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.
OptionalnameOptionaliconOptionalpreferredOptionalsignersOptionalclientSets the active client and transfers its ownership to the connector. The connector may close the client when it is replaced or disconnected.
OptionalwalletOptionalsignerOptionalonClosed: () => voidInvoked 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}`;
}
Invoked whenever the element is updated. Implement to perform post-updating tasks via DOM APIs, for example, focusing an element.
Setting properties inside this method will trigger the element to update again after this update cycle completes.
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.Typically, anything done in
connectedCallback()should be undone when the element is disconnected, indisconnectedCallback().