I am working on a way to flash a browser tab when a new message appears in a table. I have the flashing of the tab part working, my only problem is that I can't seem to get it to flash when a message is received (which is the whole point of my exercise :) )
The newMessage()
function is working fine, I just can't seem to get the notification()
function to work.
My code is as follows:
function newMessage()
{
var oldTitle = "Your Page";
var msg = "New Message";
var timeout = setInterval(function()
{
document.title = document.title == msg ? '' : msg;
}, 1000);
window.onmousemove = function() {
clearInterval(timeout);
document.title = oldTitle;
window.onmousemove = null;
};
}
function notification()
{
var index = 2;
var content = document.getElementById('refreshMessages').childNodes[index];
var content = document.getElementById('refreshMessages').getElementByTagName("tr")[1];
var knownContent = content.toString();
updater.start();
updater2.start();
var newContent = document.getElementById('refreshMessages').childNodes[index];
var newContent = document.getElementById('refreshMessages').getElementByTagName("tr")[1];
if(knownContent != newContent.toString())
{
newMessage();
knownContent = newContent;
}
else if(knownContent = newContent.toString())
{
alert("No need to flash title.");
}
}
notification();
In the notification()
function, I am trying to call the newMessage()
function by comparing the strings at the appropiate cell in the table.
I put the alert()
into the else if just to see if it would be called, but it does not happen. update.start()
and update2.start()
are carried out however, as I can see the messages appearing in the table.
I would be happier to use JavaScript but I am open to jQuery also.
My JavaScript is very very rusty so excuse me if I have made any silly mistakes!
Thanks,
Chuck
You have several mistakes in function notification(), see my comments:
function notification()
{
var index = 2;
//Why are you assigning value to "content" for twice?
var content = document.getElementById('refreshMessages').childNodes[index];
/*
* function getElementByTagName is undefined, should be getElementsByTagName,
* 's' is missing. And [1] means the second one not the first one, make sure
* that's exactly what you want.
*/
var content = document.getElementById('refreshMessages').getElementByTagName("tr")[1];
/*
* content is a tr dom object, content.toString() is something like "[object]".
* If you want to get content inside a cell, you should use cell.innerHTML.
* e.g. A table:
* <table id="refreshMessages">
* <tr><td>Hello world</td></tr>
* </table>
* var table = document.getElementById('refreshMessages');
* var firstTr = table.getElementsByTagName("tr")[0];
* var firstTd = firstTr.getElementsByTagName("td")[0];
* alert(firstTd.innerHTML); //alerts "Hello world"
*/
var knownContent = content.toString();
//I doubt these functions really get invoked cuz there's javascript error above.
updater.start();
updater2.start();
//assigning twice, "getElementByTagName" is missing "s"
var newContent = document.getElementById('refreshMessages').childNodes[index];
var newContent = document.getElementById('refreshMessages').getElementByTagName("tr")[1];
//Remove toString(), use innerHTML i metioned above.
if(knownContent != newContent.toString())
{
newMessage();
knownContent = newContent;
}
//You miss an "=" here, to judge a equals b, you should use "=="
else if(knownContent = newContent.toString())
{
alert("No need to flash title.");
}
}
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