jquery/drag/drag.js

72 lines
1.8 KiB
JavaScript

$.drug = null;
$.dragstart = function(e)
{
this.dragElement.deltaX = e.clientX - this.dragElement.offsetLeft;
this.dragElement.deltaY = e.clientY - this.dragElement.offsetTop;
// Save CSS
this.dragElement.oldPos = $.css(this.dragElement, 'position');
this.dragElement.oldCursor = $.css(this.dragElement, 'cursor');
this.dragElement.oldUserSelect = $.css(this.dragElement, 'user-select');
$(this.dragElement).css('position', 'absolute')
.css('cursor', 'move')
.css('user-select', 'none');
$.drug = this.dragElement;
};
$.dragstop = function(e)
{
$.drug = null;
// Restore CSS
$(this).css('cursor', this.oldCursor)
.css('user-select', this.oldUserSelect);
}
$.drag = function(e)
{
if ($.drug == null) {
return;
}
// Update position
var nx = (e.clientX - $.drug.deltaX);
var ny = (e.clientY - $.drug.deltaY);
// Bounds check
// Left edge
nx = (nx < 0) ? 0 : nx;
// right edge
nx = (nx + $.drug.offsetWidth) > document.width ? document.width - $.drug.offsetWidth : nx;
// Top
ny = (ny < window.scrollY) ? window.scrollY : ny;
// Bottom
ny = (ny + $.drug.offsetHeight) > window.innerHeight + window.scrollY ? window.innerHeight + window.scrollY - $.drug.offsetHeight: ny;
$($.drug).css('left', nx + 'px')
.css('top', ny + 'px');
};
$.draginit = false;
$.fn.Draggable = function(handle)
{
// Don't add > 1 of these handlers
if (!$.draginit) {
$(document).bind('mousemove', $.drag);
}
return this.each(function()
{
var dhe = handle ? $(this).find(handle) : $(this);
dhe.get(0).dragElement = this;
dhe.bind('mousedown', $.dragstart)
.bind('mouseup', $.dragstop);
});
};