function addOption(sel, v, n)
{
	var newOpt = sel.appendChild(document.createElement('option'));
	newOpt.text = n;
	newOpt.value = v;
}

$(document).ready(function() {
    $('#filter_attr').change(function() {
        var data = { 'attribut_id' : $(this).val() };
        $.getJSON(window.location.pathname, data, function(json) {
            var select = $('#filter_val')[0];
            select.length = 1;
            for (var i=0; i<json.length; i++)
            {
                addOption(select, json[i].url, json[i].name);
            }
            select.disabled = false;
        });
    });
    
    $('#filter_val').change(function() {
        window.location = $(this).val();
    });
});