Menubar

Overview

class omdi::Menubar

Top menubar component for omdi applications.

The omdi::Menubar class manages a main menu bar at the top of the application window using ImGui. It supports three alignment zones:

• left: typically for application menus (File, Edit, View, …),

• center: for status or mode selectors,

• right: for utility items (profile, settings, help, etc.).

Each menu item is represented as a omdi::MenuItem holding a render callback (std::function<void()>). Rendering is performed inside omdi::Menubar::render(), which also integrates with omdi::safe::Render() to catch exceptions and optionally show error toasts via omdi::ToastManager.

For example usage, see the getting started guide.

Related types

struct omdi::MenuItem

Small helper struct storing a single menu item render callback.

std::function<void()> omdi::MenuItem::render

Callable used to render the menu item (e.g. ImGui menu entries).

Public interface

void omdi::Menubar::AddLeft(const std::function<void()> &item)

Add a menu item to the left-aligned section of the menubar.

Parameters:

item – Render callback for the item. Typically this lambda will contain ImGui menu code, such as calls to ImGui::BeginMenu() / ImGui::MenuItem() or a wrapper like SafeMenu.

Items are rendered in the order they are added.

void omdi::Menubar::AddCenter(const std::function<void()> &item)

Add a menu item to the center-aligned section of the menubar.

Parameters:

item – Render callback for the item.

The menubar computes the total width of center items and places them so they appear centered within the available menu bar width.

void omdi::Menubar::AddRight(const std::function<void()> &item)

Add a menu item to the right-aligned section of the menubar.

Parameters:

item – Render callback for the item.

Right-aligned items are rendered flush against the right edge of the menubar, taking into account their total width.

void omdi::Menubar::render(omdi::ToastManager *toastManager = nullptr) const

Render the menubar and all registered items.

Parameters:

toastManager – Optional pointer to omdi::ToastManager. When provided, each item is executed via omdi::safe::Render(), so exceptions thrown inside item callbacks are logged and can trigger error toasts.

Behavior:

• Begins the main menu bar with ImGui::BeginMainMenuBar().

• Renders left-aligned items in sequence, separated by SameLine.

• Measures the widths of center and right sections using an off-screen dummy window (via a private measureWidth() helper).

• Positions and renders right-aligned items at the right edge.

• Positions and renders center-aligned items so they are visually centered.

• Ends the menu bar with ImGui::EndMainMenuBar().

All per-item render callbacks are invoked within an ImGui context and may use functions like ImGui::BeginMenu(), ImGui::MenuItem(), or custom wrappers such as SafeMenu.

Notes

• omdi::Menubar does not own the ImGui context; it assumes ImGui has been initialized and a frame is in progress.

• For robust error handling, it is recommended to pass a valid omdi::ToastManager pointer to omdi::Menubar::render(), so exceptions thrown by menu item callbacks result in logged errors and visual feedback to the user.

• Width measurement uses a hidden dummy window positioned off-screen to let ImGui compute the layout of center and right sections without affecting the visible UI.