Expander

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 any other descendant of #GtkBin; you create the child widget and use gtk_container_add() to add it to the expander. When the expander is toggled, it will take care of showing and hiding the child automatically.

Special Usage

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 #GtkExpander:expanded property which can be used to monitor its expansion state. You should watch this property with a signal connection as follows:

|[ expander = gtk_expander_new_with_mnemonic ("_More Options"); g_signal_connect (expander, "notify::expanded", G_CALLBACK (expander_callback), NULL);

...

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 } } ]|

GtkExpander as GtkBuildable

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: |[ <object class="GtkExpander"> <child type="label"> <object class="GtkLabel" id="expander-label"/> </child> <child> <object class="GtkEntry" id="expander-content"/> </child> </object> ]|

CSS nodes

|[ expander ├── title │ ├── arrow │ ╰── <label widget> ╰── <child> ]|

GtkExpander has three CSS nodes, the main node with the name expander, a subnode with name title and node below it with name arrow. Neither of them is using any style classes.

class Expander : Bin {

protected

GtkExpander* gtkExpander;

GtkExpander* getExpanderStruct();

void* getStruct();

void setStruct(GObject* obj);

this(GtkExpander* gtkExpander, bool ownedRef);

this(string label, bool mnemonic);

static GType getType();

bool getExpanded();

string getLabel();

bool getLabelFill();

Widget getLabelWidget();

bool getResizeToplevel();

int getSpacing();

bool getUseMarkup();

bool getUseUnderline();

void setExpanded(bool expanded);

void setLabel(string label);

void setLabelFill(bool labelFill);

void setLabelWidget(Widget labelWidget);

void setResizeToplevel(bool resizeToplevel);

void setSpacing(int spacing);

void setUseMarkup(bool useMarkup);

void setUseUnderline(bool useUnderline);

int[string] connectedSignals;

void delegate(Expander)[] onActivateListeners;

void addOnActivate(void delegate(Expander) dlg, ConnectFlags connectFlags);

static void callBackActivate(GtkExpander* expanderStruct, Expander _expander);

}

Constructors

this this(GtkExpander* gtkExpander, bool ownedRef): Sets our main struct and passes it to the parent class.
this this(string label, bool mnemonic): Creates a new expander using label as the text of the label. Since 2.4

Members

Functions

addOnActivate void addOnActivate(void delegate(Expander) dlg, ConnectFlags connectFlags)
getExpanded bool getExpanded(): Queries a #GtkExpander and returns its current state. Returns %TRUE if the child widget is revealed.
getExpanderStruct GtkExpander* getExpanderStruct(): Get the main Gtk struct
getLabel string getLabel(): 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.
getLabelFill bool getLabelFill(): Returns whether the label widget will fill all available horizontal space allocated to @expander.
getLabelWidget Widget getLabelWidget(): Retrieves the label widget for the frame. See gtk_expander_set_label_widget().
getResizeToplevel bool getResizeToplevel(): Returns whether the expander will resize the toplevel widget containing the expander upon resizing and collpasing.
getSpacing int getSpacing(): Gets the value set by gtk_expander_set_spacing().
getStruct void* getStruct(): the main Gtk struct as a void*
getUseMarkup bool getUseMarkup(): Returns whether the label’s text is interpreted as marked up with the [Pango text markup language]PangoMarkupFormat. See gtk_expander_set_use_markup().
getUseUnderline bool getUseUnderline(): Returns whether an embedded underline in the expander label indicates a mnemonic. See gtk_expander_set_use_underline().
setExpanded void setExpanded(bool 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.
setLabel void setLabel(string label): Sets the text of the label of the expander to @label.
setLabelFill void setLabelFill(bool labelFill): Sets whether the label widget should fill all available horizontal space allocated to @expander.
setLabelWidget void setLabelWidget(Widget labelWidget): Set the label widget for the expander. This is the widget that will appear embedded alongside the expander arrow.
setResizeToplevel void setResizeToplevel(bool resizeToplevel): Sets whether the expander will resize the toplevel widget containing the expander upon resizing and collpasing.
setSpacing void setSpacing(int spacing): Sets the spacing field of @expander, which is the number of pixels to place between expander and the child.
setStruct void setStruct(GObject* obj): Undocumented in source. Be warned that the author may not have intended to support it.
setUseMarkup void setUseMarkup(bool useMarkup): Sets whether the text of the label contains markup in [Pango’s text markup language]PangoMarkupFormat. See gtk_label_set_markup().
setUseUnderline void setUseUnderline(bool useUnderline): If true, an underline in the text of the expander label indicates the next character should be used for the mnemonic accelerator key.

Static functions

callBackActivate void callBackActivate(GtkExpander* expanderStruct, Expander _expander): Undocumented in source. Be warned that the author may not have intended to support it.
getType GType getType()

Variables

connectedSignals int[string] connectedSignals;: Undocumented in source.
gtkExpander GtkExpander* gtkExpander;: the main Gtk struct
onActivateListeners void delegate(Expander)[] onActivateListeners;: Undocumented in source.

Inherited Members

From Bin

gtkBin GtkBin* gtkBin;: the main Gtk struct
getBinStruct GtkBin* getBinStruct(): Get the main Gtk struct
getStruct void* getStruct(): the main Gtk struct as a void*
setStruct void setStruct(GObject* obj): Undocumented in source. Be warned that the author may not have intended to support it.
getType GType getType()
getChild Widget getChild(): 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.