GtkBox

GtkBox — A container for packing widgets in a single row or column

Properties

GtkBaselinePosition baseline-position Read / Write
gboolean homogeneous Read / Write
int spacing Read / Write

Child Properties

gboolean expand Read / Write
gboolean fill Read / Write
GtkPackType pack-type Read / Write
guint padding Read / Write
int position Read / Write

Types and Values

struct GtkBox
struct GtkBoxClass

Object Hierarchy

    GObject
    ╰── GInitiallyUnowned
        ╰── GtkWidget
            ╰── GtkContainer
                ╰── GtkBox
                    ├── GtkAppChooserWidget
                    ├── GtkButtonBox
                    ├── GtkColorChooserWidget
                    ├── GtkColorSelection
                    ├── GtkFileChooserButton
                    ├── GtkFileChooserWidget
                    ├── GtkFontChooserWidget
                    ├── GtkFontSelection
                    ├── GtkHBox
                    ├── GtkInfoBar
                    ├── GtkRecentChooserWidget
                    ├── GtkShortcutsSection
                    ├── GtkShortcutsGroup
                    ├── GtkShortcutsShortcut
                    ├── GtkStackSwitcher
                    ├── GtkStatusbar
                    ╰── GtkVBox

Implemented Interfaces

GtkBox implements AtkImplementorIface, GtkBuildable and GtkOrientable.

Includes

#include <gtk/gtk.h>

Description

The GtkBox widget arranges child widgets into a single row or column, depending upon the value of its “orientation” property. Within the other dimension, all children are allocated the same size. Of course, the “halign” and “valign” properties can be used on the children to influence their allocation.

GtkBox uses a notion of packing. Packing refers to adding widgets with reference to a particular position in a GtkContainer. For a GtkBox, there are two reference positions: the start and the end of the box. For a vertical GtkBox, the start is defined as the top of the box and the end is defined as the bottom. For a horizontal GtkBox the start is defined as the left side and the end is defined as the right side.

Use repeated calls to gtk_box_pack_start() to pack widgets into a GtkBox from start to end. Use gtk_box_pack_end() to add widgets from end to start. You may intersperse these calls and add widgets from both ends of the same GtkBox.

Because GtkBox is a GtkContainer, you may also use gtk_container_add() to insert widgets into the box, and they will be packed with the default values for expand and fill child properties. Use gtk_container_remove() to remove widgets from the GtkBox.

Use gtk_box_set_homogeneous() to specify whether or not all children of the GtkBox are forced to get the same amount of space.

Use gtk_box_set_spacing() to determine how much space will be minimally placed between all children in the GtkBox. Note that spacing is added between the children, while padding added by gtk_box_pack_start() or gtk_box_pack_end() is added on either side of the widget it belongs to.

Use gtk_box_reorder_child() to move a GtkBox child to a different place in the box.

Use gtk_box_set_child_packing() to reset the expand, fill and padding child properties. Use gtk_box_query_child_packing() to query these fields.

CSS nodes

GtkBox uses a single CSS node with name box.

In horizontal orientation, the nodes of the children are always arranged from left to right. So :first-child will always select the leftmost child, regardless of text direction.

Functions

gtk_box_new ()

GtkWidget *
gtk_box_new (GtkOrientation orientation,
             gint spacing);

Creates a new GtkBox.

Parameters

orientation

the box’s orientation.

spacing

the number of pixels to place by default between children.

Returns

a new GtkBox.

Since: 3.0

gtk_box_pack_start ()

void
gtk_box_pack_start (GtkBox *box,
                    GtkWidget *child,
                    gboolean expand,
                    gboolean fill,
                    guint padding);

Adds child to box , packed with reference to the start of box . The child is packed after any other child packed with reference to the start of box .

Parameters

box

a GtkBox

child

the GtkWidget to be added to box

expand

TRUE if the new child is to be given extra space allocated to box . The extra space will be divided evenly between all children that use this option

fill

TRUE if space given to child by the expand option is actually allocated to child , rather than just padding it. This parameter has no effect if expand is set to FALSE. A child is always allocated the full height of a horizontal GtkBox and the full width of a vertical GtkBox. This option affects the other dimension

padding

extra space in pixels to put between this child and its neighbors, over and above the global amount specified by “spacing” property. If child is a widget at one of the reference ends of box , then padding pixels are also put between child and the reference edge of box

gtk_box_pack_end ()

void
gtk_box_pack_end (GtkBox *box,
                  GtkWidget *child,
                  gboolean expand,
                  gboolean fill,
                  guint padding);

Adds child to box , packed with reference to the end of box . The child is packed after (away from end of) any other child packed with reference to the end of box .

Parameters

box

a GtkBox

child

the GtkWidget to be added to box

expand

TRUE if the new child is to be given extra space allocated to box . The extra space will be divided evenly between all children of box that use this option

fill

TRUE if space given to child by the expand option is actually allocated to child , rather than just padding it. This parameter has no effect if expand is set to FALSE. A child is always allocated the full height of a horizontal GtkBox and the full width of a vertical GtkBox. This option affects the other dimension

padding

extra space in pixels to put between this child and its neighbors, over and above the global amount specified by “spacing” property. If child is a widget at one of the reference ends of box , then padding pixels are also put between child and the reference edge of box

gtk_box_get_homogeneous ()

gboolean
gtk_box_get_homogeneous (GtkBox *box);

Returns whether the box is homogeneous (all children are the same size). See gtk_box_set_homogeneous().

Parameters

box

a GtkBox

Returns

TRUE if the box is homogeneous.

gtk_box_set_homogeneous ()

void
gtk_box_set_homogeneous (GtkBox *box,
                         gboolean homogeneous);

Sets the “homogeneous” property of box , controlling whether or not all children of box are given equal space in the box.

Parameters

box

a GtkBox

homogeneous

a boolean value, TRUE to create equal allotments, FALSE for variable allotments

gtk_box_get_spacing ()

gint
gtk_box_get_spacing (GtkBox *box);

Gets the value set by gtk_box_set_spacing().

Parameters

box

a GtkBox

Returns

spacing between children

gtk_box_set_spacing ()

void
gtk_box_set_spacing (GtkBox *box,
                     gint spacing);

Sets the “spacing” property of box , which is the number of pixels to place between children of box .

Parameters

box

a GtkBox

spacing

the number of pixels to put between children

gtk_box_reorder_child ()

void
gtk_box_reorder_child (GtkBox *box,
                       GtkWidget *child,
                       gint position);

Moves child to a new position in the list of box children. The list contains widgets packed GTK_PACK_START as well as widgets packed GTK_PACK_END, in the order that these widgets were added to box .

A widget’s position in the box children list determines where the widget is packed into box . A child widget at some position in the list will be packed just after all other widgets of the same packing type that appear earlier in the list.

Parameters

box

a GtkBox

child

the GtkWidget to move

position

the new position for child in the list of children of box , starting from 0. If negative, indicates the end of the list

gtk_box_query_child_packing ()

void
gtk_box_query_child_packing (GtkBox *box,
                             GtkWidget *child,
                             gboolean *expand,
                             gboolean *fill,
                             guint *padding,
                             GtkPackType *pack_type);

Obtains information about how child is packed into box .

Parameters

box

a GtkBox

child

the GtkWidget of the child to query

expand

pointer to return location for expand child property.

[out]

fill

pointer to return location for fill child property.

[out]

padding

pointer to return location for padding child property.

[out]

pack_type

pointer to return location for pack-type child property.

[out]

gtk_box_set_child_packing ()

void
gtk_box_set_child_packing (GtkBox *box,
                           GtkWidget *child,
                           gboolean expand,
                           gboolean fill,
                           guint padding,
                           GtkPackType pack_type);

Sets the way child is packed into box .

Parameters

box

a GtkBox

child

the GtkWidget of the child to set

expand

the new value of the expand child property

fill

the new value of the fill child property

padding

the new value of the padding child property

pack_type

the new value of the pack-type child property

gtk_box_get_baseline_position ()

GtkBaselinePosition
gtk_box_get_baseline_position (GtkBox *box);

Gets the value set by gtk_box_set_baseline_position().

Parameters

box

a GtkBox

Returns

the baseline position

Since: 3.10

gtk_box_set_baseline_position ()

void
gtk_box_set_baseline_position (GtkBox *box,
                               GtkBaselinePosition position);

Sets the baseline position of a box. This affects only horizontal boxes with at least one baseline aligned child. If there is more vertical space available than requested, and the baseline is not allocated by the parent then position is used to allocate the baseline wrt the extra space available.

Parameters

box

a GtkBox

position

a GtkBaselinePosition

Since: 3.10

gtk_box_get_center_widget ()

GtkWidget *
gtk_box_get_center_widget (GtkBox *box);

Retrieves the center widget of the box.

Parameters

box

a GtkBox

Returns

the center widget or NULL in case no center widget is set.

[transfer none][nullable]

Since: 3.12

gtk_box_set_center_widget ()

void
gtk_box_set_center_widget (GtkBox *box,
                           GtkWidget *widget);

Sets a center widget; that is a child widget that will be centered with respect to the full width of the box, even if the children at either side take up different amounts of space.

Parameters

box

a GtkBox

widget

the widget to center.

[allow-none]

Since: 3.12

Types and Values

struct GtkBox

struct GtkBox;

struct GtkBoxClass

struct GtkBoxClass {
  GtkContainerClass parent_class;
};

Members

Property Details

The “baseline-position” property

  “baseline-position”        GtkBaselinePosition

The position of the baseline aligned widgets if extra space is available.

Owner: GtkBox

Flags: Read / Write

Default value: GTK_BASELINE_POSITION_CENTER

The “homogeneous” property

  “homogeneous”              gboolean

Whether the children should all be the same size.

Owner: GtkBox

Flags: Read / Write

Default value: FALSE

The “spacing” property

  “spacing”                  int

The amount of space between children.

Owner: GtkBox

Flags: Read / Write

Allowed values: >= 0

Default value: 0

Child Property Details

The “expand” child property

  “expand”                   gboolean

Whether the child should receive extra space when the parent grows.

Note that the default value for this property is FALSE for GtkBox, but GtkHBox, GtkVBox and other subclasses use the old default of TRUE.

Note: The “hexpand” or “vexpand” properties are the preferred way to influence whether the child receives extra space, by setting the child’s expand property corresponding to the box’s orientation.

In contrast to “hexpand”, the expand child property does not cause the box to expand itself.

Owner: GtkBox

Flags: Read / Write

Default value: FALSE

The “fill” child property

  “fill”                     gboolean

Whether the child should fill extra space or use it as padding.

Note: The “halign” or “valign” properties are the preferred way to influence whether the child fills available space, by setting the child’s align property corresponding to the box’s orientation to GTK_ALIGN_FILL to fill, or to something else to refrain from filling.

Owner: GtkBox

Flags: Read / Write

Default value: TRUE

The “pack-type” child property

  “pack-type”                GtkPackType

A GtkPackType indicating whether the child is packed with reference to the start or end of the parent.

Owner: GtkBox

Flags: Read / Write

Default value: GTK_PACK_START

The “padding” child property

  “padding”                  guint

Extra space to put between the child and its neighbors, in pixels.

Note: The CSS padding properties are the preferred way to add space among widgets, by setting the paddings corresponding to the box’s orientation.

Owner: GtkBox

Flags: Read / Write

Allowed values: <= G_MAXINT

Default value: 0

The “position” child property

  “position”                 int

The index of the child in the parent.

Owner: GtkBox

Flags: Read / Write

Allowed values: >= -1

Default value: 0

See Also

GtkGrid

© 2005–2020 The GNOME Project
Licensed under the GNU Lesser General Public License version 2.1 or later.
https://developer.gnome.org/gtk3/3.24/GtkBox.html