Struct TreeExpander 

pub struct TreeExpander { /* private fields */ }

[`TreeExpander`][crate::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

Until GTK 4.10, [`TreeExpander`][crate::TreeExpander] used the [enum@Gtk.AccessibleRole.group] role.

Since GTK 4.12, [`TreeExpander`][crate::TreeExpander] uses the [enum@Gtk.AccessibleRole.button] role.
Toggling it will change the `GTK_ACCESSIBLE_STATE_EXPANDED` state.

## Properties


#### `child`
 The child widget with the actual contents.

Readable | Writable


#### `hide-expander`
 Whether the expander icon should be hidden in a GtkTreeListRow.
Note that this property simply hides the icon.  The actions and keybinding
(i.e. collapse and expand) are not affected by this property.

A common use for this property would be to bind to the number of children in a
GtkTreeListRow's model in order to hide the expander when a row has no children.

Readable | Writable


#### `indent-for-depth`
 TreeExpander indents the child according to its depth.

Readable | Writable


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

Readable | Writable


#### `item`
 The item held by this expander's row.

Readable


#### `list-row`
 The list row to track for expander state.

Readable | Writable
<details><summary><h4>Widget</h4></summary>


#### `can-focus`
 Whether the widget or any of its descendents can accept
the input focus.

This property is meant to be set by widget implementations,
typically in their instance init function.

Readable | Writable


#### `can-target`
 Whether the widget can receive pointer events.

Readable | Writable


#### `css-classes`
 A list of css classes applied to this widget.

Readable | Writable


#### `css-name`
 The name of this widget in the CSS tree.

This property is meant to be set by widget implementations,
typically in their instance init function.

Readable | Writable | Construct Only


#### `cursor`
 The cursor used by @widget.

Readable | Writable


#### `focus-on-click`
 Whether the widget should grab focus when it is clicked with the mouse.

This property is only relevant for widgets that can take focus.

Readable | Writable


#### `focusable`
 Whether this widget itself will accept the input focus.

Readable | Writable


#### `halign`
 How to distribute horizontal space if widget gets extra space.

Readable | Writable


#### `has-default`
 Whether the widget is the default widget.

Readable


#### `has-focus`
 Whether the widget has the input focus.

Readable


#### `has-tooltip`
 Enables or disables the emission of the [`query-tooltip`][struct@crate::Widget#query-tooltip]
signal on @widget.

A true value indicates that @widget can have a tooltip, in this case
the widget will be queried using [`query-tooltip`][struct@crate::Widget#query-tooltip] to
determine whether it will provide a tooltip or not.

Readable | Writable


#### `height-request`
 Overrides for height request of the widget.

If this is -1, the natural request will be used.

Readable | Writable


#### `hexpand`
 Whether to expand horizontally.

Readable | Writable


#### `hexpand-set`
 Whether to use the `hexpand` property.

Readable | Writable


#### `layout-manager`
 The [`LayoutManager`][crate::LayoutManager] instance to use to compute
the preferred size of the widget, and allocate its children.

This property is meant to be set by widget implementations,
typically in their instance init function.

Readable | Writable


#### `limit-events`
 Makes this widget act like a modal dialog, with respect to
event delivery.

Global event controllers will not handle events with targets
inside the widget, unless they are set up to ignore propagation
limits. See [`EventControllerExt::set_propagation_limit()`][crate::prelude::EventControllerExt::set_propagation_limit()].

Readable | Writable


#### `margin-bottom`
 Margin on bottom side of widget.

This property adds margin outside of the widget's normal size
request, the margin will be added in addition to the size from
[`WidgetExt::set_size_request()`][crate::prelude::WidgetExt::set_size_request()] for example.

Readable | Writable


#### `margin-end`
 Margin on end of widget, horizontally.

This property supports left-to-right and right-to-left text
directions.

This property adds margin outside of the widget's normal size
request, the margin will be added in addition to the size from
[`WidgetExt::set_size_request()`][crate::prelude::WidgetExt::set_size_request()] for example.

Readable | Writable


#### `margin-start`
 Margin on start of widget, horizontally.

This property supports left-to-right and right-to-left text
directions.

This property adds margin outside of the widget's normal size
request, the margin will be added in addition to the size from
[`WidgetExt::set_size_request()`][crate::prelude::WidgetExt::set_size_request()] for example.

Readable | Writable


#### `margin-top`
 Margin on top side of widget.

This property adds margin outside of the widget's normal size
request, the margin will be added in addition to the size from
[`WidgetExt::set_size_request()`][crate::prelude::WidgetExt::set_size_request()] for example.

Readable | Writable


#### `name`
 The name of the widget.

Readable | Writable


#### `opacity`
 The requested opacity of the widget.

Readable | Writable


#### `overflow`
 How content outside the widget's content area is treated.

This property is meant to be set by widget implementations,
typically in their instance init function.

Readable | Writable


#### `parent`
 The parent widget of this widget.

Readable


#### `receives-default`
 Whether the widget will receive the default action when it is focused.

Readable | Writable


#### `root`
 The [`Root`][crate::Root] widget of the widget tree containing this widget.

This will be `NULL` if the widget is not contained in a root widget.

Readable


#### `scale-factor`
 The scale factor of the widget.

Readable


#### `sensitive`
 Whether the widget responds to input.

Readable | Writable


#### `tooltip-markup`
 Sets the text of tooltip to be the given string, which is marked up
with Pango markup.

Also see [`Tooltip::set_markup()`][crate::Tooltip::set_markup()].

This is a convenience property which will take care of getting the
tooltip shown if the given string is not `NULL`:
[`has-tooltip`][struct@crate::Widget#has-tooltip] will automatically be set to true
and there will be taken care of [`query-tooltip`][struct@crate::Widget#query-tooltip] in
the default signal handler.

Note that if both [`tooltip-text`][struct@crate::Widget#tooltip-text] and
[`tooltip-markup`][struct@crate::Widget#tooltip-markup] are set, the last one wins.

Readable | Writable


#### `tooltip-text`
 Sets the text of tooltip to be the given string.

Also see [`Tooltip::set_text()`][crate::Tooltip::set_text()].

This is a convenience property which will take care of getting the
tooltip shown if the given string is not `NULL`:
[`has-tooltip`][struct@crate::Widget#has-tooltip] will automatically be set to true
and there will be taken care of [`query-tooltip`][struct@crate::Widget#query-tooltip] in
the default signal handler.

Note that if both [`tooltip-text`][struct@crate::Widget#tooltip-text] and
[`tooltip-markup`][struct@crate::Widget#tooltip-markup] are set, the last one wins.

Readable | Writable


#### `valign`
 How to distribute vertical space if widget gets extra space.

Readable | Writable


#### `vexpand`
 Whether to expand vertically.

Readable | Writable


#### `vexpand-set`
 Whether to use the `vexpand` property.

Readable | Writable


#### `visible`
 Whether the widget is visible.

Readable | Writable


#### `width-request`
 Overrides for width request of the widget.

If this is -1, the natural request will be used.

Readable | Writable
</details>
<details><summary><h4>Accessible</h4></summary>


#### `accessible-role`
 The accessible role of the given [`Accessible`][crate::Accessible] implementation.

The accessible role cannot be changed once set.

Readable | Writable
</details>

# Implements

[`WidgetExt`][trait@crate::prelude::WidgetExt], [`trait@glib::ObjectExt`], [`AccessibleExt`][trait@crate::prelude::AccessibleExt], [`BuildableExt`][trait@crate::prelude::BuildableExt], [`ConstraintTargetExt`][trait@crate::prelude::ConstraintTargetExt], [`WidgetExtManual`][trait@crate::prelude::WidgetExtManual], [`AccessibleExtManual`][trait@crate::prelude::AccessibleExtManual]

GLib type: GObject with reference counted clone semantics.

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

Makes a clone of this shared reference.

This increments the strong reference count of the object. Dropping the object will decrement it again.

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 Eq for TreeExpander

impl HasParamSpec for TreeExpander

type ParamSpec = ParamSpecObject

type SetValue = TreeExpander

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

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

fn param_spec_builder() -> Self::BuilderFn

impl Hash for TreeExpander

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

where H: Hasher,

Hashes the memory address of this object.

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 IsA<Accessible> for TreeExpander

impl IsA<Buildable> for TreeExpander

impl IsA<ConstraintTarget> for TreeExpander

impl IsA<Widget> for TreeExpander

impl Ord for TreeExpander

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

Comparison for two GObjects.

Compares the memory addresses of the provided objects.

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,

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

Equality for two GObjects.

Two GObjects are equal if their memory addresses are equal.

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

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>

Partial comparison for two GObjects.

Compares the memory addresses of the provided objects.

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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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.