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How can I create a virtual table by reusing fixed number of rows with both mouse wheel and scrollbar support?

I have a large size of data to show as a table on my page and render a table with all the data is too heavy.
So I want to show it as a virtual table that render cells only when necessary.
I know there is a way to fix the header and scroll the tbody, but by that way header widths must be fixed while I want the width could automatically changed according to the data.
So I consider to reuse a fixed number of rows to solve this problem.
I work this out, which works for mouse wheel, but I also want a scrollbar so that users without a mouse wheel could also scroll it.
function updateTable(event) {
var topIdTd = document.getElementById('data-0-id');
var topId = parseInt(topIdTd.innerHTML);
topId += event.deltaY;
for (var i = 0; i < 4; i++) {
document.getElementById('data-' + i + '-id').innerHTML = topId + i;
document.getElementById('data-' + i + '-value').innerHTML = 'looooooooooooooooooooong-value-' + topId + i;
}
return false;
}
var tbody = document.getElementById('table-body');
tbody.onwheel = updateTable;
table {
border-collapse: collapse;
}
table, td, th {
border: 1px solid gray;
}
th {
background-color: #eef;
}
<table>
<thead>
<tr>
<th>
ID
</th>
<th>
Value
</th>
</tr>
</thead>
<tbody id="table-body">
<tr>
<td id="data-0-id">
0
</td>
<td id="data-0-value">
looooooooooooooooooooong-value-0
</td>
</tr>
<tr>
<td id="data-1-id">
1
</td>
<td id="data-1-value">
looooooooooooooooooooong-value-1
</td>
</tr>
<tr>
<td id="data-2-id">
2
</td>
<td id="data-2-value">
looooooooooooooooooooong-value-2
</td>
</tr>
<tr>
<td id="data-3-id">
3
</td>
<td id="data-3-value">
looooooooooooooooooooong-value-3
</td>
</tr>
</tbody>
</table>
How can I create a scrollbar on an unscrollable element?
Or is there any better solutions for this problem?

Highlight multiple rows in several tables

I have a page with several rows containing information, made by several users. I'm looking for a way to highlight the all the users rows on mouseover.
This "Highlight multiple items on hover's condition" almost solved my problem, but since the classes or id's in my problem are dynamic from a database, and would contain an identifier from the DB and are unique each time. I have not been able to apply it.
Example code: https://jsfiddle.net/3cehoh78/
<table class="testtable">
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 1a</td>
<td class="cellclass">Sam</td>
<td class="cellclass">data</td>
</tr>
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 2a</td>
<td class="cellclass">Frodo</td>
<td class="cellclass">data</td>
</tr>
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 3a</td>
<td class="cellclass">Sam</td>
<td class="cellclass">data</td>
</tr>
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 4a</td>
<td class="cellclass">Legoman</td>
<td class="cellclass">data</td>
</tr>
</table>
<br>
<br>
<table class="testtable">
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 1b</td>
<td class="cellclass">Sauron</td>
<td class="cellclass">data</td>
</tr>
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 2b</td>
<td class="cellclass">Sam</td>
<td class="cellclass">data</td>
</tr>
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 3b</td>
<td class="cellclass">Sam</td>
<td class="cellclass">data</td>
</tr>
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 4b</td>
<td class="cellclass">Legoman</td>
<td class="cellclass">data</td>
</tr>
<tr id="uniqueIDthatcantbechanged">
<td class="cellclass">Line 5b</td>
<td class="cellclass">Frodo</td>
<td class="cellclass">data</td>
</tr>
</table>
In this example, I want all the rows with "Sam" to be highlighted on mouseover on one of them, so rows 1a,3a,2b,3b.
I was thinking of adding a class to all the Sam rows when generating the tables (Sam has a unique user ID), but how do I then change css that affects all the rows on mouseover (and not just one).
Please note that I cant pre-add css classes for all the unique userID's, this is just an example.

Here a solution with JQuery https://jsfiddle.net/3cehoh78/5
$(document).ready(function() {
$( "tr" ).hover(function() {
var search = $(this).find("td:eq(1)").text();
$( ".highlight" ).removeClass("highlight");
$("tr:contains('"+search+"')").addClass("highlight");
}); /* END HOVER */
}); // end document ready

Simple solution without using jQuery and co: https://jsfiddle.net/3cehoh78/3/
var rows = [].slice.call(document.querySelectorAll('.testtable tr'));
rows.forEach(function(row) {
row.addEventListener('mouseover', function() {
resetHighlighting();
var name = row.querySelector('td:nth-child(2)').textContent;
rows.forEach(function(r) {
if (r.querySelector('td:nth-child(2)').textContent === name) {
r.classList.add('highlighted');
}
});
});
});
function resetHighlighting() {
rows.forEach(function(row) {
row.classList.remove('highlighted');
});
}

Here's another way using vanilla-JavaScript.
var tds = document.querySelectorAll('td');
var highlight = function () {
// take this person's name from the 2nd cell
var name = this.parentNode.children[1].innerHTML;
// highlight cells with same name
tds.forEach(function (td) {
var tr = td.parentNode;
// compare other's person name with this person name
// highlight if there is a match
tr.classList.toggle('highlight', tr.children[1].innerHTML === name)
});
}
// attach an event listener to all cells
tds.forEach(function (td) {
td.onmouseover = highlight;
});
Demo

Highlight table cell based on vertical and horizontal headers

I have a "football squares" game going, and I would like to highlight cells of the winners based on the top and side headers.
Now, I know they're not really headers but they serve the same purpose.
My table is located at this jfiddle: https://jsfiddle.net/8ybtntqg/
What I want to do is this:
Let's say the winner would be whoever is in the cell that lines up with TeamA - 2 and TeamZ - 9. That would be Mitch. I want to highlight Mitch's cell. How would I do this with Javascript or Jquery? I know how to do it if I was just looking for the word "Mitch", but I want to automatically do it, based on the numbers of TeamA and TeamZ.
I have this so far, but of course that only highlights the name but it's the only place I knew to start:
$('#table_id td').each(function() {
if ($(this).text() == 'Mitch') {
$(this).closest('td').css('background-color', '#f00');
}
});

You can get the index of the column and row using jQuery's filter() method.
That will give you direct access to the cell like so:
$('tr').eq(row).find('td').eq(col).css('background-color', '#f00');
Snippet:
function highlight(teamA, teamZ) {
var col, row;
col = $('#table_id td').filter(function() { //return column of teamA
return $(this).html() === teamA.replace(' - ', '<br>');
}).index();
row = $('#table_id tr').filter(function() { ////return row of teamZ
return $(this).html().indexOf(teamZ.replace(' - ', '<br>')) > -1;
}).index();
$('tr').eq(row).find('td').eq(col).css('background-color', '#f00');
}
highlight('TeamA - 2', 'TeamZ - 9');
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<table border="1" id="table_id">
<tr>
<td>Squares</td>
<td>TeamA<br>1</td>
<td>TeamA<br>2</td>
<td>TeamA<br>3</td>
<td>TeamA<br>4</td>
<td>TeamA<br>5</td>
<td>TeamA<br>6</td>
<td>TeamA<br>7</td>
<td>TeamA<br>8</td>
<td>TeamA<br>9</td>
<td>TeamA<br>0</td>
</tr>
<tr>
<td>TeamZ<br>3</td>
<td bgcolor="#89ff89">Mark</td>
<td bgcolor="#89ff89">John</td>
</tr>
<tr>
<td>TeamZ<br>5</td>
<td bgcolor="#89ff89">Mike</td>
<td bgcolor="#89ff89">Earl</td>
</tr>
<tr>
<td>TeamZ<br>8</td>
<td bgcolor="#89ff89">Morris</td>
<td bgcolor="#89ff89">Brice</td>
</tr>
<tr>
<td>TeamZ<br>7</td>
<td bgcolor="#89ff89">Taylor</td>
<td bgcolor="#89ff89">Evan</td>
</tr>
<tr>
<td>TeamZ<br>9</td>
<td bgcolor="#89ff89">Mandy</td>
<td bgcolor="#89ff89">Mitch</td>
</tr>
<tr>
<td>TeamZ<br>2</td>
<td bgcolor="#89ff89">Tony</td>
<td bgcolor="#89ff89">Jennifer</td>
</tr>
<tr>
<td>TeamZ<br>1</td>
<td bgcolor="#89ff89">Kristen</td>
<td bgcolor="#89ff89">Hector</td>
</tr>
<tr>
<td>TeamZ<br>4</td>
<td bgcolor="#89ff89">Gabby</td>
<td bgcolor="#89ff89">David</td>
</tr>
<tr>
<td>TeamZ<br>6</td>
<td bgcolor="#89ff89">George</td>
<td bgcolor="#89ff89">Steffanie</td>
</tr>
<tr>
<td>TeamZ<br>0</td>
<td bgcolor="#89ff89">Breck</td>
<td bgcolor="#89ff89">Terry</td>
</tr>
</table>

You can iterate over all the table elements to find the matching values, then use CSS selectors to highlight the matched field. Something like this will work:
winningAScore = 2;
winningZScore = 9;
//get top row
counter = 0;
$('#table_id tr:first-child td').each(function() {
var strOut = $(this).html().replace(/Team[A-z]<br>/g,'');
if(!isNaN(strOut) && strOut == winningAScore) {
posnX = counter;
}
counter++;
})
//get first column row
counter = 0;
$('#table_id tr td:first-child').each(function() {
var strOut = $(this).html().replace(/Team[A-z]<br>/g,'');
if(!isNaN(strOut) && strOut == winningZScore) {
posnY = counter;
}
counter++;
})
$('tr:eq('+posnY+') td:eq('+posnX+')').css('background-color', 'red');
You can see it working in this JS Fiddle: https://jsfiddle.net/igor_9000/8ybtntqg/1/

You can do index based detect and selection in jQuery like so: $('tr:eq(2) td:eq(1)').css('background-color', 'red');
Example: http://codepen.io/anon/pen/EPLNvB

Adding ClassName of td with in the click event

I have use the following code snippet to create the tr of table in Jquery.
Code snippet:
<tr>
<td class="rowcell">
<div>
<div class="intend" style="width: 24px; height: 1px; float: left;"></div>
<div class="style='float:" left'=""></div>
<div style="width: 10px; height: 1px; float: left;"></div>
<div>Task 3</div>
</div>
</td>
<td class="rowcell">
<div>01/01/2013</div>
</td>
<td class="rowcell">
<div>01/05/2013</div>
</td><td class="rowcell">
<div>5 days</div>
</td>
<td class="rowcell">
<div>77</div>
</td>
</tr>
In this case I have invoke the click event for parent of the table. with in the click event I have use the following code snippet to change the className of td to apply the Selection Background, but ClassName cannot change in this case.
Code Snippet
//Here $ganttGridRows table rows.
var $ganttGridRows = $(this.getGanttGridTreeRows());
//Clicking in the row
var row = $target.closest('tr');
var index = $ganttGridRows.index(row);
var item = this.model.currentViewRange[recordIndex];
this.model.selectedRow = this.model.ganttRecords.indexOf(item);
var args = {};
if (this.model.selectedRow != -1)
args = { currentRowIndex: this.model.selectedRow, currrentRow: $ganttGridRows.eq(this.model.selectedRow), currentData: this.model.ganttRecords[this.model.selectedRow] };
if (this._trigger("rowSelecting", args))
return;
this.cleanUpSelection();
this._selectedRowsIndexes = [];
var cell = $target.closest('td');
//Here index is the rowindex of the selected row
$($ganttGridRows[index]).find('.rowcell').addClass("selectionbackground");
But in this did not working while using div with in the td. But if I use without div in td and directly assign the text like below code snippet and it is working fine for me.
Code Snippet
<tr>
<td class="rowcell">Task 1</td>
<td class="rowcell">01/01/2013</td>
<td class="rowcell">01/05/2013</td>
<td class="rowcell">5 days</td>
<td class="rowcell">31</td>
</tr>
Can you pleases any look in to this and provide suggestion to resolve this problem and , explain what is the reason for this behaviour.

How can I get the corresponding table column (td) from a table header (th)?

I want to get the entire column of a table header.
For example, I want to select the table header "Address" to hide the address column, and select the "Phone" header to show the correspondent column.
<table>
<thead>
<tr>
<th id="name">Name</th>
<th id="address">Address</th>
<th id="address" class='hidden'>Address</th>
</tr>
</thead>
<tbody>
<tr>
<td>Freddy</td>
<td>Nightmare Street</td>
<td class='hidden'>123</td>
</tr>
<tr>
<td>Luis</td>
<td>Lost Street</td>
<td class='hidden'>3456</td>
</tr>
</tbody>
I want to do something like http://www.google.com/finance?q=apl (see the related companies table) (click the "add or remove columns" link)

Something like this would work -
$('th').click(function() {
var index = $(this).index()+1;
$('table td:nth-child(' + index + '),table th:nth-child(' + index + ')').hide()
});
The code above will hide the relevant column if you click on the header, the logic could be changed to suit your requirements though.
Demo - http://jsfiddle.net/LUDWQ/

With a couple simple modifications to your HTML, I'd do something like the following (framework-less JS):
HTML:
<input class="chk" type="checkbox" checked="checked" data-index="0">Name</input>
<input class="chk" type="checkbox" checked="checked" data-index="1">Address</input>
<input class="chk" type="checkbox" checked="checked" data-index="2">Phone</input>
<table id="tbl">
<thead>
<tr>
<th>Name</th>
<th>Address</th>
<th>Phone</th>
</tr>
</thead>
<tbody>
<tr>
<td>Freddy</td>
<td>Nightmare Street</td>
<td>123</td>
</tr>
<tr>
<td>Luis</td>
<td>Lost Street</td>
<td>3456</td>
</tr>
</tbody>
Javascript:
var cb = document.getElementsByClassName("chk");
var cbsz = cb.length;
for(var n = 0; n < cbsz ; ++n) {
cb[n].onclick = function(e) {
var idx = e.target.getAttribute("data-index");
toggleColumn(idx);
}
}
function toggleColumn(idx) {
var tbl = document.getElementById("tbl");
var rows = tbl.getElementsByTagName("tr");
var sz = rows.length;
for(var n = 0; n < sz; ++n) {
var el = n == 0 ? rows[n].getElementsByTagName("th")[idx] : rows[n].getElementsByTagName("td")[idx];
el.style.display = el.style.display === "none" ? "table-cell" : "none";
}
}
http://jsfiddle.net/dbrecht/YqUNz/1/
I added the checkboxes as it doesn't make sense to bind the click to the column headers as you won't be able to toggle the visibility, only hide them.

You can do something with CSS, like:
<html>
<head>
<style>
.c1 .c1, .c2 .c2, .c3 .c3{
display:none;
}
</style>
</head>
<body>
<table class="c2 c3">
<thead>
<tr>
<th id="name" class="c1">Name</th>
<th id="address" class="c2">Address</th>
<th id="phone" class="c3">Phone</th>
</tr>
</thead>
<tbody>
<tr>
<td class="c1">Freddy</td>
<td class="c2">Nightmare Street</td>
<td class="c3">123</td>
</tr>
<tr>
<td class="c1">Luis</td>
<td class="c2">Lost Street</td>
<td class="c3">3456</td>
</tr>
</tbody>
</table>
</body>
</html>
To hide a column, you add with Javascript the corresponding class to the table. Here c2 and c3 are hidden.
You could add dynamically the .c1, .c2,... in a style tag, or define a maximum number.

The easiest way to do this would be to add a class to each td that matches the class of the header. When you click the , it checks the class, then hides every td with that class. Since only the s in that column would hide that class, it would effectively hide the column.
<table>
<thead>
<th>Name</th>
<th>Address</th>
</thead>
<tbody>
<tr>
<td class="Name">Joe</td>
<td class="Address">123 Main St.
</tbody>
</table>
And the script something like:
$('th').click( function() {
var col = $(this).html(); // Get the content of the <th>
$('.'+col).hide(); // Hide everything with a class that matches the col value.
});
Something like that, anyway. That's probably more verbose than it needs to be, but it should demonstrate the principle.
Another way would be to simply count how many columns over the in question is, and then loop through each row and hide the td that is also that many columns over. For instance, if you want to hide the Address column and it is column #3 (index 2), then you would loop through each row and hide the third (index 2).
Good luck..

Simulating the Google Finance show/hide columns functionality:
http://jsfiddle.net/b9chris/HvA4s/
$('#edit').click(function() {
var headers = $('#table th').map(function() {
var th = $(this);
return {
text: th.text(),
shown: th.css('display') != 'none'
};
});
var h = ['<div id=tableEditor><button id=done>Done</button><table><thead><tr>'];
$.each(headers, function() {
h.push('<th><input type=checkbox',
(this.shown ? ' checked ' : ' '),
'/> ',
this.text,
'</th>');
});
h.push('</tr></thead></table></div>');
$('body').append(h.join(''));
$('#done').click(function() {
var showHeaders = $('#tableEditor input').map(function() { return this.checked; });
$.each(showHeaders, function(i, show) {
var cssIndex = i + 1;
var tags = $('#table th:nth-child(' + cssIndex + '), #table td:nth-child(' + cssIndex + ')');
if (show)
tags.show();
else
tags.hide();
});
$('#tableEditor').remove();
return false;
});
return false;
});

jQuery('thead td').click( function () {
var th_index = jQuery(this).index();
jQuery('#my_table tbody tr').each(
function(index) {
jQuery(this).children('td:eq(' + th_index + ');').each(
function(index) {
// do stuff here
}
);
}
);
});

here's a working fiddle of this behaviour:
http://jsfiddle.net/tycRW/
of course, hiding the column with out hiding the header for it will have some strange results.