What I want is this (news ticker type functionality):
- Get a list of li’s from a ul tag
- Loop through all the li’s and get the text
- display the text in the console via firefox console.log()
- get the next li and repeat till all li’s have been displayed
That’s the goal, but setTimeout is not running as I thought it would. Only the LAST iteration (“Post Four”) is showing. And that (“Post Four”) is showing four times in a row.
<body>
<ul id="post_list">
<li>Post One</li>
<li>Post Two</li>
<li>Post Three</li>
<li>Post Four</li>
</ul>
<script type="text/javascript">
var ul = document.getElementById('post_list');
var li = ul.getElementsByTagName('li');
for(var x=0; x < li.length; x++){
var li_text = li[x].childNodes[0].nodeValue;
setTimeout(function(){showText(li_text)}, 1000);
}
function showText(text) {
console.log(text);
}
</script>
</body>
The reason this is happening is because of closures. The for loop block has closures around it, so when you reference ‘li_text’ it was always equal the last value that li_text was set to. The for loop does not create a separate closure for each iteration through the loop.