Javascript example

by vi161

HTML

<!-- Left Button. -->
<div style="float:left;">
  <!-- (1) Whilst it's pressed, increment the scroll. When we release, clear the timer to stop recursive scroll calls. -->
   <input type="button" value="«" style="height: 100px;" onmousedown="scroll('scroller',3, 10);" onmouseup="clearTimeout(TIMER_SCROLL);"/>
</div>
<!-- Contents to scroll. -->
<div id="scroller" style="float: left; width: 300px; height: 100px; overflow: scroll;">
  <!-- <3 -->
  <img src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png?v=9c558ec15d8a" alt="image large" style="height: 100px" />
    <img src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png?v=9c558ec15d8a" alt="image large" style="height: 100px" />
      <img src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png?v=9c558ec15d8a" alt="image large" style="height: 100px" />
</div>
<!-- Right Button. -->
<div style="float:left;">
  <!-- As (1). (Use a negative value of 'd' to decrease the scroll.) -->
  <input type="button" value="»" style="height: 100px;" onmousedown="scroll('scroller',-3, 10);" onmouseup="clearTimeout(TIMER_SCROLL);"/>
</div>

JavaScript

// Declare the Shared Timer.
var TIMER_SCROLL;
/** 
Scroll function. 
@param id  Unique id of element to scroll.
@param d   Amount of pixels to scroll per sleep.
@param del Size of the sleep (ms).*/
function scroll(id, d, del){
	// Scroll the element.
  document.getElementById(id).scrollLeft += d;
  // Perform a delay before recursing this function again.
  TIMER_SCROLL = setTimeout("scroll('"+id+"',"+d+", "+del+");", del);
}