README.md
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##<iron-localstorage>
Element access to Web Storage API (window.localStorage).
Keeps value
property in sync with localStorage.
Value is saved as json by default.
Usage:
ls-sample
will automatically save changes to its value.
<dom-module id="ls-sample">
<iron-localstorage name="my-app-storage"
value="{{cartoon}}"
on-iron-localstorage-load-empty="initializeDefaultCartoon"
></iron-localstorage>
</dom-module>
<script>
Polymer({
is: 'ls-sample',
properties: {
cartoon: {
type: Object
}
},
// initializes default if nothing has been stored
initializeDefaultCartoon: function() {
this.cartoon = {
name: "Mickey",
hasEars: true
}
},
// use path set api to propagate changes to localstorage
makeModifications: function() {
this.set('cartoon.name', "Minions");
this.set('cartoon.hasEars', false);
}
});
</script>
Tech notes:
value.*
is observed, and saved on modifications. You must use path change notifification methods such asset()
to modify value for changes to be observed.Set
auto-save-disabled
to prevent automatic saving.Value is saved as JSON by default.
To delete a key, set value to null
Element listens to StorageAPI storage
event, and will reload upon receiving it.
Warning: do not bind value to sub-properties until Polymer
bug 1550
is resolved. Local storage will be blown away.
<iron-localstorage value="{{foo.bar}}"
will cause data loss.