Sets our main struct and passes it to the parent class.
Creates a new #GtkOverlay.
The ::get-child-position signal is emitted to determine the position and size of any overlay child widgets. A handler for this signal should fill @allocation with the desired position and size for @widget, relative to the 'main' child of @overlay.
Adds @widget to @overlay.
Convenience function to get the value of the #GtkOverlay:pass-through child property for @widget.
Get the main Gtk struct
the main Gtk struct as a void*
Moves @child to a new @index in the list of @overlay children. The list contains overlays in the order that these were added to @overlay.
Convenience function to set the value of the #GtkOverlay:pass-through child property for @widget.
the main Gtk struct
the main Gtk struct
Get the main Gtk struct
the main Gtk struct as a void*
Gets the child of the #GtkBin, or %NULL if the bin contains no child widget. The returned widget does not have a reference added, so you do not need to unref it.
GtkOverlay is a container which contains a single main child, on top of which it can place “overlay” widgets. The position of each overlay widget is determined by its #GtkWidget:halign and #GtkWidget:valign properties. E.g. a widget with both alignments set to %GTK_ALIGN_START will be placed at the top left corner of the GtkOverlay container, whereas an overlay with halign set to %GTK_ALIGN_CENTER and valign set to %GTK_ALIGN_END will be placed a the bottom edge of the GtkOverlay, horizontally centered. The position can be adjusted by setting the margin properties of the child to non-zero values.
More complicated placement of overlays is possible by connecting to the #GtkOverlay::get-child-position signal.
GtkOverlay as GtkBuildable
The GtkOverlay implementation of the GtkBuildable interface supports placing a child as an overlay by specifying “overlay” as the “type” attribute of a <child> element.
CSS nodes
GtkOverlay has a single CSS node with the name “overlay”. Overlay children whose alignments cause them to be positioned at an edge get the style classes “.left”, “.right”, “.top”, and/or “.bottom” according to their position.