Add rerender method in TraitView

docs/modules/Traits.md

@@ -196,10 +196,29 @@ If you need to change some trait on your component you can update it wherever yo
 The trait is a simple property of the component so to get the complete list of current traits you can use this:
 
 ```js
-const traits = editor.getSelected().get('traits');
+const component = editor.getSelected(); // Component selected in canvas
+const traits = component.get('traits');
 traits.forEach(trait => console.log(trait.props()))
 ```
 
+In case you need a single one:
+
+```js
+const component = editor.getSelected();
+console.log(component.getTrait('type').props()); // Finds by the `name` of the trait
+```
+
+If you want, for example, updating some property of the trait, do this:
+
+```js
+// Let's update `options` of our `type` trait, defined in Input component
+const component = editor.getSelected();
+component.getTrait('type').set('options', [
+  { id: 'opt1', name: 'New option 1'},
+  { id: 'opt2', name: 'New option 2'},
+])
+```
+
 
 ## Define new Trait type
 

src/trait_manager/view/TraitSelectView.js

@@ -6,7 +6,7 @@ const $ = Backbone.$;
 
 export default TraitView.extend({
   init() {
-    this.listenTo(this.model, 'change:options', this.render);
+    this.listenTo(this.model, 'change:options', this.rerender);
   },
 
   templateInput() {

src/trait_manager/view/TraitView.js

@@ -215,6 +215,11 @@ export default Backbone.View.extend({
     return !this.model.get('noLabel');
   },
 
+  rerender() {
+    this.model.el = null;
+    this.render();
+  },
+
   render() {
     const { $el, pfx, ppfx, model, target } = this;
     const { type } = model.attributes;