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javascriptslideshowplaybackpauserewind

Javascript slideshow - Add next/forward and previous/rewind

I have this javascript slideshow which is working fine with the pause/play option:

<html>
<head>
<title>Simple Javascript Slideshow</title>
<script type="text/javascript">
var i = 0, imgsrc = new Array(), preload = new Array();
imgsrc[0]="photos/image1.png";
imgsrc[1]="photos/image2.png";
imgsrc[2]="photos/image3.png";
for (var j=0;j<imgsrc.length;j++)
{
preload[j] = new Image;
preload[j].src = imgsrc[j];
}
function mode(param)
{
smode=param;
}
function startSlideshow()
{
if(smode=="play")
{
document.getElementById("play").disabled="disabled";
document.getElementById("pause").disabled="";
document.getElementById("stop").disabled="";
document.getElementById("slideshow").src=imgsrc[i];
i++;
setTimeout("startSlideshow()",1000);
}
else if(smode=="pause")
{
document.getElementById("pause").disabled="disabled";
document.getElementById("play").disabled="";
document.getElementById("play").value="Resume";
}
else if(smode=="stop")
{
document.getElementById("play").disabled="";
document.getElementById("play").value="Play";
document.getElementById("pause").disabled="disabled";
document.getElementById("stop").disabled="disabled";
document.getElementById("slideshow").src=imgsrc[0];
i=0;
}
if(i==imgsrc.length)
{
i=0;
}
}
</script>
</head>
<body>
<img id="slideshow" src="photos/Aanimation-ir001.png" />
<br />
<input id="play" type="button" value="Play" onclick="mode('play');startSlideshow();" />
<input id="pause" type="button" value="Pause" disabled="disabled" 
onclick="mode('pause');startSlideshow();" />
<input id="stop" type="button" value="Stop" disabled="disabled" 
onclick="mode('stop');startSlideshow();" />
</body>
</html>

It would be great to have a rewind/forward (next/previous image) option to use with the pause-option.

Is that possible?

Kind Regards

Solution

  • You should be able to figure it out with your current code.

    Here are some hints :

    The image currently displayed is defined by this :

    document.getElementById("slideshow").src=imgsrc[i];

    If the currently displayed image has index i, what index does the next one have ? What about the previous one ?

    Once you have solved this, you must bind your new function (or new case of your existing function) to your HTML markup, like you have done here :

    <input id="next" type="button" value="Next" onclick="mode('next');" />

    As a side note, you should pay attention to what happens if you're displaying the last (or first) image and press next (or previous).

    Hope that helps.