state.hpp

浏览该文件的文档.

#ifndef NEFORCE_TUI_DOM_STATE_HPP__
#define NEFORCE_TUI_DOM_STATE_HPP__

 
#include "NeForce/core/async/signals.hpp"
#include "NeForce/core/async/strand.hpp"
NEFORCE_BEGIN_NAMESPACE__
NEFORCE_BEGIN_TUI__


class component_base;
 

template <typename T>
class state {
public:
    using changed_signal = signal<T>;

    state(component_base* owner, strand& s, T initial) :
    value_(_NEFORCE move(initial)),
    strand_(&s),
    owner_(owner) {}
 
    ~state() = default;
 
    state(const state&) = delete;
    state& operator=(const state&) = delete;
    state(state&&) = delete;
    state& operator=(state&&) = delete;

    NEFORCE_NODISCARD const T& value() const noexcept { return value_; }

    NEFORCE_NODISCARD const T& operator*() const noexcept { return value_; }

    NEFORCE_NODISCARD const T* operator->() const noexcept { return &value_; }

    state& operator=(T v) {
        value_ = _NEFORCE move(v);
        notify_changed();
        return *this;
    }

    void modify(function<void(T&)> fn) {
        fn(value_);
        notify_changed();
    }

    void set_quiet(T v) {
        value_ = _NEFORCE move(v);
        on_changed_.emit(value_);
        dirty_ = true;
    }

    void notify() {
        if (dirty_) {
            dirty_ = false;
            schedule_render();
        }
    }

    connection on_change(function<void(const T&)> fn) {
        return on_changed_.connect([fn = _NEFORCE move(fn)](const T& val) { fn(val); });
    }
 
private:
    T value_;
    changed_signal on_changed_;
    strand* strand_;
    component_base* owner_;
    bool dirty_ = false;
 
    void notify_changed() {
        on_changed_.emit(value_);
        schedule_render();
    }
 
    void schedule_render();
};
 // TUI
 
NEFORCE_END_TUI__
NEFORCE_END_NAMESPACE__
#endif // NEFORCE_TUI_DOM_STATE_HPP__