DHTML Lab: Scrollbars for Netscape Navigator Layers - The Complete Code - dhtmlab.com

Scrollbars for Navigator 4 LAYERs, Part I
SPECIAL EDITION; the director's cut

The Hard-Coded HTML

<LAYER ID=elCont TOP=30 LEFT=30 WIDTH=400 BGCOLOR=black CLIP=400,200>
  <LAYER ID=elMain SRC="raven.html" onLoad="initScroll()" TOP=2 LEFT=4
   WIDTH=376 BGCOLOR=white CLIP=-2,0,394,196></LAYER>
  <LAYER ID=elScroll LEFT=382 TOP=2 WIDTH=16 CLIP=16,196 VISIBILITY=HIDE>
    <IMG SRC="butTu.gif" WIDTH=16 HEIGHT=16 BORDER=0 HSPACE=0 VSPACE=0>
    <LAYER ID=elBGcol LEFT=0 TOP=16 CLIP=16,250 BACKGROUND="barBgBl.gif"></LAYER>
    <LAYER ID=elBG LEFT=0 TOP=16 CLIP=16,250 BACKGROUND="barBg.gif"></LAYER>
    <LAYER ID=elThumb LEFT=0 TOP=16 WIDTH=16 CLIP=16,100 BACKGROUND="tmbBg.gif">
      <IMG SRC="tmbTop.gif" WIDTH=16 HEIGHT=2 BORDER=0 HSPACE=0 VSPACE=0 ALIGN=RIGHT>
      <LAYER ID=elThumbBot LEFT=0 TOP=98 WIDTH=16 CLIP=16,2>
        <IMG SRC="tmbBot.gif" WIDTH=16 HEIGHT=2 BORDER=0 HSPACE=0 VSPACE=0 ALIGN=RIGHT>
      </LAYER>
    </LAYER>
    <LAYER ID=elButtonBot LEFT=0 TOP=180 WIDTH=16 CLIP=16,16>
      <IMG SRC="butBu.gif" WIDTH=16 HEIGHT=16 HSPACE=0 BORDER=0>
    </LAYER>
  </LAYER>
</LAYER>

The Images

All the images used and the complete script are available for download in zip format.

The Script

The complete script and the images used are available for download in zip format.

origWidth = innerWidth;
origHeight = innerHeight;
function reDo() {
    if (innerWidth != origWidth || innerHeight != origHeight)
        location.reload();
}
onresize = reDo;
arImLoad = ["barBg","barBgBl","bg","bgBl",
            "butBd","butBu","butTd","butTu",
            "tmbBg","tmbBgL","tmbBot","tmbTop"];
arImList = [];
for (counter in arImLoad) {
    arImList[counter] = new Image();
    arImList[counter].src = arImLoad[counter] + ".gif";
}
docIncr = 8;
barWidth = 16;
thumbMinHeight = 10;
origInt = 500;
repeatInt = 50;
initTimer = null;
scrollTimer = null;
bgTimer = null;
thumbTimer = null;
curY = null;
butImage = null;
pageLoaded = false;
onload = initScroll;
function initScroll(){
    if (!pageLoaded) {pageLoaded=true;return}        
    makeScroll();
}
function makeScroll(){
    elMain =  document.elCont.document.elMain;
    elScroll = document.elCont.document.elScroll;
    if (elMain.origTop) elMain.top = elMain.origTop;
    elMain.origTop = elMain.top;
    elMain.clip.top = 0;
    if (elMain.origHeight) elMain.clip.height = elMain.origHeight;
    elMain.origHeight = elMain.clip.height;
    docHeight = elMain.document.height;
    lyrHeight = elMain.clip.height;
    if (docHeight <= lyrHeight){
        elScroll.visibility = "hide";
        return;
    }
    elThumb = elScroll.document.elThumb;
    elThumb.top = barWidth;
    elThumbBot = elThumb.document.elThumbBot;
    elvBarHeight = elScroll.clip.height - (barWidth*2);
    thumbHeight = Math.max((lyrHeight*elvBarHeight)/docHeight,thumbMinHeight)
    elThumb.clip.height = thumbHeight;
    elThumbBot.top = thumbHeight - elThumbBot.clip.height;
    thumbMaxTop = (elvBarHeight + barWidth) - thumbHeight;
    docToTravel = docHeight - lyrHeight;
    scrToTravel = elvBarHeight - thumbHeight;
    scrPixels = scrToTravel/docToTravel;
    docPixels = docToTravel/scrToTravel;
    upImage = elScroll.document.images[0];
    elButtonBot = elScroll.document.elButtonBot;
    downImage = elButtonBot.document.images[0];
    upImage.direction = 0;
    downImage.direction = 1;
    upImage.onmousedown = butDown;        
    downImage.onmousedown = butDown;
    elThumb.captureEvents(Event.MOUSEDOWN); 
    elThumb.onmousedown = thumbDown;
    elBG = elScroll.document.elBG;
    elBGcol = elScroll.document.elBGcol;
    elBG.captureEvents(Event.MOUSEDOWN);
    elBG.onmousedown = bgDown;
    elScroll.visibility="show";
}
function clearTimers() {
    clearTimeout(initTimer);
    clearInterval(scrollTimer);
    initTimer = scrollTimer = null;
    clearTimeout(bgTimer);
    clearInterval(thumbTimer);
    bgTimer = thumbTimer = null;
}
function butDown(e){
    butImage = e.target;
    dir = butImage.direction
    butImage.origSrc = butImage.src;
    butImage.src = (dir) ? "butBd.gif" : "butTd.gif";
    butImage.onmouseout = butOut;
    captureEvents(Event.MOUSEUP)
    onmouseup = butUp;
    butMove(dir);
    if(e.type=="mousedown") initTimer = setTimeout("scrollTimer = setInterval(butMove,repeatInt,dir)",origInt);
    else scrollTimer = setInterval(butMove,repeatInt,dir);
    return false;
}
function butMove(dir) {
    if ((dir && elMain.clip.top==docToTravel) || (!dir && elMain.clip.top==0)) {clearTimers();return}
    elMain.top = (dir) ? Math.max(elMain.top-docIncr,elMain.origTop-docToTravel) : Math.min(elMain.top+docIncr,elMain.origTop);
    elMain.clip.top = (dir) ? Math.min(elMain.clip.top+docIncr,docToTravel) : Math.max(elMain.clip.top-docIncr,0) ;
    elMain.clip.height = elMain.origHeight;
    elThumb.top = Math.min(Math.max(barWidth + (scrPixels*elMain.clip.top),barWidth),thumbMaxTop);
}
function butOut(){
    clearTimers();
    butImage.src = butImage.origSrc;
    butImage.onmouseover = butDown;
}
function butUp(){
    clearTimers();
    butImage.src = butImage.origSrc;
    butImage.onmouseout = null;
    butImage.onmouseover = null;
    releaseEvents(Event.MOUSEUP);
    return false;
}
function thumbDown(e) {
    curY = e.pageY;
    captureEvents(Event.MOUSEMOVE|Event.MOUSEUP); 
    onmousemove = thumbMove;
    onmouseup = thumbUp;
    return false;
}
function thumbMove(e) {
    difY = e.pageY - curY;
    elThumb.top = Math.min(Math.max(elThumb.top+difY,barWidth),thumbMaxTop);
    docAlign();
    curY = e.pageY;
}
function thumbUp() {
    releaseEvents(Event.MOUSEMOVE|Event.MOUSEUP); 
}
function docAlign(){
    thumbDiff = elThumb.top - barWidth;
    elMain.top = elMain.origTop - (thumbDiff*docPixels);
    elMain.clip.top = (thumbDiff*docPixels);
    elMain.clip.height = elMain.origHeight;
}
function bgDown(e){
    dir = (e.pageY < elThumb.pageY) ? -1 : 1;
    captureEvents(Event.MOUSEUP);
    onmouseup = bgUp;
    bgMove(e);
    ev = e;
    bgTimer = setTimeout("thumbTimer = setInterval(bgMove,repeatInt,ev)",origInt);
    return false;
}
function bgMove(e){
    if (e.pageY > elThumb.pageY && e.pageY <= elThumb.pageY+elThumb.clip.height) {bgUp();return}
    elThumb.top = Math.min(Math.max(elThumb.top + elThumb.clip.height * dir,barWidth),thumbMaxTop);
    elBGcol.top = (dir==1) ? elThumb.top : barWidth;
    elBGcol.clip.bottom = (dir==1) ? scrToTravel : elThumb.top-barWidth;
    elBGcol.moveAbove(elBG);
    docAlign();
}
function bgUp(){
    clearTimers();
    releaseEvents(Event.MOUSEUP);
    elBG.moveAbove(elBGcol);
    return false;
}
function loadnew(num){
    switch (num) {
        case 0:
            newFile = "oscar.html";
            break;
        case 1:
            newFile = "raven.html";
            break;
        case 2:
            newFile = "usher.html";
            break;
    }
    
    elMain.load(newFile,376)
}

// end

Produced by Peter Belesis and

URL: https://www.webreference.com/dhtml/column23/allCode.html