fune/toolkit/content/widgets/lit-utils.mjs

100 lines
2.7 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
// Bug 1790483: Lit is not bundled yet, this is dev only.
// eslint-disable-next-line import/no-unresolved
import { query, queryAll, LitElement } from "./vendor/lit.all.mjs";
/**
* MozLitElement provides extensions to the lit-provided LitElement class.
*
*******
*
* `@query` support (define a getter for a querySelector):
*
* static get queries() {
* return {
* propertyName: ".aNormal .cssSelector",
* anotherName: { all: ".selectorFor .querySelectorAll" },
* };
* }
*
* This example would add properties that would be written like this without
* using `queries`:
*
* get propertyName() {
* return this.renderRoot?.querySelector(".aNormal .cssSelector");
* }
*
* get anotherName() {
* return this.renderRoot?.querySelectorAll(".selectorFor .querySelectorAll");
* }
*******
*
* Automatic Fluent support for shadow DOM.
*
* Fluent requires that a shadowRoot be connected before it can use Fluent.
* Shadow roots will get connected automatically.
*
*******
*
* Test helper for sending events after a change: `dispatchOnUpdateComplete`
*
* When some async stuff is going on and you want to wait for it in a test, you
* can use `this.dispatchOnUpdateComplete(myEvent)` and have the test wait on
* your event.
*
* The component will then wait for your reactive property change to take effect
* and dispatch the desired event.
*
* Example:
*
* async onClick() {
* let response = await this.getServerResponse(this.data);
* // Show the response status to the user.
* this.responseStatus = respose.status;
* this.dispatchOnUpdateComplete(
* new CustomEvent("status-shown")
* );
* }
*
* add_task(async testButton() {
* let button = this.setupAndGetButton();
* button.click();
* await BrowserTestUtils.waitForEvent(button, "status-shown");
* });
*/
export class MozLitElement extends LitElement {
constructor() {
super();
let { queries } = this.constructor;
if (queries) {
for (let [name, selector] of Object.entries(queries)) {
if (selector.all) {
queryAll(selector.all)(this, name);
} else {
query(selector)(this, name);
}
}
}
}
connectedCallback() {
super.connectedCallback();
if (!this._l10nRootConnected && document.l10n) {
document.l10n.connectRoot(this.renderRoot);
this._l10nRootConnected = true;
}
}
async dispatchOnUpdateComplete(event) {
await this.updateComplete;
this.dispatchEvent(event);
}
update() {
super.update();
document.l10n.translateFragment(this.renderRoot);
}
}