javascript - Displaying a dialog from within a Polymer component -

i've polymer component, inside of 1 of function want display dialog user. tried dialog-paper follows:

<template>   <link rel="stylesheet" href="../themes/the-graph-dark.css">   <link rel="stylesheet" href="../themes/the-graph-light.css">   <div id="svgcontainer"></div>   <paper-dialog heading="title dialog" id="dialog">     <p>lorem ipsum ....</p>     <p>id qui scripta ...</p>     <paper-button label="more info..." dismissive></paper-button>     <paper-button label="decline" affirmative></paper-button>     <paper-button label="accept" affirmative autofocus></paper-button>   </paper-dialog> </template> ... eventhandler: function(event) {   this.$.dialog.toggle();   console.log(event); },     

when try toggle dialog when eventhandler invoked nothing shown , uncaught typeerror: undefined not function.

what appropriate way display dialog within component?

something this

polymer({   that: this,   ready: function(){       addeventlistener('on-blabla-event', function(event){         that.$.dialog.toggle();         console.log(event);       });     } });