// show/hide layer script, Written by Philip Mackay, last modified 11/09/07
// takes a layer name, and a required state for that layer, either visible or hidden
// includes findLayer function

// Declare some global variables for browser detection, somewhat obselete now

var theAppName = navigator.appName;
var theAppVersion = navigator.appVersion;
var theAppVersionArray = theAppVersion.split(' ');
var theAppNumber;

if (theAppName == "Microsoft Internet Explorer") {
	var theAppNumberArray = theAppVersionArray[3].split(';');
	theAppNumber = theAppNumberArray[0];
	}
else
	theAppNumber = theAppVersionArray[0];

function showHide(layerName,changeInLayer)
	{
	var layerToChange;
	var changeInLayerFixed;

	// if the user has netscape 4, change 'visible' and 'hidden' to 'show' and 'hide'
	if(document.all || (theAppName == 'Netscape' && theAppNumber >= '5.0'))
		changeInLayerFixed = changeInLayer;
	else if(document.layers)
		{
		if(changeInLayer == 'visible')
			changeInLayerFixed = 'show';
		else if(changeInLayer == 'hidden')
			changeInLayerFixed = 'hide';
		}

	// get the layer object
	layerToChange = findLayer(layerName);

	// alter the visibility
	layerToChange.visibility = changeInLayerFixed;
	}


function findLayer(layerName)
	{
	var layerFound, layerString;
	
	if((document.getElementById) || (theAppName == 'Netscape' && theAppNumber >= '5.0')) // Check for Netscape 5+ browsers
		{
		layerFound = document.getElementById(layerName).style;
		}
	else if(document.layers) // Check for Netscape 4
		{
		layerString = 'document.layers[' + layerName + ']';
		layerFound = eval(layerString);
		}
	
	return layerFound;
	}