function showMenu(menuNumber, eventObj) {
	//alert(eventObj);
	hideAllMenus();
	var menuId = 'menu' + menuNumber;
	if(changeObjectVisibility(menuId, 'visible')) {
	var menuTitle = getStyleObject('menuTitle' + menuNumber);
	menuTitle.backgroundColor = '#ff9900';
	eventObj.cancelBubble = true;
	return true;
	} else {
	return false;
	}
}

var numMenus = 3;
function hideAllMenus() {
	for(counter = 1; counter <= numMenus; counter++) {
		changeObjectVisibility('menu' + counter, 'hidden');
		var menuTitle = getStyleObject('menuTitle' + counter);
		menuTitle.backgroundColor = '#000000';
	}
}

// ************************
// layer utility routines *
// ************************
function getStyleObject(objectId) {
    // cross-browser function to get an object's style object given its id
    if(document.getElementById && document.getElementById(objectId)) {
		// W3C DOM
		return document.getElementById(objectId).style;
    } else if (document.all && document.all(objectId)) {
		// MSIE 4 DOM
		return document.all(objectId).style;
    } else if (document.layers && document.layers[objectId]) {
		// NN 4 DOM.. note: this won't find nested layers
		return document.layers[objectId];
    } else {
		return false;
    }
} // getStyleObject

function changeObjectVisibility(objectId, newVisibility) {
    // get a reference to the cross-browser style object and make sure the object exists
    var styleObject = getStyleObject(objectId);
    if(styleObject) {
		styleObject.visibility = newVisibility;
		return true;
    } else {
		// we couldn't find the object, so we can't change its visibility
		return false;
    }
} // changeObjectVisibility

function moveObject(objectId, newXCoordinate, newYCoordinate) {
    // get a reference to the cross-browser style object and make sure the object exists
    var styleObject = getStyleObject(objectId);
    if(styleObject) {
		styleObject.left = newXCoordinate;
		styleObject.top = newYCoordinate;
		return true;
    } else {
		// we couldn't find the object, so we can't very well move it
		return false;
    }
} // moveObject
	
document.onclick = hideAllMenus;