function updateLayerVisibility() { var inputs = dojo.query(".list_item"), input; visible = []; for (var i=0, il=inputs.length; i<il; i++) { if (inputs.checked) { visible.push(inputs.value); } } //if there aren't any layers visible set the array value to = -1 if(visible.length === 0){ visible.push(-1); } //alert(visible); layer.setVisibleLayers(visible); }