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Package Gtk.Scrolled_Window

Gtk_Scrolled_Window is a Gtk_Bin child: it's a container the accepts a single child widget. Gtk_Scrolled_Window adds scrollbars to the child widget.

The scrolled window can work in two ways. Some widgets have native scrolling support; these widgets have "slots" for Gtk_Adjustment objects. The scrolled window installs Gtk_Adjustment objects in the child window's slots using the "set_scroll_adjustments" signal (Conceptually, these widgets implement a "Scrollable" interface).

The second way to use the scrolled window is useful with widgets that lack the "set_scroll_adjustments" signal. The Gtk_Viewport widget acts as a proxy, implementing scrollability for child widgets that lack their own scrolling capabilities.

If a widget has native scrolling abilities, it can be added to the Gtk_Scrolled_Window with Gtk.Container.Add. If a widget does not, you must first add the widget to a Gtk_Viewport, then add the Gtk_Viewport to the scrolled window. The convenience function Add_With_Viewport does exactly this, so you can ignore the presence of the viewport.

If you want to create your own new widget type that can be inserted directly into a scrolled_window, you need to specify a signal for Set_Scroll_Adjustments in the call to Gtk.Object.Initialize_Class_Record.

Widget Hierarchy
     GObject                       (see Package_Glib.Object)
     Gtk_Object                    (see Package_Gtk.Object)
        \___ Gtk_Widget            (see Package_Gtk.Widget)
           \___ Gtk_Container      (see Package_Gtk.Container)
              \___ Gtk_Bin         (see Package_Gtk.Bin)
                 \___ Gtk_Scrolled_Window (see Package_Gtk.Scrolled_Window)
     

Subprograms
procedure Gtk_New (Scrolled_Window : out Gtk_Scrolled_Window; Hadjustment : Gtk_Adjustment := Null_Adjustment; Vadjustment : Gtk_Adjustment := Null_Adjustment);
Create a new scrolled window.
The two arguments are the scrolled window's horizontal and vertical adjustments; these will be shared with the scrollbars and the child widget to keep the bars in sync with the child. Usually you want to use the default value Null_Adjustment for the adjustments, which will cause the scrolled window to create them for you.

function Get_Type return Gtk.Gtk_Type;
Return the internal value associated with a Gtk_Scrolled_Window.

procedure Set_Hadjustment (Scrolled_Window : access Gtk_Scrolled_Window_Record; Hadjustment : Gtk_Adjustment);
Set the Gtk_Adjustment for the horizontal scrollbar.

procedure Set_Vadjustment (Scrolled_Window : access Gtk_Scrolled_Window_Record; Vadjustment : Gtk_Adjustment);
Set the Gtk_Adjustment for the vertical scrollbar.

function Get_Hadjustment (Scrolled_Window : access Gtk_Scrolled_Window_Record) return Gtk_Adjustment;
Return the horizontal scrollbar's adjustment.
This adjustment is used to connect the horizontal scrollbar to the child widget's horizontal scroll functionality.

function Get_Vadjustment (Scrolled_Window : access Gtk_Scrolled_Window_Record) return Gtk_Adjustment;
Return the vertical scrollbar's adjustment.
This adjustment is used to connect the vertical scrollbar to the child widget's vertical scroll functionality.

procedure Set_Policy (Scrolled_Window : access Gtk_Scrolled_Window_Record; H_Scrollbar_Policy : Enums.Gtk_Policy_Type; V_Scrollbar_Policy : Enums.Gtk_Policy_Type);
Set the scrollbar policy for the horizontal and vertical scrollbars.
It determines when the scrollbar should appear; it is a value from the Gtk_Policy_Type enumeration. If Policy_Always, the scrollbar is always present; if Policy_Never, the scrollbar is never present; if Policy_Automatic, the scrollbar is present only if needed (that is, if the slider part of the bar would be smaller than the trough - the display is larger than the page size).

procedure Get_Policy (Scrolled_Window : access Gtk_Scrolled_Window_Record; H_Scrollbar_Policy : out Enums.Gtk_Policy_Type; V_Scrollbar_Policy : out Enums.Gtk_Policy_Type);
Return the scrollbar policy for the horizontal and vertical scrollbars.

procedure Set_Placement (Scrolled_Window : access Gtk_Scrolled_Window_Record; Window_Placement : Gtk.Enums.Gtk_Corner_Type);
Determine the location of the widget with respect to the scrollbars.
The default is Corner_Top_Left.

function Get_Placement (Scrolled_Window : access Gtk_Scrolled_Window_Record) return Gtk.Enums.Gtk_Corner_Type;
Return the location of the widget with respect to the scrollbars.

procedure Set_Shadow_Type (Scrolled_Window : access Gtk_Scrolled_Window_Record; Shadow_Type : Gtk.Enums.Gtk_Shadow_Type);
Change the type of shadow drawn around the contents of Scrolled_Window.

function Get_Shadow_Type (Scrolled_Window : access Gtk_Scrolled_Window_Record) return Gtk.Enums.Gtk_Shadow_Type;
Return the type of shadow drawn around the contents of Scrolled_Window.

procedure Add_With_Viewport (Scrolled_Window : access Gtk_Scrolled_Window_Record; Child : access Gtk.Widget.Gtk_Widget_Record'Class);
Used to add children without native scrolling capabilities.
This is simply a convenience function; it is equivalent to adding the unscrollable child to a viewport, then adding the viewport to the scrolled window. If a child has native scrolling, use Gtk.Container.Add instead of this function.

The viewport scrolls the child by moving its Gdk_Window, and takes the size of the child to be the size of its toplevel Gdk_Window. This will be very wrong for most widgets that support native scrolling; for example, if you add a Gtk_Clist with a viewport, the whole widget will scroll, including the column headings. Thus Gtk_Clist supports scrolling already, and should not be used with the GtkViewport proxy.

A widget supports scrolling natively if it contains a valid "set_scroll_adjustments" signal.