feat: Improve dark mode support and splash screen handling across app

- Add dark mode background to splash and global styles
- Replace LoadingScreen with SplashScreenComponent for unified splash handling
- Ensure navigation and paper themes sync with dark mode
- Set initial theme based on system preference
- Apply background color to navigation containers and scenes

app.json

@@ -34,7 +34,10 @@
           "image": "./assets/images/racoon-splash.png",
           "imageWidth": 200,
           "resizeMode": "contain",
-          "backgroundColor": "#ffffff"
+          "backgroundColor": "#ffffff",
+          "dark": {
+            "backgroundColor": "#121212"
+          }
         }
       ],
       "expo-secure-store",

app/(tabs)/_layout.tsx

@@ -41,6 +41,9 @@ export default function TabLayout() {
                             </Link>
                         ),
                         tabBarActiveTintColor: theme.colors.primary,
+                        sceneContainerStyle: {
+                            backgroundColor: theme.colors.background,
+                        },
                         tabBarInactiveTintColor: theme.colors.onSurfaceVariant,
                         tabBarStyle: {
                             backgroundColor: theme.colors.surface,

global.css

@@ -3,3 +3,12 @@
 @tailwind utilities;
 
 
+body {
+    background-color: #ffffff;
+}
+
+@media (prefers-color-scheme: dark) {
+    body {
+        background-color: #121212 !important;
+    }
+}

src/components/AuthenticatedWrapper.tsx

@@ -2,28 +2,21 @@ import React, { useEffect } from "react";
 import {useAuth} from "@/src/stores/authStore";
 import {useThemeStore} from "@/src/stores/themeStore";
 import NotAuthenticated from "@/src/components/NotAuthenticated";
-import LoadingScreen from "@/src/components/LoadingScreen";
 import * as SplashScreen from 'expo-splash-screen';
+import SplashScreenComponent from "@/src/components/SplashScreenComponent";
 
 const AuthenticatedWrapper: React.FC<{ children: React.ReactNode }> = ({children}) => {
     const {isAuthenticated, loading, authenticatedUser, isHydrated: authHydrated} = useAuth();
     const {isHydrated: themeHydrated} = useThemeStore();
 
-    // Verstecke den Splash Screen erst wenn beide Stores hydratiert sind
     useEffect(() => {
         if (authHydrated && themeHydrated) {
             SplashScreen.hideAsync().catch(() => {});
         }
     }, [authHydrated, themeHydrated]);
 
-    // Zeige nichts (Splash Screen bleibt) bis beide Stores hydratiert sind
-    if (!authHydrated || !themeHydrated) {
-        return null;
-    }
-
-    // Zeige LoadingScreen während Auth Status geprüft wird
-    if (loading) {
-        return <LoadingScreen />;
+    if (!authHydrated || !themeHydrated || loading) {
+        return <SplashScreenComponent/>;
     }
 
     if (!isAuthenticated || !authenticatedUser) {

src/components/LoadingScreen.tsx

@@ -1,25 +0,0 @@
-import React from "react";
-import { View, ActivityIndicator } from "react-native";
-import Logo from "./Logo";
-import { useThemeStore } from "@/src/stores/themeStore";
-
-export default function LoadingScreen() {
-    const isDark = useThemeStore((state) => state.isDark);
-
-    return (
-        <View
-            className="flex-1 items-center justify-center"
-            style={{
-                backgroundColor: isDark ? '#121212' : '#ffffff'
-            }}
-        >
-            <Logo size="large" />
-            <ActivityIndicator
-                size="large"
-                color={isDark ? '#BB86FC' : '#6200EE'}
-                style={{ marginTop: 20 }}
-            />
-        </View>
-    );
-}
-

src/components/SplashScreenComponent.tsx

@@ -0,0 +1,27 @@
+import React from 'react';
+import { View, Image, useColorScheme } from 'react-native';
+import { useThemeStore } from '@/src/stores/themeStore';
+
+export default function SplashScreenComponent() {
+    const systemColorScheme = useColorScheme();
+
+    const { isDark, isHydrated } = useThemeStore();
+
+    const effectiveIsDark = isHydrated ? isDark : systemColorScheme === 'dark';
+
+    return (
+        <View
+            style={{
+                flex: 1,
+                backgroundColor: effectiveIsDark ? '#121212' : '#ffffff',
+                alignItems: 'center',
+                justifyContent: 'center'
+            }}
+        >
+            <Image
+                source={require('@/assets/images/racoon-splash.png')}
+                style={{ width: 200, resizeMode: 'contain' }}
+            />
+        </View>
+    );
+}

src/context/ThemeProvider.tsx

@@ -1,26 +1,40 @@
 import React, {ReactNode, useEffect} from "react";
-import {Provider as PaperProvider} from "react-native-paper";
+import {adaptNavigationTheme, Provider as PaperProvider} from "react-native-paper";
 import {useThemeStore} from "@/src/stores/themeStore";
 import {useColorScheme} from "nativewind";
-import LoadingScreen from "@/src/components/LoadingScreen";
-import * as SplashScreen from 'expo-splash-screen';
+import SplashScreenComponent from "@/src/components/SplashScreenComponent";
+
+import { ThemeProvider as NavThemeProvider, DarkTheme, DefaultTheme } from '@react-navigation/native';
+import {View} from "react-native";
 
-SplashScreen.preventAutoHideAsync().catch(() => {});
 
 export const ThemeProvider = ({children}: { children: ReactNode }) => {
     const { theme, isDark, isHydrated } = useThemeStore();
     const { setColorScheme } = useColorScheme();
 
+    const { LightTheme: NavLightTheme, DarkTheme: NavDarkTheme } = adaptNavigationTheme({
+        reactNavigationLight: DefaultTheme,
+        reactNavigationDark: DarkTheme,
+    });
+
+    const navigationTheme = isDark ? NavDarkTheme : NavLightTheme;
+
     useEffect(() => {
         setColorScheme(isDark ? 'dark' : 'light');
-    }, [isDark, setColorScheme]);
+    }, [isDark, setColorScheme, isHydrated]);
 
     if (!isHydrated) {
-        return <LoadingScreen />;
+        return <SplashScreenComponent />;
     }
 
     return (
-        <PaperProvider theme={theme}>{children}</PaperProvider>
+        <NavThemeProvider value={navigationTheme}>
+            <PaperProvider theme={theme}>
+                <View style={{ flex: 1, backgroundColor: theme.colors.background }}>
+                    {children}
+                </View>
+            </PaperProvider>
+        </NavThemeProvider>
     );
 };
 

src/core/Stack.tsx

@@ -1,10 +1,12 @@
 import React from "react";
 import {Slot, Stack} from "expo-router";
+import {useThemeStore} from "@/src/stores";
 
 
 export default function CustomStack() {
+    const { theme } = useThemeStore();
     return (
-        <Stack screenOptions={{ headerShown: false }}>
+        <Stack screenOptions={{ headerShown: false, contentStyle: { backgroundColor: theme.colors.background } }}>
             <Slot />
         </Stack>
     );

src/stores/themeStore.ts

@@ -1,8 +1,15 @@
-import { create } from 'zustand';
-import { persist, createJSONStorage } from 'zustand/middleware';
-import { Platform } from 'react-native';
+import {create} from 'zustand';
+import {persist, createJSONStorage} from 'zustand/middleware';
+import {Platform} from 'react-native';
 import * as SecureStore from 'expo-secure-store';
-import { CustomMD3Theme, darkTheme, lightTheme } from '@/src/core/theme';
+import {CustomMD3Theme, darkTheme, lightTheme} from '@/src/core/theme';
+
+const getSystemThemeIsDark = () => {
+    if (Platform.OS === 'web' && typeof window !== 'undefined') {
+        return window.matchMedia('(prefers-color-scheme: dark)').matches;
+    }
+    return false;
+};
 
 const zustandStorage = {
     getItem: async (name: string): Promise<string | null> => {
@@ -37,23 +44,27 @@ interface ThemeState {
 
 export const useThemeStore = create<ThemeState>()(
     persist(
-        (set, get) => ({
-            theme: lightTheme,
-            isDark: false,
-            isHydrated: false,
-            toggleTheme: () => {
-                const newIsDark = !get().isDark;
-                set({
-                    isDark: newIsDark,
-                    theme: newIsDark ? darkTheme : lightTheme,
-                });
-            },
-            setHydrated: () => set({ isHydrated: true }),
-        }),
+        (set, get) => {
+            const initialDark = getSystemThemeIsDark();
+
+            return {
+                theme: initialDark ? darkTheme : lightTheme,
+                isDark: initialDark,
+                isHydrated: false,
+                toggleTheme: () => {
+                    const newIsDark = !get().isDark;
+                    set({
+                        isDark: newIsDark,
+                        theme: newIsDark ? darkTheme : lightTheme,
+                    });
+                },
+                setHydrated: () => set({isHydrated: true}),
+            };
+        },
         {
             name: 'theme-storage',
             storage: createJSONStorage(() => zustandStorage),
-            partialize: (state) => ({ isDark: state.isDark }),
+            partialize: (state) => ({isDark: state.isDark}),
             onRehydrateStorage: () => (state) => {
                 if (state) {
                     state.theme = state.isDark ? darkTheme : lightTheme;