#Animations with ngAnimate
##Objectives
- Use the ngAnimate module to add animations to an application.
- Understand the properties that ngAnimate adds to directives.
##Getting started
Angular supports animations on enter, leave, and move. This is achieved by loading the ngAnimate module, which will automatically add the ng-enter/ng-leave/ng-move classes to your object when it is added/removed.
Animations are only attached to elements that have the following directives:
Directive | Supported Animations |
---|---|
ngRepeat | enter, leave and move |
ngView | enter and leave |
ngInclude | enter and leave |
ngSwitch | enter and leave |
ngIf | enter and leave |
ngClass | add and remove (the CSS class(es) present) |
ngShow & ngHide | add and remove (the ng-hide class value) |
form & ngModel | add and remove (dirty, pristine, valid, invalid & all other validations) |
ngMessages | add and remove (ng-active & ng-inactive) |
ngMessage | enter and leave |
Read the ngAnimate Documentation
Load angular-animate.js
using a <script>
tag. Place this in the <head></head>
tags.
<script src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.5.0/angular-animate.js"></script>
Inject the ngAnimate
dependency into your module.
var app = angular.module('AnimationsApp', ['ngAnimate']);
##Defining an animation class
To add an animation to an item simply add a class to that item and define a css animation that requires the item to have both your custom class and ng-enter/ng-leave/ng-move. There are also two additional classes with the -active
postfix that you'll need to define, to represent the final state of the animation.
.myclass.ng-enter, .myclass.ng-move {
//animation here
}
.myclass.ng-leave {
//animation here
}
.myclass.ng-enter.ng-enter-active,
.myclass.ng-move.ng-move-active {
//final animation state
}
.myclass.ng-leave.ng-leave-active {
//final animation state
}
Documentation can be found here.
Here's an example of a div that has the ng-if directive. The div will only appear if $scope.bool
is true
.
This div has the class fade
so it will fade in and out as the ng-if directive adds and removes the div
from the page.
<div ng-if="bool" class="fade">
Fade me in out
</div>
<button ng-click="bool=true">Fade In!</button>
<button ng-click="bool=false">Fade Out!</button>
/* The starting CSS styles for the enter animation */
.fade.ng-enter {
transition:0.5s linear all;
opacity:0;
}
/* The finishing CSS styles for the enter animation */
.fade.ng-enter.ng-enter-active {
opacity:1;
}
/* now the element will fade out before it is removed from the DOM */
.fade.ng-leave {
transition:0.5s linear all;
opacity:1;
}
.fade.ng-leave.ng-leave-active {
opacity:0;
}
We can also use animation libraries, such as animate.css. Add the CDN link.
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.4.0/animate.min.css">
Then add these animations via the animate
CSS property. Note that we're using ng-hide
and ng-hide-remove
for the ng-show
directive. These are the animation directives associated with this particular directive.
.container.ng-hide-remove {
animation: bounceIn 1s;
opacity: 0;
}
.container.ng-hide {
animation: bounceOut 1s;
opacity: 1;
}
.container.ng-hide-remove.ng-hide-remove-active {
opacity: 1;
}
.container.ng-hide.ng-hide-active {
opacity: 0;
}
These CSS-Tricks articles are also great resources when playing with transitions and animations.
Note: Animation classes will only be added to items as they are manipulated using supported directives, like ng-repeat, ng-show, ng-hide, ng-if, etc...
We can define JavaScript animations as well, similar to how we implemented custom filters.
app.animation('.myclass', [function() {
return {
enter: function(element, doneFn) {
// code goes here, then callback
doneFn();
},
leave: function(element, doneFn) {
// code goes here, then callback
doneFn();
}
}
}]);
This block of code attaches an animation to a class and returns an object with the animations we want to run on enter and leave.
For simplicity, we can use jQuery for animations (this isn't too terrible, since we're strictly using jQuery for its animation capabilities). There's also other alternatives for JavaScript animations, like Velocity.js.