[](https://www.npmjs.com/package/@polymer/iron-selector) [](https://travis-ci.org/PolymerElements/iron-selector) [](https://webcomponents.org/element/@polymer/iron-selector) ## <iron-selector>, `IronSelectableBehavior`, `IronMultiSelectableBehavior` `iron-selector` is an element which can be used to manage a list of elements that can be selected. Tapping on the item will make the item selected. The `selected` indicates which item is being selected. The default is to use the index of the item. `iron-selector`'s functionality is entirely defined by `IronMultiSelectableBehavior`. `IronSelectableBehavior` gives an element the concept of a selected child element. By default, the element will select one of its selectable children when a ['tap' event](https://www.polymer-project.org/3.0/docs/devguide/gesture-events#gesture-event-types) (synthesized by Polymer, roughly 'click') is dispatched to it. `IronSelectableBehavior` lets you ... - decide which children should be considered selectable (`selectable`), - retrieve the currently selected element (`selectedItem`) and all elements in the selectable set (`items`), - change the selection (`select`, `selectNext`, etc.), - decide how selected elements are modified to indicate their selected state (`selectedClass`, `selectedAttribute`), ... among other things. `IronMultiSelectableBehavior` includes all the features of `IronSelectableBehavior` as well as a `multi` property, which can be set to `true` to indicate that the element can have multiple selected child elements. It also includes the `selectedItems` and `selectedValues` properties for working with arrays of selectable elements and their corresponding values (`multi` is `true`) - similar to the single-item versions provided by `IronSelectableBehavior`: `selectedItem` and `selected`. See: [Documentation](https://www.webcomponents.org/element/@polymer/iron-selector), [Demo](https://www.webcomponents.org/element/@polymer/iron-selector/demo/demo/index.html). ## Usage ### Installation ``` npm install --save @polymer/iron-selector ``` ### In an HTML file ```html

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``` ### In a Polymer 3 element ```js import {PolymerElement} from '@polymer/polymer/polymer-element.js'; import {html} from '@polymer/polymer/lib/utils/html-tag.js'; import '@polymer/iron-selector/iron-selector.js'; class ExampleElement extends PolymerElement { static get template() { return html`

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`; } } customElements.define('example-element', ExampleElement); ``` ## Contributing If you want to send a PR to this element, here are the instructions for running the tests and demo locally: ### Installation ```sh git clone https://github.com/PolymerElements/iron-selector cd iron-selector npm install npm install -g polymer-cli ``` ### Running the demo locally ```sh polymer serve --npm open http://127.0.0.1:/demo/ ``` ### Running the tests ```sh polymer test --npm ```