Creates a basic button.
By default, the button renders the contents of its direct children (i.e. it has a single unnamed <slot>).
Subclasses can override this by overriding render.
Optionaloptions: ButtonOptionsWhether the button is disabled.
When disabled, the button cannot be clicked.
The lang property of the HTMLElement interface indicates the base language of an element's attribute values and text content, in the form of a BCP 47 language tag. It reflects the element's lang attribute; the xml:lang attribute does not affect this property.
The ID of the menu to open.
Protected Readonly_Protected Readonly_ProtectedhandleHandle a button click.
By default, this does nothing. Subclasses can override this method to add behavior to the button.
Invoked when the component is added to the document's DOM.
In connectedCallback() you should setup tasks that should only occur when
the element is connected to the document. The most common of these is
adding event listeners to nodes external to the element, like a keydown
event handler added to the window.
connectedCallback() {
super.connectedCallback();
addEventListener('keydown', this._handleKeydown);
}
Typically, anything done in connectedCallback() should be undone when the
element is disconnected, in disconnectedCallback().
Invoked when the component is removed from the document's DOM.
This callback is the main signal to the element that it may no longer be
used. disconnectedCallback() should ensure that nothing is holding a
reference to the element (such as event listeners added to nodes external
to the element), so that it is free to be garbage collected.
disconnectedCallback() {
super.disconnectedCallback();
window.removeEventListener('keydown', this._handleKeydown);
}
An element may be re-connected after being disconnected.
ProtectedrenderInvoked on each update to perform rendering tasks. This method may return
any value renderable by lit-html's ChildPart - typically a
TemplateResult. Setting properties inside this method will not trigger
the element to update.
StaticstylesArray of styles to apply to the element. The styles should be defined
using the css tag function, via constructible stylesheets, or
imported from native CSS module scripts.
Note on Content Security Policy:
Element styles are implemented with <style> tags when the browser doesn't
support adopted StyleSheets. To use such <style> tags with the style-src
CSP directive, the style-src value must either include 'unsafe-inline' or
nonce-<base64-value> with <base64-value> replaced be a server-generated
nonce.
To provide a nonce to use on generated <style> elements, set
window.litNonce to a server-generated nonce in your page's HTML, before
loading application code:
<script>
// Generated and unique per request:
window.litNonce = 'a1b2c3d4';
</script>
Invoked before update() to compute values needed during the update.
Implement willUpdate to compute property values that depend on other
properties and are used in the rest of the update process.
willUpdate(changedProperties) {
// only need to check changed properties for an expensive computation.
if (changedProperties.has('firstName') || changedProperties.has('lastName')) {
this.sha = computeSHA(`${this.firstName} ${this.lastName}`);
}
}
render() {
return html`SHA: ${this.sha}`;
}
A menu button that opens a [playback rate menu]PlaybackRateMenu.
Custom Element
<theoplayer-playback-rate-menu-button>Attributes
menu
The ID of the playback rate menu.
langThe
langproperty of the HTMLElement interface indicates the base language of an element's attribute values and text content, in the form of a BCP 47 language tag. It reflects the element's lang attribute; the xml:lang attribute does not affect this property.MDN Reference
menuThe ID of the menu to open.
disabledWhether the button is disabled.
When disabled, the button cannot be clicked.
aria-labelMDN Reference