delite/CustomElement
delite/CustomElement is a base class for non-visual custom elements, such as an element representing a data store.
It also serves as the base class for delite/Widget.
Behind the scenes, delite/CustomElement provides many of the features mentioned in the
Introduction to delite and custom elements. In particular,
it parses attributes in declarative markup, for example converting:
<my-widget numProp="123"></my-widget>
into:
myWidget.numProp = 123;
The initialization methods in delite/CustomElement correspond to the function names from the
Custom Elements specification, specifically createdCallback() and attachedCallback().
delite/CustomElement does not provide the attributeChangedCallback(), but you can
find out when properties change by declaring the properties in your element's prototype, and then reacting to changes
in refreshRendering().
Finally, CustomElement provides common methods like on() and destroy(), but
it does not provide the delite/Widget specific lifecycle methods
like render() and postRender().
