Gtk.SectionModel

interface

An interface that adds support for sections to list models.

A GtkSectionModel groups successive items into so-called sections. List widgets like GtkListView and GtkGridView then allow displaying section headers for these sections by installing a header factory.

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

When the section groupings of a model change, the model will emit the SectionModel.sections-changed signal by calling the SectionModel.sections_changed function. All sections in the given range then need to be queried again. The Gio.ListModel.items-changed signal has the same effect, all sections in that range are invalidated, too.

Methods

get_section

def get_section(self, position: int) -> tuple[int, int]

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.

Parameters:

• position — the position of the item to query

sections_changed

def sections_changed(self, position: int, n_items: int) -> None

This function emits the SectionModel.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.items-changed implies the effect of the SectionModel.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.items-changed instead of emitting two signals.

Parameters:

• position — the first changed item
• n_items — the number of changed items

Virtual methods

do_get_section

def do_get_section(self, position: int) -> tuple[int, int]

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.

Parameters:

• position — the position of the item to query

Signals

sections-changed

def on_sections_changed(self, position: int, n_items: int) -> None: ...

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.items-changed implies the effect of the SectionModel.sections-changed signal for all the items it covers.