An input with data binding
Latest commit a44acd4 Sep 14, 2018

README.md

Published on NPM Build status Published on webcomponents.org

<iron-input>

<iron-input> adds two-way binding and custom validators using Polymer.IronValidatorBehavior to <input>.

See: Documentation, Demo.

Usage

Installation

npm install --save @polymer/iron-input

In an html file

<html>
  <head>
    <script type="module">
      import '@polymer/iron-input/iron-input.js';
    </script>
  </head>
  <body>
    <iron-input>
      <input>
    </iron-input>
  </body>
</html>

In a Polymer 3 element

import {PolymerElement, html} from '@polymer/polymer';
import '@polymer/iron-input/iron-input.js';

class SampleElement extends PolymerElement {
  static get template() {
    return html`
      <iron-input>
        <input>
      </iron-input>
    `;
  }
}
customElements.define('sample-element', SampleElement);

Two-way binding

By default you can only get notified of changes to an input's value due to user input:

<input value="{{myValue::input}}">

iron-input adds the bind-value property that mirrors the value property, and can be used for two-way data binding. bind-value will notify if it is changed either by user input or by script.

<iron-input bind-value="{{bindValue}}">
  <input value="{{value::input}}">
</iron-input>

Custom validators

You can use custom validators that implement Polymer.IronValidatorBehavior with <iron-input>.

<iron-input auto-validate validator="my-custom-validator">
  <input placeholder="only 'cat' is valid">
 </iron-input>

Stopping invalid input

It may be desirable to only allow users to enter certain characters. You can use the prevent-invalid-input and allowed-pattern attributes together to accomplish this. This feature is separate from validation, and allowed-pattern does not affect how the input is validated.

<!-- only allow characters that match [0-9] -->
<iron-input allowed-pattern="[0-9]">
  <input pattern="\d{5}">
</iron-input>

Contributing

If you want to send a PR to this element, here are the instructions for running the tests and demo locally:

Installation

git clone https://github.com/PolymerElements/iron-input
cd iron-input
npm install
npm install -g polymer-cli

Running the demo locally

polymer serve --npm
open http://127.0.0.1:<port>/demo/

Running the tests

polymer test --npm