ng-drag-to-reorder
Lightweight AngularJS drag and drop functionality to reorder lists without any dependencies other than Angular. Works great with ng-repeats!
Demos:
Install:
$ npm install ng-drag-to-reorder
or
$ bower install ng-drag-to-reorder
Inject into your Angular app
- Add ngDragToReorder as a dependency to your module in your application.
angular.module('yourApp', ['ngDragToReorder']);
How to Use:
- For the most basic usage just add the
drag-to-reorder
attribute to your list items and pass it the list.
<ul>
<li ng-repeat="avenger in $ctrl.avengers" drag-to-reorder="$ctrl.avengers">
<span ng-bind="avenger.rank"></span>
<span ng-bind="avenger.name"></span>
</li>
</ul>
- When you drop an item, the
dragToReorder_drop
event is broadcasted and will contain the relevant data, allowing your controllers to know when the list has been reordered and react to the changes. - In your controller, you can listen for the event with something similar to below:
$scope.$on('dragToReorder_drop', function (evt, data) {
data.item
data.newIndex
data.prevIndex
data.list
});
CSS Classes:
When you start dragging the element, different classes are added to the element being dragged as well as the elements you are dragging over.
(All classes are added to the elements containing the drag-to-reorder
attribute)
dtr-dragging
is added to the element that is being dragged when you start to drag it.dtr-over
is added to the element you are hovering over.dtr-dropping-above
is added to the element if you are hovering above the the middle point of the element. ***dtr-dropping-below
is added to the element if you are hovering below the the middle point of the element. ***dtr-transition
is added to the dragged element when you start to drag it, but is removed on a delay after being dropped.
This default delay is 1 second (1000 ms), but can be designated by using the dtr-transition-timeout
attribute (see Options below).
*** Important: The class dtr-dropping-above
or dtr-dropping-below
will also be added to the previous or next sibling element of the one you are hovering over.
Depending on which class the element you are hovering over has will determine which sibling will have a class added. (See example below...)
E.g. If you have Elements 1-10. And you begin dragging Element 1. Element 1 will have the dtr-dragging
and dtr-transition
classes added to it.
Let's say you drag Element 1 and are hovering over Element 5. Element 5 will have the dtr-over
class and either the dtr-dropping-above
class if the mouse is above the
halfway point (offsetY) or dtr-dropping-below
if below it. If above it, the previous sibling above (Element 4) will have the dtr-dropping-below
class added to it.
If below the halfway point, the next sibling below (Element 6) will have the dtr-dropping-above
class added to it.
After you drop Element 1, the dtr-dragging
class is removed immediately, followed by the dtr-transition
class one second later or after the number of milliseconds passed
in via the dtr-transition-timeout
attribute (see Options below). This allows for more flexibility in how you want to style the elements during the drag and drop process.
Options:
dtr-init
allows you turn the drag and drop functionality on and off. You can pass it an expression to observe and will add or remove the event listeners based on a true/false value.
<ul>
<li ng-repeat="avenger in $ctrl.avengers"
drag-to-reorder="$ctrl.avengers"
dtr-init="{{$ctrl.draggable}}">
<span ng-bind="avenger.rank"></span>
<span ng-bind="avenger.name"></span>
</li>
</ul>
<button ng-click="$ctrl.toggleDrag()">Toggle Drag and Drop</button>
this.draggable = false;
this.toggleDrag = () => this.draggable = !this.draggable;
dtr-transition-timeout
allows you to set the timeout period (in milliseconds) for when the dtr-transition
class is removed from the dragged element.
This is just an available option in case you want to add some custom animation.
<ul>
<li ng-repeat="avenger in $ctrl.avengers"
drag-to-reorder="$ctrl.avengers"
dtr-transition-timeout="5000">
<span ng-bind="avenger.rank"></span>
<span ng-bind="avenger.name"></span>
</li>
</ul>
- You can import the ngDragToReorder service into your controller and check to see if drag and drop functionality is supported by your
browser. The
drag-to-reorder
directive uses this service to prevent itself from wiring up event listeners if the browser doesn't support
it. You can use the same service if you want to show or hide and buttons or other UI based on browser support.
<ul>
<li ng-repeat="avenger in $ctrl.avengers"
drag-to-reorder="$ctrl.avengers"
dtr-init="{{$ctrl.draggable}}">
<span ng-bind="avenger.rank"></span>
<span ng-bind="avenger.name"></span>
</li>
</ul>
<button ng-if="$ctrl.isSupported" ng-click="$ctrl.toggleDrag()">Toggle Drag and Drop</button>
function exampleComponentController(ngDragToReorder, $scope) {
this.isSupported = ngDragToReorder.isSupported();
this.draggable = false;
this.toggleDrag = () => this.draggable = !this.draggable;
}