function showwin(i) {
    var winNode = $("#" + i)
    winNode.toggle();
}

$(document).ready( function () {
	$().checkbox({checked: "images/checked.png", unchecked: "images/unchecked.png"});
});

jQuery.fn.checkbox = function (opt) {
	$(":checkbox").hide().each( function () {
	
		$("<img>")
			.attr( {src: this.checked ? opt.checked : opt.unchecked } )
			.click( function() {
				var check = jQuery(this).next()[0].checked == true;
				$(this)
					.attr( { src: check ? opt.unchecked : opt.checked } )
					.next()[0].checked = !check;
			})
			.insertBefore(this);
	});
}