Interface SectionModel<T extends GObject>

All Superinterfaces:

Collection<T>, Iterable<T>, List<T>, ListModel<T>, ListModelJavaList<T>, Proxy, SequencedCollection<T>

All Known Implementing Classes:

FilterListModel, FlattenListModel, MapListModel, MultiSelection, NoSelection, SectionModel.SectionModel$Impl, SingleSelection, SliceListModel, SortListModel, ViewStackPages

@Generated("org.javagi.JavaGI")
public interface SectionModel<T extends GObject>
extends Proxy, ListModel<T>

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 Gtk.SectionModel::sections-changed signal by calling the sectionsChanged(int, int) 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.

Since:

4.12

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	SectionModel.SectionModel$Impl	The SectionModel$Impl type represents a native instance of the SectionModel interface.
static class	SectionModel.SectionModelInterface	The list of virtual functions for the GtkSectionModel interface.
static interface	SectionModel.SectionsChangedCallback	Functional interface declaration of the SectionsChangedCallback callback.

Nested classes/interfaces inherited from interface ListModel

ListModel.ItemsChangedCallback, ListModel.ListModel$Impl, ListModel.ListModelInterface

Nested classes/interfaces inherited from interface ListModelJavaList

ListModelJavaList.SubList<E,List>

Method Summary

Modifier and Type	Method	Description
default void	emitSectionsChanged(int position, int nItems)	Emits the "sections-changed" signal.
default void	getSection(int position, Out<Integer> outStart, Out<Integer> outEnd)	Query the section that covers the given position.
static @Nullable Type	getType()	Get the GType of the SectionModel class.
default SignalConnection<SectionModel.SectionsChangedCallback>	onSectionsChanged(SectionModel.SectionsChangedCallback handler)	Emitted when the start-of-section state of some of the items in model changes.
default void	sectionsChanged(int position, int nItems)	This function emits the Gtk.SectionModel::sections-changed signal to notify about changes to sections.

Methods inherited from interface Collection

parallelStream, removeIf, stream, toArray

Methods inherited from interface Iterable

forEach

Methods inherited from interface List

addFirst, addLast, equals, getFirst, getLast, hashCode, removeFirst, removeLast, replaceAll, reversed, sort, spliterator

Methods inherited from interface ListModel

emitItemsChanged, getItem, getItemType, getNItems, itemsChanged, onItemsChanged

Methods inherited from interface ListModelJavaList

add, add, addAll, addAll, clear, contains, containsAll, get, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, retainAll, set, size, subList, toArray, toArray

Methods inherited from interface Proxy

handle

Method Details

getType

static @Nullable Type getType()

Get the GType of the SectionModel class.

Returns:

the GType

getSection

default void getSection(int position,
 Out<Integer> outStart,
 Out<Integer> outEnd)

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

outStart - the position of the first item in the section

outEnd - the position of the first item not part of the section anymore.

Since:

4.12

sectionsChanged

default void sectionsChanged(int position,
 int nItems)

This function emits the Gtk.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 Gtk.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

nItems - the number of changed items

Since:

4.12

onSectionsChanged

default SignalConnection<SectionModel.SectionsChangedCallback> onSectionsChanged(SectionModel.SectionsChangedCallback handler)

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 Gtk.SectionModel::sections-changed signal for all the items it covers.

Parameters:

handler - the signal handler

Returns:

a signal handler ID to keep track of the signal connection

Since:

4.12

See Also:

• SectionModel.SectionsChangedCallback.run(int, int)

emitSectionsChanged

default void emitSectionsChanged(int position,
 int nItems)

Emits the "sections-changed" signal. See onSectionsChanged(SectionModel.SectionsChangedCallback).