asked on

cycle forward and backward through javascript array

greetings,

i need help cycling through a javascript array. i want to be able to go forwards and backwards onclick.

heres what i'm currently using:

---

             // loads global functions
                  loadGlobalFunctions_retail=function(){
                   // rotates contents every x seconds
                   rotateContent_retail=function(){
                   i_retail++;
                   if(i_retail==message_retail.length){i_retail=0}
                   container_retail.innerHTML=message_retail[i_retail];
                   setTimeout('rotateContent_retail()', 5*1000);
                   }
                   // defines messages array
                   var message_retail=new Array();
                         message_retail[0]='dfngdfngdfngdfngsngsdngsngsdn';
                         message_retail[1]='sdn gs dngsd njsdng fg nhfdngfgdmnsfngd sgn sng sn gsdnggdrg';
                         message_retail[2]='gs lasfl gas;flg as;lg alsjdf ahfg woiehg shdcg8y3trfg8ygsv2ge u yrfg ueyfvg uo5gsdfvogqwfouvgasd fgqowu gfowfgvsjdvg iwgc vlxkchgv lsd gv';
                         message_retail[3]='<img src="images/thumb.gif" width="85" height="81" alt="Thumb" class="thumb"><h2>Artist Name 4</h2><p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad is nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo.</p>';
                         message_retail[4]='<img src="images/thumb.gif" width="85" height="81" alt="Thumb" class="thumb"><h2>Artist Name 5</h2><p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitationo laboris nisi ut aliquip ex ea commodo.</p>';
                         message_retail[5]='<img src="images/thumb.gif" width="85" height="81" alt="Thumb" class="thumb"><h2>Artist Name 6</h2><p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo.</p>';
                         message_retail[6]='<img src="images/thumb.gif" width="85" height="81" alt="Thumb" class="thumb"><h2>Artist Name 7</h2><p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labora. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ip ex ea commodo.</p>';
                   var i_retail=0;
                   var container_retail=document.getElementById('retail_div');
                   // execute rotateContent function
                   rotateContent_retail();
                  }
                  // execute code once page is loaded
              window.onload=loadGlobalFunctions_retail;

---

i also need it to still autorotate. is there anyway i can replace this block:

message_retail[4]='<img src="images/thumb.gif" width="85" height="81" alt="Thumb" class="thumb"><h2>Artist Name 5</h2><p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitationo laboris nisi ut aliquip ex ea commodo.</p>';

w/ an asp variable? i plan to cycle through db records and list these out.

thanks,

ASKER CERTIFIED SOLUTION

b0lsc0tt

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b0lsc0tt

I also modified the id the script got. I used container1 and you should change it back to retail_div.

Let me know if you need help making these changes back to your page's stuff.

bol

dirklance

ASKER

forgive me but how do i call the functions?

i tried:

<div id="retail_div"></div><br />
<a href="javascript:void(0);" onclick="nextItem();">next item</a>

i know i'm missing something there. and how do i set the initial HTML to [0] in the array?

thanks again,

b0lsc0tt

The code should already be set to start with the [0] item in that array. There was a line to do it on the onload event for the window.

// execute code once page is loaded
window.onload=loadGlobalFunctions_retail;

The onclick event in the anchor tag looks good but add a return false to the end.

<a href="javascript:void(0);" onclick="nextItem(); return false;">next item</a>

I usually use # for the href (e.g. href="#") but your value should be fine. If there is still a problem look to see if there is a javascript error but the return false will probably fix it.

Let me know if you have a question or need more info.

bol

dirklance

ASKER

i still can't seem to get it here. i'm getting a 'object expected' error on the line that loads the global.

___

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>

<script type="javascript">
// defines messages array
var message_retail=new Array();
message_retail[0]='0 dfngdfngdfngdfngsngsdngsngsdn';
message_retail[1]='1 sdn gs dngsd njsdng fg nhfdngfgdmnsfngd sgn sng sn gsdnggdrg';
message_retail[2]='2 gs lasfl gas;flg as;lg alsjdf ahfg woiehg shdcg8y3trfg8ygsv2ge u yrfg ueyfvg uo5gsdfvogqwfouvgasd fgqowu gfowfgvsjdvg iwgc vlxkchgv lsd gv';
message_retail[3]='3 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad is nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo.';
message_retail[4]='4 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitationo laboris nisi ut aliquip ex ea commodo.';
message_retail[5]='5 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo.';
message_retail[6]='6 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labora. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ip ex ea commodo.';

var i_retail=0;

// rotates contents every x seconds
rotateContent_retail=function(){
var container_retail=document.getElementById('retail_div');
i_retail++;
if(i_retail==message_retail.length){i_retail=0}
container_retail.innerHTML=message_retail[i_retail];
this.timeout = setTimeout('rotateContent_retail()', 5*1000);
}

// loads global functions
loadGlobalFunctions_retail=function(){
// execute rotateContent function
rotateContent_retail();
}
// execute code once page is loaded
window.onload=loadGlobalFunctions_retail;

function nextItem() {
var container_retail=document.getElementById('retail_div');
clearTimeout(rotateContent_retail());
i_retail++;
if(i_retail==message_retail.length){i_retail=0}
container_retail.innerHTML=message_retail[i_retail];
}

function prevItem() {
var container_retail=document.getElementById('retail_div');
clearTimeout(rotateContent_retail());
i_retail--;
if(i_retail < 0){i_retail=message_retail.length - 1}
container_retail.innerHTML=message_retail[i_retail];
}
</script>

</head>
<body>

            <div id="retail_div" name="retail_div"></div><br />
            <a href="#" onclick="nextItem(); return false;">next item</a>

</body>
</html>

___

b0lsc0tt

The problem is your script tag. The type value is wrong. It should be text/javascript instead of javascript (see below).

<script type="text/javascript">

Let me know how that works.

bol

dirklance

ASKER

hi.

http://kccrossroads.org/new/content_rotator.html

3 issues:

1. i can't get the prevItem() to work?
2. the nextItem() calls every other element in the array
3. the auto rotate will freak out and cycle through the entire array every once and a while?

thanks,

* points raised. thank u

b0lsc0tt

Thanks for recognizing the extra work by increasing the points. That was very considerate.

OK. Hopefully all of the problems are related to this one issue. The settimeout and cleartimeout lines need to be changed. I will show you the new line but let me know if you have a question putting them in your code. In the function that sets the timeout use ...

t = setTimeout('rotateContent_retail()', 5*1000);

Then in the functions (2 of them) to cleartimeout use ...

clearTimeout(t);

In my tests all of the issues disappeared after that correction. Let me know how it works or if you have a question.

bol

dirklance

ASKER

that did fix all issues.

my last problem is that i have 3 divs that i need to cycle content through. i modified the script like:

__

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>

<script type="text/javascript">
// defines messages array
var message_retail=new Array();
message_retail[0]='0 dfngdfngdfngdfngsngsdngsngsdn';
message_retail[1]='1 sdn gs dngsd njsdng fg nhfdngfgdmnsfngd sgn sng sn gsdnggdrg';
message_retail[2]='2 gs lasfl gas;flg as;lg alsjdf ahfg woiehg shdcg8y3trfg8ygsv2ge u yrfg ueyfvg uo5gsd';
message_retail[3]='3 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor in';
message_retail[4]='4 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididun';
message_retail[5]='5 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididu';
message_retail[6]='6 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempo';

var i_retail=0;

// rotates contents every x seconds
rotateContent_retail=function(){
var container_retail=document.getElementById('retail_div');
i_retail++;
if(i_retail==message_retail.length){i_retail=0}
container_retail.innerHTML=message_retail[i_retail];
t_retail = setTimeout('rotateContent_retail()', 30*1000);
}

// loads global functions
loadGlobalFunctions_retail=function(){
// execute rotateContent function
rotateContent_retail();
}
// execute code once page is loaded
window.onload=loadGlobalFunctions_retail;

function retail_nextItem() {
var container_retail=document.getElementById('retail_div');
clearTimeout(t_retail);
i_retail++;
if(i_retail==message_retail.length){i_retail=0}
container_retail.innerHTML=message_retail[i_retail];
}

function retail_prevItem() {
var container_retail=document.getElementById('retail_div');
clearTimeout(t_retail);
i_retail--;
if(i_retail < 0){i_retail=message_retail.length - 1}
container_retail.innerHTML=message_retail[i_retail];
}

// start artist div

var message_artist=new Array();
message_artist[0]='0 dfngdfngdfngdfngsngsdngsngsdn';
message_artist[1]='1 sdn gs dngsd njsdng fg nhfdngfgdmnsfngd sgn sng sn gsdnggdrg';
message_artist[2]='2 gs lasfl gas;flg as;lg alsjdf ahfg woiehg shdcg8y3trfg8ygsv2ge u yrfg ueyfvg uo5gsd';
message_artist[3]='3 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor in';
message_artist[4]='4 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididun';
message_artist[5]='5 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididu';
message_artist[6]='6 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempo';

var i_artist=0;

// rotates contents every x seconds
rotateContent_artist=function(){
var container_artist=document.getElementById('artist_div');
i_artist++;
if(i_artist==message_artist.length){i_artist=0}
container_artist.innerHTML=message_artist[i_artist];
t_artist = setTimeout('rotateContent_artist()', 30*1000);
}

// loads global functions
loadGlobalFunctions_artist=function(){
// execute rotateContent function
rotateContent_artist();
}
// execute code once page is loaded
window.onload=loadGlobalFunctions_artist;

function artist_nextItem() {
var container_artist=document.getElementById('artist_div');
clearTimeout(t_artist);
i_artist++;
if(i_artist==message_artist.length){i_artist=0}
container_artist.innerHTML=message_artist[i_artist];
}

function artist_prevItem() {
var container_artist=document.getElementById('artist_div');
clearTimeout(t_artist);
i_artist--;
if(i_artist < 0){i_artist=message_artist.length - 1}
container_artist.innerHTML=message_artist[i_artist];
}

// end artist div

// start gallery

var message_gallery=new Array();
message_gallery[0]='0 dfngdfngdfngdfngsngsdngsngsdn';
message_gallery[1]='1 sdn gs dngsd njsdng fg nhfdngfgdmnsfngd sgn sng sn gsdnggdrg';
message_gallery[2]='2 gs lasfl gas;flg as;lg alsjdf ahfg woiehg shdcg8y3trfg8ygsv2ge u yrfg ueyfvg uo5gsd';
message_gallery[3]='3 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor in';
message_gallery[4]='4 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididun';
message_gallery[5]='5 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididu';
message_gallery[6]='6 Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempo';

var i_gallery=0;

// rotates contents every x seconds
rotateContent_gallery=function(){
var container_gallery=document.getElementById('gallery_div');
i_gallery++;
if(i_gallery==message_gallery.length){i_gallery=0}
container_gallery.innerHTML=message_gallery[i_gallery];
t_gallery = setTimeout('rotateContent_gallery()', 30*1000);
}

// loads global functions
loadGlobalFunctions_gallery=function(){
// execute rotateContent function
rotateContent_gallery();
}
// execute code once page is loaded
window.onload=loadGlobalFunctions_gallery;

function gallery_nextItem() {
var container_gallery=document.getElementById('gallery_div');
clearTimeout(t_gallery);
i_gallery++;
if(i_gallery==message_gallery.length){i_gallery=0}
container_gallery.innerHTML=message_gallery[i_gallery];
}

function gallery_prevItem() {
var container_gallery=document.getElementById('gallery_div');
clearTimeout(t_gallery);
i_gallery--;
if(i_gallery < 0){i_gallery=message_gallery.length - 1}
container_gallery.innerHTML=message_gallery[i_gallery];
}

// end gallery div

</script>

</head>
<body>

            <div id="retail_div" name="retail_div"></div><br />
            <a href="javascript:void(0);" onclick="retail_prevItem(); return false;">prev item</a> | <a href="javascript:void(0);" onclick="retail_nextItem(); return false;">next item</a><br /><br /><br />

            <div id="gallery_div" name="gallery_div"></div><br />
            <a href="javascript:void(0);" onclick="gallery_prevItem(); return false;">prev item</a> | <a href="javascript:void(0);" onclick="gallery_nextItem(); return false;">next item</a><br /><br /><br />

            <div id="artist_div" name="artist_div"></div><br />
            <a href="javascript:void(0);" onclick="artist_prevItem(); return false;">prev item</a> | <a href="javascript:void(0);" onclick="artist_nextItem(); return false;">next item</a><br /><br /><br />

</body>
</html>
___

but the timeout seems to be giving me troubles. i change 't' to 't_DIVNAME' . the retail div still works but i looks like the global onload isn't firing for the two new ones.

points raised.

thanks,

dirklance

ASKER

http://kccrossroads.org/new/contentRotator.html

thanks,

dirklance

ASKER

oops sorry:

http://kccrossroads.org/new/content_rotator.html

b0lsc0tt

One problem with this new change is the window.onload. Each use will overwrite the previous one. I suggest you first remove each line and then change the body tag to ...

<body onload="loadGlobalFunctions_retail; loadGlobalFunctions_artist; loadGlobalFunctions_gallery;">

That will most likely fix the problem but is definitely at least one cause. Let me know if you have a question or how that works. If you still have a problem then let me know if there was a javascript error and what it is.

bol

b0lsc0tt

I'm glad that helped. Thanks for the additional points, the grade and the fun question.

bol

dirklance

ASKER

thanks again for all ur help.

hopefully this'll help someone out.