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Polymer 2.0 - How to use Iron Ajax?

I am trying to link local properties.jsonand trying to create dynamic elements, but the problem is that I am not getting any console errors and not seeing JSON in the user interface.

I did not find a Polymer 2.0 example to use <iron-ajax>, but I found only for Polymer 1.0.

Here is the code I tried:

polymer-input.html

<link rel="import" href="https://www.polymer-project.org/0.5/components/polymer/polymer-element.html">
<link rel="import" href="https://www.polymer-project.org/0.5/components/iron-ajax/iron-ajax.html">

<dom-module id="polymer-app">
  <template>
    <style>
      :host {
        display: block;
      }
    </style>
    <iron-ajax auto="" url="properties.json" handle-as="json" last-response="{{ajaxResponse}}"></iron-ajax>
    <template is="dom-repeat" items="[[ajaxResponse]]">
      <span>[[item.name]]</span>
    </template>
    <h2>Hello [[prop1]]!..[[ajaxResponse]]</h2>

  </template>

  <script>
    /**
     * @customElement
     * @polymer
     */
    class PolymerApp extends Polymer.Element {
      static get is() { return 'polymer-app'; }
      static get properties() {
        return {
          prop1: {
            type: String,
            value: 'polymer-app'
          }
        };
      }
    }

    window.customElements.define(PolymerApp.is, PolymerApp);
  </script>
</dom-module>

index.html

<!doctype html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, minimum-scale=1, initial-scale=1, user-scalable=yes">

    <title>polymer</title>
    <meta name="description" content="custom ele">


    <script src="https://www.polymer-project.org/0.5/components/webcomponentsjs/webcomponents-loader.js"></script>

    <link rel="import" href="polymer-app/polymer-app.html">
    <link rel="import" href="polymer-input/polymer-input.html">
  </head>
  <body>
    <polymer-app></polymer-app>
   </body>
</html>

properties.json:

{
  {
    name:"Name",
    type:"string",
    size:20
  },
  {
    name:"Age",
    type:"number",
    size:20
  }
}

I get below output instead of json data properties enter image description here

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1 answer

The first problem is that your demo uses the base URL for Polymer 0.5, while your code uses the Polymer 2.0 syntax. That is, this code:

<link rel="import" href="https://www.polymer-project.org/0.5/components/polymer/polymer-element.html">
<link rel="import" href="https://www.polymer-project.org/0.5/components/iron-ajax/iron-ajax.html">

... should be something like this:

<link rel="import" href="https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/polymer/polymer-element.html">
<link rel="import" href="https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/iron-ajax/iron-ajax.html">

-, properties.json JSON. , ; . , JSON.parse() . :

{
  {
    name:"Name",
    type:"string",
    size:20
  },
  {
    name:"Age",
    type:"number",
    size:20
  }
}

... :

[
  {
    "name":"Name",
    "type":"string",
    "size":20
  },
  {
    "name":"Age",
    "type":"number",
    "size":20
  }
]

-, , <iron-ajax> <iron-ajax>.lastResponse null, <iron-ajax>.handleAs - json, JSON. JSON properties.json , lastResponse null, .

Polymer 2 <iron-ajax> ( ) : http://plnkr.co/edit/2mpJd1b0UF5FqAr2BOxL?p=preview

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