Struct gtk4::SelectionModel

pub struct SelectionModel { /* private fields */ }

SelectionModel is an interface that add support for selection to list models.

This support is then used by widgets using list models to add the ability to select and unselect various items.

GTK provides default implementations of the most common selection modes such as SingleSelection, so you will only need to implement this interface if you want detailed control about how selections should be handled.

A SelectionModel supports a single boolean per item indicating if an item is selected or not. This can be queried via SelectionModelExt::is_selected(). When the selected state of one or more items changes, the model will emit the selection-changed signal by calling the SelectionModelExt::selection_changed() function. The positions given in that signal may have their selection state changed, though that is not a requirement. If new items added to the model via the items-changed signal are selected or not is up to the implementation.

Note that items added via items-changed may already be selected and no selection-changed will be emitted for them. So to track which items are selected, it is necessary to listen to both signals.

Additionally, the interface can expose functionality to select and unselect items. If these functions are implemented, GTK’s list widgets will allow users to select and unselect items. However, SelectionModels are free to only implement them partially or not at all. In that case the widgets will not support the unimplemented operations.

When selecting or unselecting is supported by a model, the return values of the selection functions do not indicate if selection or unselection happened. They are only meant to indicate complete failure, like when this mode of selecting is not supported by the model.

Selections may happen asynchronously, so the only reliable way to find out when an item was selected is to listen to the signals that indicate selection.

Signals

selection-changed

Emitted when the selection state of some of the items in @model changes.

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

ListModel

items-changed

This signal is emitted whenever items were added to or removed from @list. At @position, @removed items were removed and @added items were added in their place.

Note: If removed != added, the positions of all later items in the model change.

Implements

SelectionModelExt, gio::prelude::ListModelExt

Implementations

impl SelectionModel

pub const NONE: Option<&'static SelectionModel> = None

Trait Implementations

impl Clone for SelectionModel

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SelectionModel

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl HasParamSpec for SelectionModel

type ParamSpec = ParamSpecObject

type SetValue = SelectionModel

Preferred value to be used as setter for the associated ParamSpec.

type BuilderFn = fn(_: &str) -> ParamSpecObjectBuilder<'_, SelectionModel>

fn param_spec_builder() -> Self::BuilderFn

impl Hash for SelectionModel

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T: SelectionModelImpl> IsImplementable<T> for SelectionModel

fn interface_init(iface: &mut Interface<Self>)

Override the virtual methods of this interface for the given subclass and do other interface initialization.

fn instance_init(_instance: &mut InitializingObject<T>)

Instance specific initialization.

impl Ord for SelectionModel

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl<OT: ObjectType> PartialEq<OT> for SelectionModel

fn eq(&self, other: &OT) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<OT: ObjectType> PartialOrd<OT> for SelectionModel

fn partial_cmp(&self, other: &OT) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for SelectionModel

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for SelectionModel

impl IsA<ListModel> for SelectionModel

impl IsA<SelectionModel> for MultiSelection

impl IsA<SelectionModel> for NoSelection

impl IsA<SelectionModel> for SingleSelection