JarCasting
<iron-localstorage>
Element access to Web Storage API (window.localStorage) by keeping value property in sync with localStorage.
Value is saved as json by default.
See: Documentation, Demo.
Usage
Installation
npm install --save @polymer/iron-localstorage
In an html file
<html>
<body>
<iron-localstorage name="my-app-storage"></iron-localstorage>
<script type="module">
import '@polymer/iron-localstorage/iron-localstorage.js';
const ls = document.querySelector('iron-localstorage');
// initializes default if nothing has been stored
function initializeDefaultCartoon() {
ls.value = {
name: "Mickey",
hasEars: true
};
}
ls.addEventListener(
'iron-local-storage-load-empty', initializeDefaultCartoon);
// use path set api to propagate changes to localstorage
function makeModifications() {
ls.set('value.name', "Minions");
ls.set('value.hasEars', false);
}
</script>
</body>
</html>
In a Polymer 3 element
import {PolymerElement, html} from '@polymer/polymer';
import '@polymer/iron-localstorage/iron-localstorage.js';
class SampleElement extends PolymerElement {
static get template() {
return html`
<iron-localstorage name="my-app-storage"
value="{{cartoon}}"
on-iron-localstorage-load-empty="initializeDefaultCartoon">
</iron-localstorage>
`;
}
static get properties() {
return {
cartoon: { type: Object },
}
}
// initializes default if nothing has been stored
initializeDefaultCartoon() {
this.cartoon = {
name: "Mickey",
hasEars: true
}
}
// use path set api to propagate changes to localstorage
makeModifications() {
this.set('cartoon.name', "Minions");
this.set('cartoon.hasEars', false);
}
}
customElements.define('sample-element', SampleElement);
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-localstorage
cd iron-localstorage
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
