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RGtk2 (version 2.20.31)

GtkExpander: GtkExpander

Description

A container which can hide its child

Arguments

Methods and Functions

gtkExpanderNew(label = NULL, show = TRUE) gtkExpanderNewWithMnemonic(label = NULL) gtkExpanderSetExpanded(object, expanded) gtkExpanderGetExpanded(object) gtkExpanderSetSpacing(object, spacing) gtkExpanderGetSpacing(object) gtkExpanderSetLabel(object, label = NULL) gtkExpanderGetLabel(object) gtkExpanderSetUseUnderline(object, use.underline) gtkExpanderGetUseUnderline(object) gtkExpanderSetUseMarkup(object, use.markup) gtkExpanderGetUseMarkup(object) gtkExpanderSetLabelWidget(object, label.widget = NULL) gtkExpanderGetLabelWidget(object) gtkExpander(label = NULL, show = TRUE)

Hierarchy

GObject
   +----GInitiallyUnowned
         +----GtkObject
               +----GtkWidget
                     +----GtkContainer
                           +----GtkBin
                                 +----GtkExpander

Interfaces

GtkExpander implements AtkImplementorIface and GtkBuildable.

Detailed Description

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 gtkContainerAdd 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 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 element. A normal content child can be specified without specifying a type attribute. A UI definition fragment with GtkExpander
expander <- gtkExpanderNewWithMnemonic("_More Options")
gSignalConnect(expander, "notify::expanded", expander_callback) ... expander_callback <- (expander, param_spec, user_data)
{
  if (expander$getExpanded()) {
    # Show or create widgets
  } else {
    # Hide or destroy widgets
  }
}

Structures

Convenient Construction

gtkExpander is the equivalent of gtkExpanderNew.

Signals

Properties

expanded [logical : Read / Write / Construct]
Whether the expander has been opened to reveal the child widget. Default value: FALSE
label [character : * : Read / Write / Construct]
Text of the expander's label. Default value: NULL
label-widget [GtkWidget : * : Read / Write]
A widget to display in place of the usual expander label.
spacing [integer : Read / Write]
Space to put between the label and the child. Allowed values: >= 0 Default value: 0
use-markup [logical : Read / Write / Construct]
The text of the label includes XML markup. See pango_parse_markup(). Default value: FALSE
use-underline [logical : Read / Write / Construct]
If set, an underline in the text indicates the next character should be used for the mnemonic accelerator key. Default value: FALSE

Style Properties

expander-size [integer : Read]
Size of the expander arrow. Allowed values: >= 0 Default value: 10
expander-spacing [integer : Read]
Spacing around expander arrow. Allowed values: >= 0 Default value: 2

References

http://library.gnome.org/devel//gtk/GtkExpander.html