on why dirty checking is not a bad thing, unless of course it is used in a bad way. This is why we should understand how data binding works.

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Animate ngView transitions in AngularJS

Let me just start this post by saying that AngularJS is awesome! I have been playing with Angular recently and I must say that it has the things I loved in Flex and I missed in JavaScript frameworks. Things like declarative UI, bi-directional binding and a lot more, but now I will not write why Angular is cool.

This post will be covering something that I recently wanted to implement, but it seemed that it not so straight forward – animating ng-views when they change.

http://maverix7.appspot.com/files/ngview/index.html#/viewA

An example of such transitions you can check here  http://code.angularjs.org/1.1.4/docs/api/ng.directive:ngView#animations . As you can see when you click on a link, the view is changed by making this slick slide animation. One thing that we notice is that the view is sliding only in one direction, but it will be really nice to have it both ways, based on the hierarchy of the views.

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