polygerrit-ui/app/samples/bind-parameters.html

<dom-module id="bind-parameters">
  <script>
    Gerrit.install(plugin => {
      plugin.registerCustomComponent(
          'change-view-integration', 'my-bind-sample');
    });
  </script>
</dom-module>

<dom-module id="my-bind-sample">
  <template>
    Template example: Patchset number [[revision._number]]. <br/>
    Computed example: [[computedExample]].
  </template>
  <script>
    Polymer({
      is: 'my-bind-sample',
      _legacyUndefinedCheck: true,
      properties: {
        computedExample: {
          type: String,
          computed: '_computeExample(revision._number)',
        },
      },
      attached() {
        this.plugin.attributeHelper(this).bind(
            'revision', this._onRevisionChanged.bind(this));
      },
      _computeExample(value) {
        if (!value) { return '(empty)'; }
        return `(patchset ${value} selected)`;
      },
      _onRevisionChanged(value) {
        console.log(`(attributeHelper.bind) revision number: ${value._number}`);
      },
    });
  </script>
</dom-module>