/* This file handles the rollover effects of the main menu. */

userAgent = window.navigator.userAgent;
browserVers = parseInt(userAgent.charAt(userAgent.indexOf("/")+1),10);

function findElement(n,ly) {
    if (browserVers < 4)		return document[n];
    var curDoc = ly ? ly.document : document;
    var elem = curDoc[n];
    if (!elem) {
        for (var i=0;i<curDoc.layers.length;i++) {
            elem = findElement(n,curDoc.layers[i]);
            if (elem) return elem;
        }
    }
    return elem;
}

function newImage(arg) {
    if (document.images) {
        rslt = new Image();
        rslt.src = arg;
        return rslt;
    }
}

function changeImages() {
    if (document.images) {
        var img;
        for (var i=0; i<changeImages.arguments.length; i+=2) {
            img = null;
            if (document.layers) {
                img = findElement(changeImages.arguments[i],0);
            }
            else {
                img = document.images[changeImages.arguments[i]];
            }
            if (img) {
                img.src = changeImages.arguments[i+1];
            }
        }
    }
}

var preloadFlag = false;

function preloadImages() {
    if (document.images) {
        Button0_over = newImage("Grafik/Button0_over.gif");
        Button1_over = newImage("Grafik/Button1_over.gif");
        Button2_over = newImage("Grafik/Button2_over.gif");
        Button3_over = newImage("Grafik/Button3_over.gif");
        Button4_over = newImage("Grafik/Button4_over.gif");
        Button5_over = newImage("Grafik/Button5_over.gif");
        preloadFlag = true;
    }
}