// JavaScript Document

 

// gives up and down scroll buttons to images, spans, ... named up_name, down_name, respectively.

// will keep the default scroll_box's style overflow if it encounters errors (so make overflow: auto;)

 

// usage: put this after the scrollbox div:  var div_scroll1 = new TextScroll('div_scroll1', 'scroll_box');

 

function TextScroll(scrollname, div_name, up_name, down_name)

{

    this.div_name = div_name;

    this.name = scrollname;

    this.scrollCursor = 0;

    this.speed = 5;

    this.timeoutID = 0;

    this.div_obj = null;

    this.up_name = up_name;

    this.dn_name = down_name;

 

{

        if (document.getElementById) {

            div_obj = document.getElementById(this.div_name);

            if (div_obj) {

                this.div_obj = div_obj;

                this.div_obj.style.overflow = 'hidden';

            }

            div_up_obj = document.getElementById(this.up_name);

            div_dn_obj = document.getElementById(this.dn_name);

            if (div_up_obj && div_dn_obj) {

                 div_up_obj.onmouseover = function() { eval(scrollname + ".scrollUp();") };

                                                                                                                                 div_up_obj.onmouseout = function() { eval(scrollname + ".stopScroll();") };

                                                                                                                                 div_dn_obj.onmouseover = function() { eval(scrollname + ".scrollDown();") };

                                                                                                                                 div_dn_obj.onmouseout = function() { eval(scrollname + ".stopScroll();") };

            }

        }

    }

 

this.stopScroll = function() {

        clearTimeout(this.timeoutID);

    }

 

this.scrollUp = function() {

        if (this.div_obj) {

            this.scrollCursor = (this.scrollCursor - this.speed) < 0 ? 0 : this.scrollCursor - this.speed;

            this.div_obj.scrollTop = this.scrollCursor;

            this.timeoutID = setTimeout(this.name + ".scrollUp()", 60);

        }

    }

 

this.scrollDown = function() {

                if (this.div_obj) {

                                this.scrollCursor += this.speed;

                                this.div_obj.scrollTop = this.scrollCursor;

                                if (this.div_obj.scrollTop == this.scrollCursor) {

                                                this.timeoutID = setTimeout(this.name + ".scrollDown()", 60);

                                } else {

                                                this.scrollCursor = this.div_obj.scrollTop;

                                }

                }

}

 

this.resetScroll = function() {

        if (this.div_obj) {

            this.div_obj.scrollTop = 0;

            this.scrollCursor = 0;

        }

    }

}