first html and dart files
define HTML template for the custom element
create a Dart class that extends a Polymer Element
add project dependencies, but they fail to be installed. do I need to update my dart sdk?
Dart SDK updated to 1.7.2. It fixes the problem with the polymer dependency
Implement the HTML template for the custom element. Uses data binding and declarative event handling
Implement custom element behaviour in .dart file. Define a class, extend from PolymerElement, named constructor 'created()', define data binding variables, event handlers, and override some life-cycle methods
Implement logic in the overriden method 'attached()', where a reference to each button is created and stop and reset buttons are disabled