Unhighlighting the last clicked row in a table

**jason_kelly** · 01-16-2013, 03:40 AM

Hello,

The below code works great except for the fact that it does not unhighlight the last row that was clicked on. For example, if I were to click on a new row, it would change color which is perfect.

However, if I were to select another row, the previous selected row does not change back to its default color (white). How can the code below be modified so as to restore the previous clicked row to its original color if a new row has been clicked on?

Code:

<!DOCTYPE html>
<html>
<head>
<style type="text/css">
#mstrTable {
     border: 1px solid black
}
#mstrTable td, th {
     border: 1px solid black
}

#mstrTable tr.normal td {
    color: black;
    background-color: white;
}
#mstrTable tr.highlighted td {
    color: white;
    background-color: gray;
}
</style>
</head>
<body>
  <table id="mstrTable">
     <thead>
      <tr> 
        <th>File Number</th>
        <th>Date1</th>
        <th>Date2</th>
        <th>Status</th>
        <th>Num.</th>
      </tr>
    </thead>
    <tbody>
      <tr> 
        <td>KABC</td>
        <td>09/12/2002</td>
        <td>09/12/2002</td>
        <td>Submitted</td>
        <td>0</td>

      </tr>
      <tr> 
        <td>KCBS</td>
        <td>09/11/2002</td>
        <td>09/11/2002</td>
        <td>Approved</td>
        <td>1&nbsp;</td>
      </tr>

      <tr> 
        <td>WFLA</td>
        <td>09/11/2002</td>
        <td>09/11/2002</td>
        <td>Submitted</td>
        <td>2</td>
      </tr>
      <tr> 
        <td>WTSP</td>
        <td>09/15/2002</td>
        <td>09/15/2002</td>
        <td>In-Progress</td>
        <td>3</td>
      </tr>
    </tbody>
  </table>

<script type="text/javascript">
//assumes one thead and one tbody

var table = document.getElementById("mstrTable");
var thead = table.getElementsByTagName("thead")[0];
var tbody = table.getElementsByTagName("tbody")[0];

tbody.onclick = function (e) {
   e = e || window.event;
   var td = e.target || e.srcElement; //assumes there are no other elements inside the td
   var row = td.parentNode;
   row.className = row.className==="highlighted" ? "" : "highlighted";
}

thead.onclick = function (e) {
   e = e || window.event;
   var th = e.target || e.srcElement;  //assumes there are no other elements in the th
   alert(th.innerHTML);
}
</script>
</body>
</html>

**djr33** · 01-16-2013, 04:16 AM

Somehow figuring out the previously row would be very difficult. But there are two easier ways to work around this:

1. Turn off highlighting on all rows. Then turn it on for the new row.

2. Store a variable called "oldrow" every time a row is clicked, then use that to later find the row and unhighlight it. The order is as follows:
i) check if "oldrow" exists, and if so unhighlight it.
ii) highlight the current row
iii) set the current row as "oldrow".

I think option (2) would be a lot easier than option (1), but both are possible. They might have slightly different effects, so think about that too. (For example, if you ever WANT more than one row highlighted, option (1) won't work.)

**vwphillips** · 01-16-2013, 09:42 AM

Code:

<!DOCTYPE html>
<html>
<head>
<style type="text/css">
#mstrTable {
     border: 1px solid black
}
#mstrTable td, th {
     border: 1px solid black
}

#mstrTable tr.normal td {
    color: black;
    background-color: white;
}
#mstrTable tr.highlighted td {
    color: white;
    background-color: gray;
}
</style>
</head>
<body>
  <table id="mstrTable">
     <thead>
      <tr>
        <th>File Number</th>
        <th>Date1</th>
        <th>Date2</th>
        <th>Status</th>
        <th>Num.</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td>KABC</td>
        <td>09/12/2002</td>
        <td>09/12/2002</td>
        <td>Submitted</td>
        <td>0</td>

      </tr>
      <tr>
        <td>KCBS</td>
        <td>09/11/2002</td>
        <td>09/11/2002</td>
        <td>Approved</td>
        <td>1&nbsp;</td>
      </tr>

      <tr>
        <td>WFLA</td>
        <td>09/11/2002</td>
        <td>09/11/2002</td>
        <td>Submitted</td>
        <td>2</td>
      </tr>
      <tr>
        <td>WTSP</td>
        <td>09/15/2002</td>
        <td>09/15/2002</td>
        <td>In-Progress</td>
        <td>3</td>
      </tr>
    </tbody>
  </table>

<script type="text/javascript">
//assumes one thead and one tbody

var table = document.getElementById("mstrTable");
var thead = table.getElementsByTagName("thead")[0];
var tbody = table.getElementsByTagName("tbody")[0];

tbody.onclick = function (e) {
   e = e || window.event;
   var td = e.target || e.srcElement; //assumes there are no other elements inside the td
   var row = td.parentNode;
   if (this.lst&&this.lst!=row){
    this.lst.className='';
   }
   row.className = row.className==="highlighted" ? "" : "highlighted";
   this.lst=row;
}

thead.onclick = function (e) {
   e = e || window.event;
   var th = e.target || e.srcElement;  //assumes there are no other elements in the th
   alert(th.innerHTML);
}
</script>
</body>
</html>