GtkScrolledWindow

GtkScrolledWindow — Adds scrollbars to its child widget

Includes

#include <gtk/gtk.h>

Description

GtkScrolledWindow is a GtkBin subclass: it's a container the accepts a single child widget. GtkScrolledWindow adds scrollbars to the child widget and optionally draws a beveled frame around the child widget.

The scrolled window can work in two ways. Some widgets have native scrolling support; these widgets have "slots" for GtkAdjustment objects. [5] Widgets with native scroll support include GtkTreeView, GtkTextView, and GtkLayout.

For widgets that lack native scrolling support, the GtkViewport widget acts as an adaptor class, implementing scrollability for child widgets that lack their own scrolling capabilities. Use GtkViewport to scroll child widgets such as GtkTable, GtkBox, and so on.

If a widget has native scrolling abilities, it can be added to the GtkScrolledWindow with gtk_container_add(). If a widget does not, you must first add the widget to a GtkViewport, then add the GtkViewport to the scrolled window. The convenience function gtk_scrolled_window_add_with_viewport() does exactly this, so you can ignore the presence of the viewport.

The position of the scrollbars is controlled by the scroll adjustments. See GtkAdjustment for the fields in an adjustment - for GtkScrollbar, used by GtkScrolledWindow, the "value" field represents the position of the scrollbar, which must be between the "lower" field and "upper - page_size." The "page_size" field represents the size of the visible scrollable area. The "step_increment" and "page_increment" fields are used when the user asks to step down (using the small stepper arrows) or page down (using for example the PageDown key).

If a GtkScrolledWindow doesn't behave quite as you would like, or doesn't have exactly the right layout, it's very possible to set up your own scrolling with GtkScrollbar and for example a GtkTable.

Functions

Types and Values

See Also

GtkViewport, GtkAdjustment, GtkWidgetClass



[5] The scrolled window installs GtkAdjustment objects in the child window's slots using the set_scroll_adjustments_signal, found in GtkWidgetClass. (Conceptually, these widgets implement a "Scrollable" interface; because GTK+ 1.2 lacked interface support in the object system, this interface is hackily implemented as a signal in GtkWidgetClass. The GTK+ 2.0 object system would allow a clean implementation, but it wasn't worth breaking the API.)