Gtk::SectionModel Class Reference

Interface that adds support for section to list models. More...

#include <gtkmm/sectionmodel.h>

Inheritance diagram for Gtk::SectionModel:

Public Member Functions
	SectionModel (SectionModel &&src) noexcept
SectionModel &	operator= (SectionModel &&src) noexcept
	~SectionModel () noexcept override
GtkSectionModel *	gobj ()
	Provides access to the underlying C GObject.
const GtkSectionModel *	gobj () const
	Provides access to the underlying C GObject.
std::pair< guint, guint >	get_section (guint position) const
	Query the section that covers the given position.
void	sections_changed (guint position, guint n_items)
	This function emits the signal_sections_changed() signal to notify about changes to sections.
Glib::SignalProxy< void(guint, guint)>	signal_sections_changed ()

Static Public Member Functions
static void	add_interface (GType gtype_implementer)
static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system.

Protected Member Functions
	SectionModel ()
	You should derive from this class to use it.
virtual void	get_section_vfunc (guint position, guint &out_start, guint &out_end)
	Return the section that covers the given position.

Related Symbols
(Note that these are not member symbols.)
Glib::RefPtr< Gtk::SectionModel >	wrap (GtkSectionModel *object, bool take_copy=false)
	A Glib::wrap() method for this object.

Detailed Description

Interface that adds support for section to list models.

This support is then used by widgets using list models to be able to group their items into sections.

Many GTK list models support sections inherently, or they pass through the sections of a model they are wrapping.

A Gtk::SectionModel groups successive items into so-called sections. List widgets like Gtk::ListView then allow displaying section headers for these sections.

When the section groupings of a model changes, the model will emit signal_sections_changed() by calling the sections_changed() function. All sections in the given range now need to be queried again.
Gio::ListModel::signal_items_changed() has the same effect, all sections in that range are invalidated, too.

See also

Gio::ListModel, Gtk::ListView

Since gtkmm 4.12:

Constructor & Destructor Documentation

SectionModel() [1/2]

Gtk::SectionModel::SectionModel ( )

protected

You should derive from this class to use it.

SectionModel() [2/2]

Gtk::SectionModel::SectionModel ( SectionModel &&  src )

noexcept

~SectionModel()

Gtk::SectionModel::~SectionModel ( )

overridenoexcept

Member Function Documentation

add_interface()

static void Gtk::SectionModel::add_interface ( GType  gtype_implementer )

static

get_section()

std::pair< guint, guint > Gtk::SectionModel::get_section

(

guint

position

)

const

Query the section that covers the given position.

The number of items in the section can be computed by out_end - out_start.

If the position is larger than the number of items, a single range from n_items to G_MAXUINT will be returned.

Since gtkmm 4.12:

Parameters

position

The position of the item to query.

Returns

{out_start, out_end} The position of the first item in the section, and the position of the first item not part of the section anymore.

get_section_vfunc()

virtual void Gtk::SectionModel::get_section_vfunc ( guint  position, guint &  out_start, guint &  out_end  )

protectedvirtual

Return the section that covers the given position.

If the position is outside the number of items, returns a single range from n_items to G_MAXUINT.

get_type()

static GType Gtk::SectionModel::get_type ( )

static

Get the GType for this class, for use with the underlying GObject type system.

gobj() [1/2]

GtkSectionModel * Gtk::SectionModel::gobj ( )

inline

Provides access to the underlying C GObject.

gobj() [2/2]

const GtkSectionModel * Gtk::SectionModel::gobj ( ) const

inline

Provides access to the underlying C GObject.

operator=()

SectionModel & Gtk::SectionModel::operator= ( SectionModel &&  src )

noexcept

sections_changed()

void Gtk::SectionModel::sections_changed	(	guint	position,
		guint	n_items
	)

This function emits the signal_sections_changed() signal to notify about changes to sections.

It must cover all positions that used to be a section start or that are now a section start. It does not have to cover all positions for which the section has changed.

The Gio::ListModel::signal_items_changed() implies the effect of the signal_sections_changed() signal for all the items it covers.

It is recommended that when changes to the items cause section changes in a larger range, that the larger range is included in the emission of the Gio::ListModel::signal_items_changed() instead of emitting two signals.

Since gtkmm 4.12:

Parameters

position	The first changed item.
n_items	The number of changed items.

signal_sections_changed()

Glib::SignalProxy< void(guint, guint)> Gtk::SectionModel::signal_sections_changed

(

)

Slot Prototype:

void on_my_sections_changed(guint position, guint n_items)

Flags: Run Last

Emitted when the start-of-section state of some of the items in model changes.

Note that this signal does not specify the new section state of the items, they need to be queried manually. It is also not necessary for a model to change the section state of any of the items in the section model, though it would be rather useless to emit such a signal.

The Gio::ListModel::signal_items_changed() implies the effect of the signal_sections_changed() signal for all the items it covers.

Since gtkmm 4.12:

Parameters

position	The first item that may have changed.
n_items	Number of items with changes.

Friends And Related Symbol Documentation

wrap()

Glib::RefPtr< Gtk::SectionModel > wrap ( GtkSectionModel *  object, bool  take_copy = false  )

related

A Glib::wrap() method for this object.

Parameters

object	The C instance.
take_copy	False if the result should take ownership of the C instance. True if it should take a new copy or ref.

Returns

A C++ instance that wraps this C instance.