Title bar

With Config::titleBar = true, your content runs to the top edge of the window and you draw the title bar yourself with ImGui, like any other UI. mydear does the platform part:

• the OS’s own window buttons stay where users expect them (on macOS, the traffic lights);
• empty bar space drags the window;
• a double-click on empty bar space does what the OS setting says (zoom, minimize, or nothing).

auto bar = mydear::BeginTitleBar();
if (mydear::IconButton(ICON_SIDEBAR))
    toggleSidebar();
ImGui::SetCursorScreenPos({bar.pos.x + bar.size.x - bar.rightInset - 80, ImGui::GetCursorScreenPos().y});
if (mydear::IconButton(ICON_GEAR))
    openSettings();
mydear::EndTitleBar();

Lay the rest of the UI out below mydear::TitleBarHeight().

What BeginTitleBar returns

The cursor starts at leftInset, vertically centred for a row of frame-height widgets.

Laying out below it

mydear::ContentRect() (mydear/app.hpp) is the rest of the window: below the bar and inside SafeArea(). Give it to the app’s main window. On iOS there is no strip: TitleBarHeight() is 0 and BeginTitleBar()/EndTitleBar() draw nothing, so the same code builds there.

Height

Config::titleBarHeight sets the bar’s height in points; 0, the default, takes the platform’s own: 28 on macOS, 32 on Windows, 36 on Linux, 44 on Android. On macOS 28 matches the system’s own title bar. A taller bar moves the traffic lights down so they stay centred. AppKit puts them back on every resize and when leaving fullscreen, so mydear re-checks each frame and only moves them when something changed.

How clicks are decided

Whether a click hits a widget is only known after ImGui has processed it, so mydear decides at the end of the frame, in EndTitleBar:

• if no ImGui item took the click and the mouse is still down, the window drag starts after the frame is presented;
• a double-click runs the OS setting’s action instead;
• a click on the bar hands keyboard focus back to the window that had it, so typing continues where it was.

Widgets in the bar, ImGui items or native views, never start a drag.

Fullscreen

In fullscreen the OS shows its own title bar when the mouse reaches the top edge, over yours. The insets are 0 there, since the traffic lights are not in the window.

Dark mode

mydear gives the window Theme::Current()’s appearance (Dark Aqua or Aqua) and its base colour as the window background whenever the theme changes, so the traffic lights, sheets, native views and the edge of a live resize match.

Windows

There is no system frame: mydear removes it (WM_NCCALCSIZE), keeps the window shadow with DwmExtendFrameIntoClientArea, and draws the minimize, maximize and close buttons itself at the right end of the bar (rightInset is their width, 138 pixels). They follow the theme, and close turns red on hover, like Windows’ own.

• Snap layouts: the maximize button answers HTMAXBUTTON to Windows’ hit test, so hovering it on Windows 11 opens the snap layout flyout, and Windows itself handles the click.
• Dragging: empty bar space starts the system move loop, so Aero Snap (drag to an edge), shake and moving between screens work.
• Double-click toggles maximize; right-click opens the window menu (Restore, Move, Size, Minimize, Maximize, Close).
• Resize: the window edges still resize, by the system frame width.
• Dark mode: mydear sets DWMWA_USE_IMMERSIVE_DARK_MODE from Theme::Current()->dark every time the theme changes, so borders and snap previews match.
• Maximized, the window stays inside the work area instead of covering the taskbar.

Config::titleBarHeight is in pixels on Windows; 32 matches the system caption.

Linux

The window gets an empty client-side titlebar, so GTK still draws the window shadow and resize edges, and the bar is yours. mydear draws the window buttons in the order gtk-decoration-layout gives (GNOME: close on the right; elementary and others: on the left), so leftInset and rightInset follow it.

• Dragging: empty bar space calls gdk_toplevel_begin_move, so the compositor moves the window (Wayland and X11).
• Double-click toggles maximize; right-click opens the window manager’s menu (gdk_toplevel_show_window_menu).
• Dark mode: mydear sets gtk-application-prefer-dark-theme from Theme::Current()->dark, so GTK dialogs and native views match.

Config::titleBarHeight is in logical pixels on Linux.