Dragdrop.js

This Javascript package implements drag-n-drop functionality in a browser.

Supports:

• Moving an element horizontally, vertically and in both directions
• Snap to grid functionality
• Limitation of moving distance
• Registering of user-defined function on start, move and stop

Tested in the following browsers: IE 6.0, FF 17, Chrome 22, Safari 5.1.1

Dragdrop.js requires Event.js package, which can be acquired at the following links:

Basic usage

Once initialized, Dradrop.js will apply drag-n-drop functionality to all HTML elements with class="draggable":

var evt         = new Event(),
    dragdrop    = new Dragdrop(evt);

Advanced usage

To implement advanced options an element should be attached to Dragdrop.js, it can be done using set method:

var evt         = new Event(),
    dragdrop    = new Dragdrop(evt),
    something   = document.getElementById('something');

dragdrop.set(something, {
    mode: 0,
    minX: 50,
    maxX: 350,
    minY: 50,
    maxY: 350,
    snap: 5,
    onstart: function(element) {
        // do something here
    },
    onmove: function(element) {
        // do something here
    },
    onstop: function(element) {
        // do something here
    }
});

which takes 2 arguments, first is the DOM element to be dragged, and the second is the options object which could have the following properties and values:

• mode (int)
  • 0 - move in both directions (default)
  • 1 - move horizontally
  • 2 - move vertically
• minX (int) - X coordinate limiting the most left position of the element, calculating from 0 (default 0)
• maxX (int) - X coordinate limiting the most right position of the element (default is browser window width)
• minY (int) - Y coordinate limiting the most top position of the element (default 0)
• maxY (int) - Y coordinate limiting the most bottom position of the element (default is browser window height)
• snap (int) - number of pixels to snap the element (default 1)
• onstart - handler for start (mousedown) event
• onmove - handler for move (mousemove) event
• onstop - handler for stop (mouseup) event

All handlers receive DOM node as argument

Some examples:

Move the element:

var evt         = new Event(),
    dragdrop    = new Dragdrop(evt),
    horizontal  = document.getElementById('horizontal'),
    vertical    = document.getElementById('vertical'),
    hLimited    = document.getElementById('horizontal-limited'),
    hSnapped    = document.getElementById('horizontal-snapped');

dragdrop.set(horizontal, {mode: 1});
dragdrop.set(vertical, {mode: 2});
dragdrop.set(hLimited, {mode: 1, minX: 50, maxX: 250});
dragdrop.set(hSnapped, {mode: 1, snap: 50});

For more examples please refer to demo scripts provided with the package.