原文鏈接： https://www.npmjs.com/package/draggable
High performance, fully cross browser, full featured drag and drop in a tiny (2k gzipped), dependency-free package.
安裝
>npm i draggable --save
Demo
http://bcherny.github.io/draggable/demos/basic/
Usage
HTML
<div id="id"></div>
JavaScript
Using browser globals:
var element = document.getElementById('id');
var options = {
grid: 10,
onDrag: function(){ ... }
};
new Draggable (element, options);
Using AMD/CommonJS:
var Draggable = require ('Draggable');
var element = document.getElementById('id');
new Draggable (element);
Dependencies
None!
Options
| Option | Type | Default | Description |
|---|---|---|---|
| grid | Number |
0 |
grid size for snapping on drag |
| handle | Element |
null |
the handle of the draggable; if null, the whole element is the handle |
| filterTarget | Function(target) |
null |
prevent drag when target passes this test |
| limit |
Element, Function(x, y, x0, y0), or Object
|
{ x: null, y: null } |
limit x/y drag bounds |
| threshold | Number |
0 |
threshold before drag begins (in px) |
| setCursor |
Boolean (truthy) |
false |
change cursor to move? |
| setPosition |
Boolean (truthy) |
true |
change draggable position to absolute? |
| smoothDrag |
Boolean (truthy) |
true |
snap to grid only when dropped, not during drag |
| useGPU |
Boolean (truthy) |
true |
move graphics calculation/composition to the GPU? (modern browsers only, graceful degradation) |
Events
| Event | Arguments |
|---|---|
| onDrag | element, x, y, event |
| onDragStart | element, x, y, event |
| onDragEnd | element, x, y, event |
Instance methods
| Method | Arguments | Returns | Description |
|---|---|---|---|
| get | --- |
{Object} {x, y} |
Get the current coordinates |
| set |
{Number} x, {Number} y |
instance | Move to the specified coordinates |
| setOption |
{String} property, {Mixed} value |
instance | Set an option in the live instance |
| destroy | --- | --- | Unbind the instance's DOM event listeners |
Notes
Options.limit accepts arguments in several forms:
// no limit
limit: null
// limit x, but leave y unbounded
limit: {
x: [1,10],
y: null
}
// limit both axes
limit: {
x: [1,10],
y: [1,500]
}
// bound x, set y to a constant
limit: {
x: [1,10],
y: 5
}
// bound with an element
limit: document.getElementById('id')
// bound with a custom function
limit: function (
x, // current X coordinate
y, // current Y coordinate
x0, // original X coordinate (where drag was started)
y0 // original Y coordinate (where drag was started)
) {
var radius = 100,
dx = x - x0,
dy = y - y0,
distance = Math.sqrt(dx*dx + dy*dy),
// only allow dragging within a circle of radius 100
outOfRange = distance > radius;
// if our point is outside of the circle, compute the
// point on the circle's edge closest to our point
if (outOfRange) {
x = x0 + radius * (x - x0) / distance;
y = y0 + radius * (y - y0) / distance;
}
return {
x: x,
y: y
};
}
Tested on
- Chrome 29 on OSX
- Chrome 28 on Windows
- Firefox 23 on OSX
- Firefox 21 on Windows
- Opera 16 on OSX
- Safari 6 on OSX
- Safari 6 on iPhone4/iOS6
- Safari 6 on iPhone5/iOS6
- Safari 6 on iPad2/iOS6
- Safari 6 on iPad3/iOS6
- Internet Explorer 8-11 on Windows
To do
- Improve performance on old iOS
- Unit tests
