How to access attributes or methods of polymer element instances

Question

I have defined a new polymer Element.

<polymer-element name="m-test">
  <template>
  ...
  </template>
  <script type="application/dart" src="m-test.dart"></script>
</polymer-element>

@CustomTag('m-test')
class Mtest extends PolymerElement {
  @observable int myAttr = 0;
  ...  
void myMethod()

How can I access the attribute myAttr or call the method myMethod for an instance of this element in my main dart program.

<m-test id="mt1"></m-test>
<m-test id="mt2"></m-test>

Answer 1

You can access your attributes in markup

<m-test id="mt1" my-attr="5"></m-test>

or in code

querySelector('#mt1').myAttr = 5; // produces a warning in the editor
querySelector('#mt1').myMethod(5); // - " -
(querySelector('#mt1') as Mtest).myAttr = 5; // may fail at runtime due to bug https://code.google.com/p/dart/issues/detail?id=15953
(querySelector('#mt1') as Mtest).myMethod(5); // - " -

you can also access event handlers declaratively

void clickHandler(event, detail, target) {
  // handle event
}

<polymer-element name="m-test">
  <template>
    <button on-click="{{clickHandler}}">{{myAttr}}</button> // caption from myAttr
  </template>
  <script type="application/dart" src="m-test.dart"></script>
</polymer-element>