JSPM – @polymer/iron-checked-element-behavior@3.0.0-pre.26

Package Exports

@polymer/iron-checked-element-behavior
@polymer/iron-checked-element-behavior/iron-checked-element-behavior.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (@polymer/iron-checked-element-behavior) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

IronCheckedElementBehavior

Use IronCheckedElementBehavior to implement a custom element that has a checked property, which can be used for validation if the element is also required. Element instances implementing this behavior will also be registered for use in an iron-form element.

See: Documentation, Demo.

Usage

Installation

npm install --save @polymer/iron-checked-element-behavior

In a Polymer 3 element

import {PolymerElement} from '@polymer/polymer/polymer-element.js';
import {mixinBehaviors} from '@polymer/polymer/lib/legacy/class.js';
import {html} from '@polymer/polymer/lib/utils/html-tag.js';

import {IronCheckedElementBehavior} from '../iron-checked-element-behavior.js';

class SimpleCheckbox extends mixinBehaviors(IronCheckedElementBehavior, PolymerElement) {
  static get template() {
    return html`
      <style>
        :host([invalid]) {
          color: red;
        }
      </style>

      <button on-click="_checkValidity">validate</button>
      <input type="checkbox" id="checkbox" checked="{{checked::input}}">
      <span id="labelText">{{label}}</span>
    `;
  }

  static get properties() {
    return {label: {type: String, value: 'not validated'}};
  }

  _checkValidity() {
    this.validate();
    this.label = this.invalid ? 'is invalid' : 'is valid';
  }
}

customElements.define('simple-checkbox', SimpleCheckbox);

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-checked-element-behavior
cd iron-checked-element-behavior
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