Ember Drag Drop
Simple drag and drop addon for your Ember CLI app.
The goal is to allow you to add drag and drop to your app without having to become an expert in the browser's low level D&D API.
To use this addon, you don't need to:
- Know anything about how the browser implements drag and drop.
- Ever deal with a browser drag and drop event, or even know that they exist.
When using this addon, you get to work with objects in your domain layer, just like everywhere else in Ember. The only two things you need to use are (as you might expect) Draggable Object and Draggable Object Target
Requirements
- ember-cli 0.2.7 or higher (may work with lower version, but this is what is tested)
- If you use the sorting object, you will need Ember 1.13.2 or higher.
Installation
ember install ember-drag-drop
Thanks
Huge thanks to ic-droppable, from which I shamelessly stole as promised.
Usage
Primitives
Examples
Mobile and touch events
As of version 0.4.4 you can install the ember-drag-drop-polyfill to enable drag and drop actions on mobile devices. It is my intention to make mobile a first class citizen in this addon, but hopefully this can fill the gaps for now.
Primitives
Draggable Object
The draggable-object
component represents an object you want to drag onto a target.
The two things to provide to the component are:
- The content - Represents the object to be dragged. Will be passed to the target after a completed drag.
- The template code to render for the draggable object
At the start of the drag a property of isDraggingObject will be set to true on the content object and false on drag end.
Optionally you can set actions on the component to get notified on drag start and end. The content value of the current object being dragged is sent as the parameter.
If you wish to have a drag handle in your component to be the trigger for a drag start action, instead of the whole wrapped template you can specify the jquery selector in the component.
There are two action hooks you can call as well. By default on start drag the element being dragged has an opacity of 0.5 set. If you want to override that and apply your own stylings you can use the 'dragStartHook' and/or the 'dragEndHook' The jquery event is passed as the only parameter.
// represents the controller backing the above template
Ember.Controller.extend({
// your regular controller code
actions: {
myStartAction: function(content) {
//Content is the same as the content parameter set above
},
myEndAction: function(content) {
//Content is the same as the content parameter set above
},
}
}
});
Draggable Object Target
The draggable-object-target
represents a place to drag objects. This will trigger an action which accepts the dragged object as an argument.
The two things to provide to the component are:
- The action - Represents the action to be called with the dragged object.
- The template code to render for the target.
The action is called with two arguments:
- The dragged object.
- An options hash. Currently the only key is
target
, which is the draggable-object-target component.
Optionally you can also get an action fired when an object is being dragged over and out of the drop target. No parameter is currently sent with these actions.
// represents the controller backing the above template
Ember.Controller.extend({
// your regular controller code
actions: {
increaseRating: function(obj,ops) {
var amount = parseInt(ops.target.amount);
obj.incrementProperty("rating",amount);
obj.save();
},
myOverAction: function() {
//will notify you when an object is being dragged over the drop target
},
myDragOutAction: function() {
//will notify you when an object has left the drop target area
},
}
}
});
You can check out an example of this is action here
Sorting of objects
We now have a basic sorting capabilities in this library. If you wrap the {{#sortable-objects}}
component around your {{#draggable-object}}
components you can get an array of sorted elements returned.
**Important Note on Ember Versions: If you use Ember version 1.13.2 and above you must user at least addon version 0.3 if you use sorting If you use Ember version 1.12.1 and below you must use 0.2.3 if you use sorting This only applies if you use the sort capabilities, regular dragging is not version specific.
An Example:
On drop of an item in the list, the sortableObjectList is re-ordered and the sortEndAction is fired unless the optional parameter 'enableSort' is false. You can check out an example of this is action here
useSwap defaults to true and is optional. If you set it to false, then the sort algorithm will cascade the swap of items, pushing the values down the list. See Demo
The sortingScope is optional and only needed if you have multiple lists on the screen that you want to share dragging between. See Demo
Note: It's important that you add the isSortable=true to each draggable-object or else that item will be draggable, but will not change the order of any item. Also if you set a custom sortingScope they should be the same for the sortable-object and the draggable-objects it contains.
Test Helpers
When writing tests, there is a drag
helper you can use to help facilitate dragging and dropping. You import it like this:
import { drag } from 'your-app/tests/helpers/ember-drag-drop';
You can pass the CSS selector for the draggable-object-target
and pass a beforeDrop
callback.
An Example:
drag('.draggable-object.drag-handle', {
drop: '.draggable-object-target:eq(1)',
beforeDrop() {
// a chance to inspect state before dropping
}
});
In this example, we're dragging the draggable-object element with CSS selector .draggable-object.drag-handle
and dropping
on a draggable-object-target with the CSS selector draggable-object-target:eq(1)
. Then there's also a chance to
make assertions in the beforeDrop
callback.
TODO
Theses additions to sort are still incoming:
Tests for sortable-objects- Transforms for visual indicator of changing order
Ability to drag between sortable containersSorting of horizontal containers (currently only vertical sorting works)
If anyone has any feedback/ideas on sorting, please open an issue.
Component Class Overrides
For both draggable-object
and draggable-object-target
you can override the default class names and provide your own, or a variable class name by adding an overrideClass property to the component.
An Example:
Examples
Classify Posts
In this example, we have a bunch of unclassified posts that we want to mark either Ready to Publish or Needs Revision.
When you drag a post onto one of the Possible Statuses, it will be:
- Assigned that rating.
- Removed from the Unclassified Posts list, by virtue of now having a status.
app/models/post.js
export default DS.Model.extend({
title: DS.attr('string'),
body: DS.attr('string'),
status: DS.attr('string')
});
app/controllers/posts.js
export default Ember.ArrayController.extend({
unclassifiedPosts: Ember.computed.filterBy('content', 'status', undefined),
actions: {
setStatus: function(post,ops) {
var status = ops.target.status;
post.set("status",status);
post.save();
}
}
}
});
app/templates/posts.hbs