Jamal,
Here is one way:
view.when(function() {
var layerList = new LayerList({
view: view,
});
setTimeout(function() {
view.layerViews.map(function(item){
item.watch('visible', function(visible){
console.info(visible, item.layer.title);
}, item.layer.title);
});
}, 500);
view.ui.add(layerList, "top-right");
});