GtkExpander — A container which can hide its child
GtkWidget * | gtk_expander_new () |
GtkWidget * | gtk_expander_new_with_mnemonic () |
void | gtk_expander_set_expanded () |
gboolean | gtk_expander_get_expanded () |
void | gtk_expander_set_label () |
const char * | gtk_expander_get_label () |
void | gtk_expander_set_use_underline () |
gboolean | gtk_expander_get_use_underline () |
void | gtk_expander_set_use_markup () |
gboolean | gtk_expander_get_use_markup () |
void | gtk_expander_set_label_widget () |
GtkWidget * | gtk_expander_get_label_widget () |
void | gtk_expander_set_resize_toplevel () |
gboolean | gtk_expander_get_resize_toplevel () |
void | gtk_expander_set_child () |
GtkWidget * | gtk_expander_get_child () |
GtkWidget * | child | Read / Write |
gboolean | expanded | Read / Write / Construct |
char * | label | Read / Write / Construct |
GtkWidget * | label-widget | Read / Write |
gboolean | resize-toplevel | Read / Write |
gboolean | use-markup | Read / Write / Construct |
gboolean | use-underline | Read / Write / Construct |
void | activate | Action |
GObject ╰── GInitiallyUnowned ╰── GtkWidget ╰── GtkExpander
GtkExpander implements GtkAccessible, GtkBuildable and GtkConstraintTarget.
#include <gtk/gtk.h>
A GtkExpander allows the user to hide or show its child by clicking on an expander triangle similar to the triangles used in a GtkTreeView.
Normally you use an expander as you would use a frame; you create the child widget and use gtk_expander_set_child()
to add it to the expander. When the expander is toggled, it will take care of showing and hiding the child automatically.
There are situations in which you may prefer to show and hide the expanded widget yourself, such as when you want to actually create the widget at expansion time. In this case, create a GtkExpander but do not add a child to it. The expander widget has an “expanded” property which can be used to monitor its expansion state. You should watch this property with a signal connection as follows:
The GtkExpander implementation of the GtkBuildable interface supports placing a child in the label position by specifying “label” as the “type” attribute of a <child> element. A normal content child can be specified without specifying a <child> type attribute.
An example of a UI definition fragment with GtkExpander:
static void expander_callback (GObject *object, GParamSpec *param_spec, gpointer user_data) { GtkExpander *expander; expander = GTK_EXPANDER (object); if (gtk_expander_get_expanded (expander)) { // Show or create widgets } else { // Hide or destroy widgets } } static void create_expander (void) { GtkWidget *expander = gtk_expander_new_with_mnemonic ("_More Options"); g_signal_connect (expander, "notify::expanded", G_CALLBACK (expander_callback), NULL); // ... }
GtkExpander has three CSS nodes, the main node with the name expander, a subnode with name title and node below it with name arrow. The arrow of an expander that is showing its child gets the :checked pseudoclass added to it.
GtkExpander uses the GTK_ACCESSIBLE_ROLE_BUTTON role.
GtkWidget *
gtk_expander_new (const char *label
);
Creates a new expander using label
as the text of the label.
label | the text of the label. | [nullable] |
a new GtkExpander widget.
GtkWidget *
gtk_expander_new_with_mnemonic (const char *label
);
Creates a new expander using label
as the text of the label. If characters in label
are preceded by an underscore, they are underlined. If you need a literal underscore character in a label, use “__” (two underscores). The first underlined character represents a keyboard accelerator called a mnemonic. Pressing Alt and that key activates the button.
label | the text of the label with an underscore in front of the mnemonic character. | [nullable] |
a new GtkExpander widget.
void gtk_expander_set_expanded (GtkExpander *expander
,gboolean expanded
);
Sets the state of the expander. Set to TRUE
, if you want the child widget to be revealed, and FALSE
if you want the child widget to be hidden.
expander | ||
expanded | whether the child widget is revealed |
gboolean
gtk_expander_get_expanded (GtkExpander *expander
);
Queries a GtkExpander and returns its current state. Returns TRUE
if the child widget is revealed.
See gtk_expander_set_expanded()
.
expander |
the current state of the expander
void gtk_expander_set_label (GtkExpander *expander
,const char *label
);
Sets the text of the label of the expander to label
.
This will also clear any previously set labels.
expander | ||
label | a string. | [nullable] |
const char *
gtk_expander_get_label (GtkExpander *expander
);
Fetches the text from a label widget including any embedded underlines indicating mnemonics and Pango markup, as set by gtk_expander_set_label()
. If the label text has not been set the return value will be NULL
. This will be the case if you create an empty button with gtk_button_new()
to use as a container.
Note that this function behaved differently in versions prior to 2.14 and used to return the label text stripped of embedded underlines indicating mnemonics and Pango markup. This problem can be avoided by fetching the label text directly from the label widget.
expander |
The text of the label widget. This string is owned by the widget and must not be modified or freed.
[nullable]
void gtk_expander_set_use_underline (GtkExpander *expander
,gboolean use_underline
);
If true, an underline in the text of the expander label indicates the next character should be used for the mnemonic accelerator key.
expander | ||
use_underline |
|
gboolean
gtk_expander_get_use_underline (GtkExpander *expander
);
Returns whether an embedded underline in the expander label indicates a mnemonic. See gtk_expander_set_use_underline()
.
expander |
TRUE
if an embedded underline in the expander label indicates the mnemonic accelerator keys
void gtk_expander_set_use_markup (GtkExpander *expander
,gboolean use_markup
);
Sets whether the text of the label contains markup in Pango’s text markup language. See gtk_label_set_markup()
.
expander | ||
use_markup |
|
gboolean
gtk_expander_get_use_markup (GtkExpander *expander
);
Returns whether the label’s text is interpreted as marked up with the Pango text markup language. See gtk_expander_set_use_markup()
.
expander |
TRUE
if the label’s text will be parsed for markup
void gtk_expander_set_label_widget (GtkExpander *expander
,GtkWidget *label_widget
);
Set the label widget for the expander. This is the widget that will appear embedded alongside the expander arrow.
expander | ||
label_widget | the new label widget. | [nullable] |
GtkWidget *
gtk_expander_get_label_widget (GtkExpander *expander
);
Retrieves the label widget for the frame. See gtk_expander_set_label_widget()
.
expander |
the label widget, or NULL
if there is none.
[nullable][transfer none]
void gtk_expander_set_resize_toplevel (GtkExpander *expander
,gboolean resize_toplevel
);
Sets whether the expander will resize the toplevel widget containing the expander upon resizing and collpasing.
expander | ||
resize_toplevel | whether to resize the toplevel |
gboolean
gtk_expander_get_resize_toplevel (GtkExpander *expander
);
Returns whether the expander will resize the toplevel widget containing the expander upon resizing and collpasing.
expander |
the “resize toplevel” setting.
void gtk_expander_set_child (GtkExpander *expander
,GtkWidget *child
);
Sets the child widget of expander
.
expander | ||
child | the child widget. | [allow-none] |
GtkWidget *
gtk_expander_get_child (GtkExpander *expander
);
Gets the child widget of expander
.
expander |
the child widget of expander
.
[nullable][transfer none]
typedef struct _GtkExpander GtkExpander;
“expanded”
property“expanded” gboolean
Whether the expander has been opened to reveal the child widget.
Owner: GtkExpander
Flags: Read / Write / Construct
Default value: FALSE
“label”
property“label” char *
Text of the expander’s label.
Owner: GtkExpander
Flags: Read / Write / Construct
Default value: NULL
“label-widget”
property“label-widget” GtkWidget *
A widget to display in place of the usual expander label.
Owner: GtkExpander
Flags: Read / Write
“resize-toplevel”
property“resize-toplevel” gboolean
When this property is TRUE
, the expander will resize the toplevel widget containing the expander upon expanding and collapsing.
Owner: GtkExpander
Flags: Read / Write
Default value: FALSE
“use-markup”
property“use-markup” gboolean
The text of the label includes XML markup. See pango_parse_markup().
Owner: GtkExpander
Flags: Read / Write / Construct
Default value: FALSE
“use-underline”
property“use-underline” gboolean
If set, an underline in the text indicates the next character should be used for the mnemonic accelerator key.
Owner: GtkExpander
Flags: Read / Write / Construct
Default value: FALSE
“activate”
signalvoid user_function (GtkExpander *expander, gpointer user_data)
Activates the GtkExpander.
expander | the GtkExpander that emitted the signal | |
user_data | user data set when the signal handler was connected. |
Flags: Action
© 2005–2020 The GNOME Project
Licensed under the GNU Lesser General Public License version 2.1 or later.
https://developer.gnome.org/gtk4/4.0/GtkExpander.html