ThemeManager.h

Go to the documentation of this file.

//
// ThemeManager.h
//
 
#ifndef MALENA_THEMEMANAGER_H
#define MALENA_THEMEMANAGER_H
 
#pragma once
 
#include <Malena/Core/malena_export.h>
#include <Malena/Manifests/Theme.h>
#include <Malena/Manifests/ThemeTag.h>
#include <Malena/Manifests/Manifest.h>
#include <Malena/Core/DeferredOperationsManager.h>
#include <vector>
#include <memory>
#include <algorithm>
 
namespace ml
{
    class Themeable;
 
    // ── ThemeManager ─────────────────────────────────────────────────────────

    class MALENA_API ThemeManager : public DeferredOperationsManager<ThemeManager>
    {
    public:
        // ── Reading ───────────────────────────────────────────────────────────

        static const Theme& get();
 
        // ── Applying themes ───────────────────────────────────────────────────

        template<typename MANIFEST>
        static void apply(typename MANIFEST::Themes themeKey)
        {
            const ThemeTag& tag = Manifest::getTheme(themeKey);
            applyTheme(static_cast<const Theme&>(tag));
        }

        template<typename T>
        static void set(const T& theme)
        {
            static_assert(std::is_base_of_v<Theme, T>,
                "ThemeManager::set() requires a type derived from ml::Theme");
            _active = std::make_unique<T>(theme);
            notify();
        }
 
        // ── Subscription (called by Themeable — not for user code) ────────────

        static void subscribe(Themeable* component);

        static void unsubscribe(Themeable* component);
 
        // ── Lifecycle ─────────────────────────────────────────────────────────

        static void shutdown();
 
    private:
        static void applyTheme(const Theme& theme);

        static void notify();
 
        inline static std::unique_ptr<Theme>  _active      = std::make_unique<DarkTheme>();
        inline static std::vector<Themeable*> _subscribers = {};
        inline static bool                    _destroyed   = false;
    };
 
} // namespace ml
 
#endif // MALENA_THEMEMANAGER_H