Struct gtk4::TreeExpander

#[repr(transparent)]
pub struct TreeExpander { /* private fields */ }

TreeExpander is a widget that provides an expander for a list.

It is typically placed as a bottommost child into a ListView to allow users to expand and collapse children in a list with a TreeListModel. TreeExpander provides the common UI elements, gestures and keybindings for this purpose.

On top of this, the “listitem.expand”, “listitem.collapse” and “listitem.toggle-expand” actions are provided to allow adding custom UI for managing expanded state.

The TreeListModel must be set to not be passthrough. Then it will provide TreeListRow items which can be set via set_list_row() on the expander. The expander will then watch that row item automatically. set_child() sets the widget that displays the actual row contents.

TreeExpander can be modified with properties such as property::TreeExpander::indent-for-icon, property::TreeExpander::indent-for-depth, and property::TreeExpander::hide-expander to achieve a different appearance. This can even be done to influence individual rows, for example by binding the property::TreeExpander::hide-expander property to the item count of the model of the treelistrow, to hide the expander for rows without children, even if the row is expandable.

CSS nodes

treeexpander
├── [indent]*
├── [expander]
╰── <child>

TreeExpander has zero or one CSS nodes with the name “expander” that should display the expander icon. The node will be :checked when it is expanded. If the node is not expandable, an “indent” node will be displayed instead.

For every level of depth, another “indent” node is prepended.

Accessibility

TreeExpander uses the AccessibleRole::Group role. The expander icon is represented as a AccessibleRole::Button, labelled by the expander’s child, and toggling it will change the AccessibleState::Expanded state.

Implements

WidgetExt, glib::ObjectExt, AccessibleExt, BuildableExt, ConstraintTargetExt, WidgetExtManual, AccessibleExtManual

Implementations

impl TreeExpander

pub fn new() -> TreeExpander

Creates a new TreeExpander

Returns

a new TreeExpander

pub fn builder() -> TreeExpanderBuilder

Creates a new builder-pattern struct instance to construct TreeExpander objects.

This method returns an instance of TreeExpanderBuilder which can be used to create TreeExpander objects.

pub fn child(&self) -> Option<Widget>

Gets the child widget displayed by @self.

Returns

The child displayed by @self

pub fn hides_expander(&self) -> bool

Available on crate feature v4_10 only.

Gets whether the TreeExpander should be hidden in a GtkTreeListRow.

Returns

TRUE if the expander icon should be hidden. Otherwise FALSE.

pub fn is_indent_for_depth(&self) -> bool

Available on crate feature v4_10 only.

TreeExpander indents each level of depth with an additional indent.

Returns

TRUE if the child should be indented . Otherwise FALSE.

pub fn is_indent_for_icon(&self) -> bool

Available on crate feature v4_6 only.

TreeExpander indents the child by the width of an expander-icon if it is not expandable.

Returns

TRUE if the child should be indented when not expandable. Otherwise FALSE.

pub fn item(&self) -> Option<Object>

Forwards the item set on the TreeListRow that @self is managing.

This call is essentially equivalent to calling:

⚠️ The following code is in c ⚠️

gtk_tree_list_row_get_item (gtk_tree_expander_get_list_row (@self));

Returns

The item of the row

pub fn list_row(&self) -> Option<TreeListRow>

Gets the list row managed by @self.

Returns

The list row displayed by @self

pub fn set_child(&self, child: Option<&impl IsA<Widget>>)

Sets the content widget to display.

child

a Widget

pub fn set_hide_expander(&self, hide_expander: bool)

Available on crate feature v4_10 only.

Sets whether the expander icon should be visible in a GtkTreeListRow.

hide_expander

TRUE if the expander should be hidden. Otherwise FALSE.

pub fn set_indent_for_depth(&self, indent_for_depth: bool)

Available on crate feature v4_10 only.

Sets if the TreeExpander should indent the child according to its depth.

indent_for_depth

TRUE if the child should be indented. Otherwise FALSE.

pub fn set_indent_for_icon(&self, indent_for_icon: bool)

Available on crate feature v4_6 only.

Sets if the TreeExpander should indent the child by the width of an expander-icon when it is not expandable.

indent_for_icon

TRUE if the child should be indented without expander. Otherwise FALSE.

pub fn set_list_row(&self, list_row: Option<&TreeListRow>)

Sets the tree list row that this expander should manage.

list_row

a TreeListRow

pub fn connect_child_notify<F: Fn(&Self) + 'static>(
    &self,
    f: F
) -> SignalHandlerId

pub fn connect_hide_expander_notify<F: Fn(&Self) + 'static>(
    &self,
    f: F
) -> SignalHandlerId

Available on crate feature v4_10 only.

pub fn connect_indent_for_depth_notify<F: Fn(&Self) + 'static>(
    &self,
    f: F
) -> SignalHandlerId

Available on crate feature v4_10 only.

pub fn connect_indent_for_icon_notify<F: Fn(&Self) + 'static>(
    &self,
    f: F
) -> SignalHandlerId

Available on crate feature v4_6 only.

pub fn connect_item_notify<F: Fn(&Self) + 'static>(
    &self,
    f: F
) -> SignalHandlerId

pub fn connect_list_row_notify<F: Fn(&Self) + 'static>(
    &self,
    f: F
) -> SignalHandlerId

Trait Implementations

impl Clone for TreeExpander

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 TreeExpander

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

Formats the value using the given formatter.

impl Default for TreeExpander

fn default() -> Self

Returns the “default value” for a type.

impl Display for TreeExpander

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

Formats the value using the given formatter.

impl Hash for TreeExpander

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 Ord for TreeExpander

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

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere
    Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl ParentClassIs for TreeExpander

type Parent = Widget

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

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 TreeExpander

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 TreeExpander

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for TreeExpander

impl IsA<Accessible> for TreeExpander

impl IsA<Buildable> for TreeExpander

impl IsA<ConstraintTarget> for TreeExpander

impl IsA<Widget> for TreeExpander