Move panel readiness setup to constructor

src/layouts/panel-ready.ts

@@ -1,3 +1,5 @@
+import { ContextProvider, createContext } from "@lit/context";
+import type { ReactiveController, ReactiveControllerHost } from "lit";
 import { ReactiveElement } from "lit";
 import { fireEvent } from "../common/dom/fire_event";
 
@@ -15,6 +17,43 @@ export const panelIsReady = async (element: HTMLElement) => {
   fireEvent(element, "hass-panel-ready");
 };
 
+export type RegisterChildPanelReady = (ready: Promise<void>) => void;
+
+export const childPanelReadyContext =
+  createContext<RegisterChildPanelReady>("child-panel-ready");
+
+export class ChildPanelReady implements ReactiveController {
+  private _promises: Promise<void>[] = [];
+
+  private _host: ReactiveControllerHost & HTMLElement;
+
+  private _resolveReady?: () => void;
+
+  public ready = new Promise<void>((resolve) => {
+    this._resolveReady = resolve;
+  });
+
+  public constructor(host: ReactiveControllerHost & HTMLElement) {
+    this._host = host;
+    host.addController(this);
+    new ContextProvider(host, {
+      context: childPanelReadyContext,
+      initialValue: (ready) => this._promises.push(ready),
+    });
+  }
+
+  public hostUpdated() {
+    Promise.all(this._promises).then(
+      () => {
+        this._resolveReady?.();
+        return panelIsReady(this._host);
+      },
+      () => undefined
+    );
+    this._host.removeController(this);
+  }
+}
+
 export class PanelReady {
   public ready?: Promise<void>;
 

src/panels/config/dashboard/ha-config-dashboard.ts

@@ -36,6 +36,7 @@ import { showQuickBar } from "../../../dialogs/quick-bar/show-dialog-quick-bar";
 import { showRestartDialog } from "../../../dialogs/restart/show-dialog-restart";
 import { showShortcutsDialog } from "../../../dialogs/shortcuts/show-shortcuts-dialog";
 import type { PageNavigation } from "../../../layouts/hass-tabs-subpage";
+import { ChildPanelReady } from "../../../layouts/panel-ready";
 import { SubscribeMixin } from "../../../mixins/subscribe-mixin";
 import { haStyle } from "../../../resources/styles";
 import type { HomeAssistant } from "../../../types";
@@ -157,6 +158,11 @@ class HaConfigDashboard extends SubscribeMixin(LitElement) {
     total: 0,
   };
 
+  public constructor() {
+    super();
+    new ChildPanelReady(this);
+  }
+
   private _pages = memoizeOne(
     (
       cloudStatus,

src/panels/config/dashboard/ha-config-navigation.ts

@@ -1,4 +1,5 @@
-import type { CSSResultGroup, PropertyValues, TemplateResult } from "lit";
+import { consume } from "@lit/context";
+import type { CSSResultGroup, TemplateResult } from "lit";
 import { css, html, LitElement } from "lit";
 import { customElement, property, state } from "lit/decorators";
 import { filterNavigationPages } from "../../../common/config/filter_navigation_pages";
@@ -7,6 +8,10 @@ import "../../../components/ha-icon-next";
 import type { CloudStatus } from "../../../data/cloud";
 import { getConfigEntries } from "../../../data/config_entries";
 import type { PageNavigation } from "../../../layouts/hass-tabs-subpage";
+import {
+  childPanelReadyContext,
+  type RegisterChildPanelReady,
+} from "../../../layouts/panel-ready";
 import type { HomeAssistant } from "../../../types";
 import "../components/ha-config-navigation-list";
 
@@ -18,21 +23,20 @@ class HaConfigNavigation extends LitElement {
 
   @property({ attribute: false }) public pages!: PageNavigation[];
 
-  @state() private _hasBluetoothConfigEntries = false;
+  @state() private _visiblePages?: PageNavigation[];
 
-  protected firstUpdated(changedProps: PropertyValues<this>) {
-    super.firstUpdated(changedProps);
-    getConfigEntries(this.hass, {
-      domain: "bluetooth",
-    }).then((bluetoothEntries) => {
-      this._hasBluetoothConfigEntries = bluetoothEntries.length > 0;
-    });
+  private _hasBluetoothConfigEntries = false;
+
+  @consume({ context: childPanelReadyContext })
+  private _registerChildPanelReady?: RegisterChildPanelReady;
+
+  public connectedCallback() {
+    super.connectedCallback();
+    this._registerChildPanelReady?.(this._resolveVisiblePages());
   }
 
   protected render(): TemplateResult {
-    const pages = filterNavigationPages(this.hass, this.pages, {
-      hasBluetoothConfigEntries: this._hasBluetoothConfigEntries,
-    }).map((page) => ({
+    const pages = (this._visiblePages ?? []).map((page) => ({
       ...page,
       name:
         page.name ||
@@ -75,6 +79,20 @@ class HaConfigNavigation extends LitElement {
     `;
   }
 
+  private async _resolveVisiblePages(): Promise<void> {
+    if (this.pages.some((page) => page.component === "bluetooth")) {
+      const entries = await getConfigEntries(this.hass, {
+        domain: "bluetooth",
+      });
+      this._hasBluetoothConfigEntries = entries.length > 0;
+    }
+
+    this._visiblePages = filterNavigationPages(this.hass, this.pages, {
+      hasBluetoothConfigEntries: this._hasBluetoothConfigEntries,
+    });
+    await this.updateComplete;
+  }
+
   static styles: CSSResultGroup = css`
     /* Accessibility */
     .visually-hidden {

src/panels/config/ha-panel-config.ts

@@ -89,6 +89,7 @@ class HaPanelConfig extends HassRouterPage {
       dashboard: {
         tag: "ha-config-dashboard",
         load: () => import("./dashboard/ha-config-dashboard"),
+        waitForReady: true,
       },
       entities: {
         tag: "ha-config-entities",