//global variables that can be used by ALL the function son this page.
var inputs;
var imgFalse = 'graphics/chk_off.gif';
var imgTrue = 'graphics/chk_on.gif';

//this function runs when the page is loaded, put all your other onload stuff in here too.
function init() {
    replaceChecks();
}

function replaceChecks() {
    
    //get all the input fields on the page
    inputs = document.getElementsByTagName('input');

    //cycle trough the input fields
    for(var i=0; i < inputs.length; i++) {

        //check if the input is a checkbox
        if(inputs[i].getAttribute('type') == 'checkbox') {
            
            //create a new image
            var img = document.createElement('img');
            
            //check if the checkbox is checked
            if(inputs[i].checked) {
                img.src = imgTrue;
            } else {
                img.src = imgFalse;
            }

            //set image ID and onclick action
            img.id = 'checkImage'+i;
            //set image
            img.onclick = new Function('checkChange('+i+')');
            //place image in front of the checkbox
            inputs[i].parentNode.insertBefore(img, inputs[i]);
            
            //hide the checkbox
            inputs[i].style.display='none';
        }
    }
}

//change the checkbox status and the replacement image
function checkChange(i) {

    if(inputs[i].checked) {
        inputs[i].checked = '';
        document.getElementById('checkImage'+i).src=imgFalse;
    } else {
        inputs[i].checked = 'checked';
        document.getElementById('checkImage'+i).src=imgTrue;
    }
}

function initChecklist() {
	if (document.all && document.getElementById) {
	// Get all unordered lists
	var lists = document.getElementsByTagName("ul");
		for (i = 0; i < lists.length; i++) {
			var theList = lists[i];
			
				// Only work with those having the class "checklist"
				if (theList.className.indexOf("checklist") > -1) {
					var labels = theList.getElementsByTagName("label");
					
					// Assign event handlers to labels within
					for (var j = 0; j < labels.length; j++) {
						var theLabel = labels[j];
						theLabel.onmouseover = function() { this.className += " hover"; };
						theLabel.onmouseout = function() { this.className = this.className.replace(" hover", ""); };
					}
				}
			}
		}
	}

function uncheckAll(field)
{
for (i = 0; i < field.length; i++)
	field[i].checked = false ;
}