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JavaScript problem to reload images

Posted on 2008-10-27
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Last Modified: 2013-12-07
Hello,

I have made a code who reload an image in an infinite loop.

But the problem is that the numbers of elements just growing up with the time, and on my iPhone with Mobile Safari, after a moment, the reloads just stop.

I think it's because of a memory saturation.

How can I do to "free" olds images ?

Sorry for my ugly english, and thanks in advance !
<html>
	<script type="text/javascript" language="JavaScript">
	
			image1 = new Image();
			image2 = new Image();
 
	
		function reloadImage() {
 
			date = new Date();
 
			document.getElementById("texte").innerHTML = date.getTime();  
			
			image1.src = 'image.php?time=' + date.getTime();
			image2 = image1;
			document.getElementById("webcam").src = image2.src;
		}
		
		function reloadTimer() {
			setTimeout("reloadImage()", 500);
		}
 
	</script>
	
	<div id="texte" >XXXX</div>
	
	<img id="webcam" onLoad="reloadTimer()" src="image.php">
</html>

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Question by:Valty
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9 Comments
 
LVL 12

Expert Comment

by:jazzIIIlove
ID: 22816350
Hi there;

<<I have made a code who reload an image in an infinite loop.

Why is that? Purpose?

<<How can I do to "free" olds images ?

What's that?

Best regards...
0
 

Author Comment

by:Valty
ID: 22816431
Hello jazzllllove, thanks you for your fast answer

My code can download a picture of my webcam updated regularly. A sort of streaming, but with a single image.

I do JavaScript for a short time, I wanted to know if it was necessary to "liberate" the memory of the old images, or if my problem is not here.

Regards,
0
 
LVL 12

Accepted Solution

by:
jazzIIIlove earned 250 total points
ID: 22816623
A nice tutorial related with your problem:

http://www.javascriptkit.com/javatutors/closuresleak/index.shtml
0
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Author Comment

by:Valty
ID: 22816768
I have read the link, but I'm not really familiar with this.

Are you sure the problem I have is in relation with memory leaks ?

I would be very grateful if you could give me a sample code
0
 
LVL 18

Assisted Solution

by:Pawel Witkowski
Pawel Witkowski earned 250 total points
ID: 22819946
I think that its more related with cache in browsers rather than memory leaks.

You can try      delete     statement, but i never tried that :(

But first of all... i dont know how this should work. You have setTimeout (so it will fire a function once) and there is no more call to reloadImages()  so after one change there will be nothing more. Just try setInterval, od use setTimeout again at the end of reloadImages function.

And as i said try before adding new Image just put  delete image1 and delete image2 maybe this will help

regards
0
 

Author Comment

by:Valty
ID: 22820611
Hello wilq32, thanks you for your answer

I have already tested with delete, but according to this post, my problem seems to be a specific mobile safari problem, because I have not this problem with other browsers :

http://groups.google.com/group/iphonewebdev/browse_thread/thread/78eeb249726f27f6?hl=en
0
 
LVL 18

Expert Comment

by:Pawel Witkowski
ID: 22820729
nothing more to add :( just wait for new version of mobile browser..
0
 

Author Comment

by:Valty
ID: 22823938
Yes, I think this is the best I can do for the moment, I assign the points !
0
 

Author Closing Comment

by:Valty
ID: 31510496
Thanks !
0

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