HeaderBar

class HeaderBar(**properties: Any)

Superclasses: Widget, InitiallyUnowned, Object

Implemented Interfaces: Accessible, Buildable, ConstraintTarget

GtkHeaderBar is a widget for creating custom title bars for windows.

GtkHeaderBar is similar to a horizontal GtkCenterBox. It allows children to be placed at the start or the end. In addition, it allows the window title to be displayed. The title will be centered with respect to the width of the box, even if the children at either side take up different amounts of space.

GtkHeaderBar can add typical window frame controls, such as minimize, maximize and close buttons, or the window icon.

For these reasons, GtkHeaderBar is the natural choice for use as the custom titlebar widget of a GtkWindow (see set_titlebar), as it gives features typical of titlebars while allowing the addition of child widgets.

GtkHeaderBar as GtkBuildable

The GtkHeaderBar implementation of the GtkBuildable interface supports adding children at the start or end sides by specifying “start” or “end” as the “type” attribute of a <child> element, or setting the title widget by specifying “title” value.

By default the GtkHeaderBar uses a GtkLabel displaying the title of the window it is contained in as the title widget, equivalent to the following UI definition:

<object class="GtkHeaderBar">
  <property name="title-widget">
    <object class="GtkLabel">
      <property name="label" translatable="yes">Label</property>
      <property name="single-line-mode">True</property>
      <property name="ellipsize">end</property>
      <property name="width-chars">5</property>
      <style>
        <class name="title"/>
      </style>
    </object>
  </property>
</object>

CSS nodes

headerbar
╰── windowhandle
    ╰── box
        ├── box.start
        │   ├── windowcontrols.start
        │   ╰── [other children]
        ├── [Title Widget]
        ╰── box.end
            ├── [other children]
            ╰── windowcontrols.end

A GtkHeaderBar’s CSS node is called headerbar. It contains a windowhandle subnode, which contains a box subnode, which contains two box subnodes at the start and end of the header bar, as well as a center node that represents the title.

Each of the boxes contains a windowcontrols subnode, see WindowControls for details, as well as other children.

Accessibility

GtkHeaderBar uses the GROUP role.

Constructors

class HeaderBar

classmethod new() → Widget: Creates a new GtkHeaderBar widget.

Methods

class HeaderBar

get_decoration_layout() → str | None: Gets the decoration layout of the GtkHeaderBar.

get_show_title_buttons() → bool: Returns whether this header bar shows the standard window title buttons.

get_title_widget() → Widget | None

Retrieves the title widget of the header.

See set_title_widget.

pack_end(child: Widget) → None

Adds child to bar, packed with reference to the end of the bar.

Parameters:: child – the GtkWidget to be added to bar

pack_start(child: Widget) → None

Adds child to bar, packed with reference to the start of the bar.

Parameters:: child – the GtkWidget to be added to bar

remove(child: Widget) → None

Removes a child from the GtkHeaderBar.

The child must have been added with pack_start, pack_end or set_title_widget.

Parameters:: child – the child to remove

set_decoration_layout(layout: str | None = None) → None

Sets the decoration layout for this header bar.

This property overrides the gtk_decoration_layout setting.

There can be valid reasons for overriding the setting, such as a header bar design that does not allow for buttons to take room on the right, or only offers room for a single close button. Split header bars are another example for overriding the setting.

The format of the string is button names, separated by commas. A colon separates the buttons that should appear on the left from those on the right. Recognized button names are minimize, maximize, close and icon (the window icon).

For example, “icon:minimize,maximize,close” specifies an icon on the left, and minimize, maximize and close buttons on the right.

Parameters:: layout – a decoration layout, or None to unset the layout

set_show_title_buttons(setting: bool) → None

Sets whether this header bar shows the standard window title buttons.

Parameters:: setting – True to show standard title buttons

set_title_widget(title_widget: Widget | None = None) → None

Sets the title for the GtkHeaderBar.

When set to None, the headerbar will display the title of the window it is contained in.

The title should help a user identify the current view. To achieve the same style as the builtin title, use the “title” style class.

You should set the title widget to None, for the window title label to be visible again.

Parameters:: title_widget – a widget to use for a title

Properties

class HeaderBar

props.decoration_layout: str

The decoration layout for buttons.

If this property is not set, the gtk_decoration_layout setting is used.

props.show_title_buttons: bool

Whether to show title buttons like close, minimize, maximize.

Which buttons are actually shown and where is determined by the decoration_layout property, and by the state of the window (e.g. a close button will not be shown if the window can’t be closed).

props.title_widget: Widget