From e955cc437852f77b6aab70e49cd4e7118d5578f6 Mon Sep 17 00:00:00 2001
From: Bram Kragten <mail@bramkragten.nl>
Date: Wed, 9 Sep 2020 22:57:44 +0200
Subject: [PATCH] Check for hass when setting themes (#6897)

---
 src/state/themes-mixin.ts | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/src/state/themes-mixin.ts b/src/state/themes-mixin.ts
index 0815f4391a..847f1102f5 100644
--- a/src/state/themes-mixin.ts
+++ b/src/state/themes-mixin.ts
@@ -45,25 +45,28 @@ export default <T extends Constructor<HassBaseEl>>(superClass: T) =>
     }
 
     private _applyTheme(dark: boolean) {
+      if (!this.hass) {
+        return;
+      }
       const themeName =
-        this.hass!.selectedTheme?.theme ||
-        (dark && this.hass!.themes.default_dark_theme
-          ? this.hass!.themes.default_dark_theme!
-          : this.hass!.themes.default_theme);
+        this.hass.selectedTheme?.theme ||
+        (dark && this.hass.themes.default_dark_theme
+          ? this.hass.themes.default_dark_theme!
+          : this.hass.themes.default_theme);
 
       let options: Partial<HomeAssistant["selectedTheme"]> = this.hass!
         .selectedTheme;
 
       if (themeName === "default" && options?.dark === undefined) {
         options = {
-          ...this.hass!.selectedTheme!,
+          ...this.hass.selectedTheme!,
           dark,
         };
       }
 
       applyThemesOnElement(
         document.documentElement,
-        this.hass!.themes,
+        this.hass.themes,
         themeName,
         options
       );
@@ -71,11 +74,11 @@ export default <T extends Constructor<HassBaseEl>>(superClass: T) =>
       const darkMode =
         themeName === "default"
           ? !!options?.dark
-          : !!(dark && this.hass!.themes.default_dark_theme);
+          : !!(dark && this.hass.themes.default_dark_theme);
 
-      if (darkMode !== this.hass!.themes.darkMode) {
+      if (darkMode !== this.hass.themes.darkMode) {
         this._updateHass({
-          themes: { ...this.hass!.themes, darkMode },
+          themes: { ...this.hass.themes, darkMode },
         });
 
         const schemeMeta = document.querySelector("meta[name=color-scheme]");