drupal/misc/tableheader.js

109 lines
3.1 KiB
JavaScript

// $Id$
Drupal.behaviors.tableHeader = function (context) {
// Keep track of all header cells.
var cells = [];
var z = 0;
$('table thead:not(.tableHeader-processed)', context).each(function () {
// Find table height.
var table = $(this).parent('table')[0];
var height = $(table).addClass('sticky-table').height();
var i = 0;
// Find all header cells.
$('th', this).each(function () {
// Ensure each cell has an element in it.
var html = $(this).html();
if (html == ' ') {
html = ' ';
}
if ($(this).children().size() == 0) {
html = '<span>'+ html +'</span>';
}
// Clone and wrap cell contents in sticky wrapper that overlaps the cell's padding.
$('<div class="sticky-header" style="position: fixed; visibility: hidden; top: 0px;">'+ html +'</div>').prependTo(this);
var div = $('div.sticky-header', this).css({
'marginLeft': '-'+ $(this).css('paddingLeft'),
'marginRight': '-'+ $(this).css('paddingRight'),
'paddingLeft': $(this).css('paddingLeft'),
'paddingTop': $(this).css('paddingTop'),
'paddingBottom': $(this).css('paddingBottom'),
'z-index': ++z
})[0];
cells.push(div);
// Adjust width to fit cell/table.
var ref = this;
if (!i++) {
// The first cell is as wide as the table to prevent gaps.
ref = table;
div.wide = true;
}
$(div).css('width', parseInt($(ref).width())
- parseInt($(div).css('paddingLeft')) +'px');
// Get position and store.
div.cell = this;
div.table = table;
div.stickyMax = height;
div.stickyPosition = Drupal.absolutePosition(this).y;
});
$(this).addClass('tableHeader-processed');
});
// Track scrolling.
var scroll = function() {
$(cells).each(function () {
// Fetch scrolling position.
var scroll = document.documentElement.scrollTop || document.body.scrollTop;
var offset = scroll - this.stickyPosition - 4;
if (offset > 0 && offset < this.stickyMax - 100) {
$(this).css('visibility', 'visible');
}
else {
$(this).css('visibility', 'hidden');
}
});
};
$(window).scroll(scroll);
$(document.documentElement).scroll(scroll);
// Track resizing.
var time = null;
var resize = function () {
// Ensure minimum time between adjustments.
if (time) {
return;
}
time = setTimeout(function () {
// Precalculate table heights
$('table.sticky-table').each(function () {
this.height = $(this).height();
});
$(cells).each(function () {
// Get position.
this.stickyPosition = Drupal.absolutePosition(this.cell).y;
this.stickyMax = this.table.height;
// Reflow the cell.
var ref = this.cell;
if (this.wide) {
// Resize the first cell to fit the table.
ref = this.table;
}
$(this).css('width', parseInt($(ref).width())
- parseInt($(this).css('paddingLeft')) +'px');
});
// Reset timer
time = null;
}, 250);
};
$(window).resize(resize);
};