tab_widget.hpp

// Copyright Take Vos 2020-2021.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
 
#pragma once
 
#include "widget.hpp"
#include "grid_widget.hpp"
#include "tab_delegate.hpp"
#include "default_tab_delegate.hpp"
 
namespace hi::inline v1 {
 
class tab_widget final : public widget {
public:
    using super = widget;
    using delegate_type = tab_delegate;
 
    ~tab_widget();
 
    tab_widget(gui_window &window, widget *parent, std::weak_ptr<delegate_type> delegate) noexcept;
 
    template<typename Value>
    tab_widget(gui_window &window, widget *parent, Value &&value) noexcept
        requires(not std::is_convertible_v<Value, weak_or_unique_ptr<delegate_type>>) :
        tab_widget(window, parent, make_unique_default_tab_delegate(std::forward<Value>(value)))
    {
    }
 
    template<typename WidgetType, typename Key, typename... Args>
    WidgetType &make_widget(Key const &key, Args &&...args)
    {
        hi_axiom(is_gui_thread());
 
        auto tmp = std::make_unique<WidgetType>(window, this, std::forward<Args>(args)...);
        auto &ref = *tmp;
        if (auto delegate = _delegate.lock()) {
            delegate->add_tab(*this, static_cast<std::size_t>(key), size(_children));
        }
        _children.push_back(std::move(tmp));
        request_reconstrain();
        return ref;
    }
 
    [[nodiscard]] generator<widget *> children() const noexcept override
    {
        for (hilet &child : _children) {
            co_yield child.get();
        }
    }
 
    widget_constraints const &set_constraints() noexcept override;
    void set_layout(widget_layout const &layout) noexcept override;
    void draw(draw_context const &context) noexcept override;
    [[nodiscard]] hitbox hitbox_test(point3 position) const noexcept override;
    [[nodiscard]] widget const *find_next_widget(
        widget const *current_widget,
        keyboard_focus_group group,
        keyboard_focus_direction direction) const noexcept override;
private:
    widget const *_previous_selected_child = nullptr;
    std::vector<std::unique_ptr<widget>> _children;
    weak_or_unique_ptr<delegate_type> _delegate;
    notifier<>::token_type _delegate_cbt;
 
    using const_iterator = decltype(_children)::const_iterator;
 
    tab_widget(gui_window &window, widget *parent, weak_or_unique_ptr<delegate_type> delegate) noexcept;
    [[nodiscard]] const_iterator find_selected_child() const noexcept;
    [[nodiscard]] widget &selected_child() const noexcept;
};
 
} // namespace hi::inline v1