Theme Switcher Code

Theme Preview

Framework

/* Theme Variables */

/* LIGHT Theme */
:root[data-theme="light"],
.theme-light {
  --bg-primary: #ffffff;
  --text-primary: #111827;
  --border-color: #e5e7eb;
}

/* DARK Theme */
:root[data-theme="dark"],
.theme-dark {
  --bg-primary: #111827;
  --text-primary: #f9fafb;
  --border-color: #374151;
}

/* System Dark Mode Preference */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --bg-primary: #111827;
    --text-primary: #f9fafb;
    --border-color: #374151;
  }
}

import { createContext, useContext, useEffect, useState, ReactNode } from 'react';

type Theme = 'light' | 'dark';

interface ThemeContextType {
  theme: Theme;
  setTheme: (theme: Theme) => void;
  themes: Theme[];
}

const ThemeContext = createContext<ThemeContextType | undefined>(undefined);

export function ThemeProvider({ children }: { children: ReactNode }) {
  const [theme, setThemeState] = useState<Theme>('light');
  const [mounted, setMounted] = useState(false);

  useEffect(() => {
    setMounted(true);
    // Get theme from localStorage or system preference
    const stored = localStorage.getItem('theme') as Theme;

    if (stored) {
      setThemeState(stored);
    } else if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
      setThemeState('dark');
    }
  }, []);

  useEffect(() => {
    if (!mounted) return;

    const root = document.documentElement;

    // Remove all theme classes
    root.classList.remove('theme-light');
    root.classList.remove('theme-dark');

    // Add current theme class
    root.classList.add(`theme-${theme}`);

    // Set data attribute
    root.setAttribute('data-theme', theme);

    // Store in localStorage
    localStorage.setItem('theme', theme);
  }, [theme, mounted]);

  const setTheme = (newTheme: Theme) => {
    setThemeState(newTheme);
  };

  if (!mounted) {
    return null;
  }

  return (
    <ThemeContext.Provider value={{ theme, setTheme, themes: ['light', 'dark'] }}>
      {children}
    </ThemeContext.Provider>
  );
}

export function useTheme() {
  const context = useContext(ThemeContext);
  if (context === undefined) {
    throw new Error('useTheme must be used within a ThemeProvider');
  }
  return context;
}

// Theme Switcher Component
export function ThemeSwitcher() {
  const { theme, setTheme, themes } = useTheme();

  return (
    <div className="theme-switcher">
      <label htmlFor="theme-select">Theme:</label>
      <select
        id="theme-select"
        value={theme}
        onChange={(e) => setTheme(e.target.value as Theme)}
      >
        {themes.map((t) => (
          <option key={t} value={t}>
            {t.charAt(0).toUpperCase() + t.slice(1)}
          </option>
        ))}
      </select>
    </div>
  );
}

// Theme Toggle Button (for light/dark)
export function ThemeToggle() {
  const { theme, setTheme } = useTheme();

  const toggleTheme = () => {
    setTheme(theme === 'light' ? 'dark' : 'light');
  };

  return (
    <button
      onClick={toggleTheme}
      className="theme-toggle"
      aria-label="Toggle theme"
    >
      {theme === 'light' ? '🌙' : '☀️'}
    </button>
  );
}