Struct gtk4::ComboBox

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

Use DropDown instead A ComboBox is a widget that allows the user to choose from a list of valid choices.

The ComboBox displays the selected choice; when activated, the ComboBox displays a popup which allows the user to make a new choice.

The ComboBox uses the model-view pattern; the list of valid choices is specified in the form of a tree model, and the display of the choices can be adapted to the data in the model by using cell renderers, as you would in a tree view. This is possible since ComboBox implements the CellLayout interface. The tree model holding the valid choices is not restricted to a flat list, it can be a real tree, and the popup will reflect the tree structure.

To allow the user to enter values not in the model, the has-entry property allows the ComboBox to contain a Entry. This entry can be accessed by calling ComboBoxExt::child() on the combo box.

For a simple list of textual choices, the model-view API of ComboBox can be a bit overwhelming. In this case, ComboBoxText offers a simple alternative. Both ComboBox and ComboBoxText can contain an entry.

CSS nodes

combobox
├── box.linked
│   ╰── button.combo
│       ╰── box
│           ├── cellview
│           ╰── arrow
╰── window.popup

A normal combobox contains a box with the .linked class, a button with the .combo class and inside those buttons, there are a cellview and an arrow.

combobox
├── box.linked
│   ├── entry.combo
│   ╰── button.combo
│       ╰── box
│           ╰── arrow
╰── window.popup

A ComboBox with an entry has a single CSS node with name combobox. It contains a box with the .linked class. That box contains an entry and a button, both with the .combo class added. The button also contains another node with name arrow.

Accessibility

ComboBox uses the AccessibleRole::ComboBox role.

Properties

active

The item which is currently active.

If the model is a non-flat treemodel, and the active item is not an immediate child of the root of the tree, this property has the value gtk_tree_path_get_indices (path)[0], where path is the TreePath of the active item.

Readable | Writeable

active-id

The value of the ID column of the active row.

Readable | Writeable

button-sensitivity

Whether the dropdown button is sensitive when the model is empty.

Readable | Writeable

child

The child widget.

Readable | Writeable

entry-text-column

The model column to associate with strings from the entry.

This is property only relevant if the combo was created with has-entry is true.

Readable | Writeable

has-entry

Whether the combo box has an entry.

Readable | Writeable | Construct Only

has-frame

The has-frame property controls whether a frame is drawn around the entry.

Readable | Writeable

id-column

The model column that provides string IDs for the values in the model, if != -1.

Readable | Writeable

model

The model from which the combo box takes its values.

Readable | Writeable

popup-fixed-width

Whether the popup’s width should be a fixed width matching the allocated width of the combo box.

Readable | Writeable

popup-shown

Whether the combo boxes dropdown is popped up.

Note that this property is mainly useful, because it allows you to connect to notify::popup-shown.

Readable

Widget

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 | Writeable

can-target

Whether the widget can receive pointer events.

Readable | Writeable

css-classes

A list of css classes applied to this widget.

Readable | Writeable

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 | Writeable | Construct Only

cursor

The cursor used by @widget.

Readable | Writeable

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 | Writeable

focusable

Whether this widget itself will accept the input focus.

Readable | Writeable

halign

How to distribute horizontal space if widget gets extra space.

Readable | Writeable

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 signal on @widget.

A value of true indicates that @widget can have a tooltip, in this case the widget will be queried using query-tooltip to determine whether it will provide a tooltip or not.

Readable | Writeable

height-request

Override for height request of the widget.

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

Readable | Writeable

hexpand

Whether to expand horizontally.

Readable | Writeable

hexpand-set

Whether to use the hexpand property.

Readable | Writeable

layout-manager

The 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 | Writeable

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() for example.

Readable | Writeable

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() for example.

Readable | Writeable

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() for example.

Readable | Writeable

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() for example.

Readable | Writeable

name

The name of the widget.

Readable | Writeable

opacity

The requested opacity of the widget.

Readable | Writeable

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 | Writeable

parent

The parent widget of this widget.

Readable

receives-default

Whether the widget will receive the default action when it is focused.

Readable | Writeable

root

The Root widget of the widget tree containing this widget.

This will be None 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 | Writeable

tooltip-markup

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

Also see Tooltip::set_markup().

This is a convenience property which will take care of getting the tooltip shown if the given string is not None: has-tooltip will automatically be set to true and there will be taken care of query-tooltip in the default signal handler.

Note that if both tooltip-text and tooltip-markup are set, the last one wins.

Readable | Writeable

tooltip-text

Sets the text of tooltip to be the given string.

Also see Tooltip::set_text().

This is a convenience property which will take care of getting the tooltip shown if the given string is not None: has-tooltip will automatically be set to true and there will be taken care of query-tooltip in the default signal handler.

Note that if both tooltip-text and tooltip-markup are set, the last one wins.

Readable | Writeable

valign

How to distribute vertical space if widget gets extra space.

Readable | Writeable

vexpand

Whether to expand vertically.

Readable | Writeable

vexpand-set

Whether to use the vexpand property.

Readable | Writeable

visible

Whether the widget is visible.

Readable | Writeable

width-request

Override for width request of the widget.

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

Readable | Writeable

Accessible

accessible-role

The accessible role of the given Accessible implementation.

The accessible role cannot be changed once set.

Readable | Writeable

CellEditable

editing-canceled

Indicates whether editing on the cell has been canceled.

Readable | Writeable

Signals

activate

Emitted to when the combo box is activated.

The ::activate signal on ComboBox is an action signal and emitting it causes the combo box to pop up its dropdown.

Action

changed

Emitted when the active item is changed.

The can be due to the user selecting a different item from the list, or due to a call to ComboBoxExt::set_active_iter(). It will also be emitted while typing into the entry of a combo box with an entry.

format-entry-text

Emitted to allow changing how the text in a combo box’s entry is displayed.

See has-entry.

Connect a signal handler which returns an allocated string representing @path. That string will then be used to set the text in the combo box’s entry. The default signal handler uses the text from the entry-text-column model column.

Here’s an example signal handler which fetches data from the model and displays it in the entry. ⚠️ The following code is in c ⚠️

static char *
format_entry_text_callback (GtkComboBox *combo,
                            const char *path,
                            gpointer     user_data)
{
  GtkTreeIter iter;
  GtkTreeModel model;
  double       value;

  model = gtk_combo_box_get_model (combo);

  gtk_tree_model_get_iter_from_string (model, &iter, path);
  gtk_tree_model_get (model, &iter,
                      THE_DOUBLE_VALUE_COLUMN, &value,
                      -1);

  return g_strdup_printf ("%g", value);
}

move-active

Emitted to move the active selection.

This is an keybinding signal.

Action

popdown

Emitted to popdown the combo box list.

This is an keybinding signal.

The default bindings for this signal are Alt+Up and Escape.

Action

popup

Emitted to popup the combo box list.

This is an keybinding signal.

The default binding for this signal is Alt+Down.

Action

Widget

destroy

Signals that all holders of a reference to the widget should release the reference that they hold.

May result in finalization of the widget if all references are released.

This signal is not suitable for saving widget state.

direction-changed

Emitted when the text direction of a widget changes.

hide

Emitted when @widget is hidden.

keynav-failed

Emitted if keyboard navigation fails.

See WidgetExt::keynav_failed() for details.

map

Emitted when @widget is going to be mapped.

A widget is mapped when the widget is visible (which is controlled with visible) and all its parents up to the toplevel widget are also visible.

The ::map signal can be used to determine whether a widget will be drawn, for instance it can resume an animation that was stopped during the emission of unmap.

mnemonic-activate

Emitted when a widget is activated via a mnemonic.

The default handler for this signal activates @widget if @group_cycling is false, or just makes @widget grab focus if @group_cycling is true.

move-focus

Emitted when the focus is moved.

Action

query-tooltip

Emitted when the widgets tooltip is about to be shown.

This happens when the has-tooltip property is true and the hover timeout has expired with the cursor hovering “above” @widget; or emitted when @widget got focus in keyboard mode.

Using the given coordinates, the signal handler should determine whether a tooltip should be shown for @widget. If this is the case true should be returned, false otherwise. Note that if @keyboard_mode is true, the values of @x and @y are undefined and should not be used.

The signal handler is free to manipulate @tooltip with the therefore destined function calls.

realize

Emitted when @widget is associated with a gdk::Surface.

This means that WidgetExt::realize() has been called or the widget has been mapped (that is, it is going to be drawn).

show

Emitted when @widget is shown.

state-flags-changed

Emitted when the widget state changes.

See WidgetExt::state_flags().

unmap

Emitted when @widget is going to be unmapped.

A widget is unmapped when either it or any of its parents up to the toplevel widget have been set as hidden.

As ::unmap indicates that a widget will not be shown any longer, it can be used to, for example, stop an animation on the widget.

unrealize

Emitted when the gdk::Surface associated with @widget is destroyed.

This means that WidgetExt::unrealize() has been called or the widget has been unmapped (that is, it is going to be hidden).

CellEditable

editing-done

This signal is a sign for the cell renderer to update its value from the @cell_editable.

Implementations of CellEditable are responsible for emitting this signal when they are done editing, e.g. Entry emits this signal when the user presses Enter. Typical things to do in a handler for ::editing-done are to capture the edited value, disconnect the @cell_editable from signals on the CellRenderer, etc.

gtk_cell_editable_editing_done() is a convenience method for emitting GtkCellEditable::editing-done.

remove-widget

This signal is meant to indicate that the cell is finished editing, and the @cell_editable widget is being removed and may subsequently be destroyed.

Implementations of CellEditable are responsible for emitting this signal when they are done editing. It must be emitted after the GtkCellEditable::editing-done signal, to give the cell renderer a chance to update the cell’s value before the widget is removed.

gtk_cell_editable_remove_widget() is a convenience method for emitting GtkCellEditable::remove-widget.

Implements

ComboBoxExt, WidgetExt, glib::ObjectExt, AccessibleExt, BuildableExt, ConstraintTargetExt, CellEditableExt, CellLayoutExt, ComboBoxExtManual, WidgetExtManual, AccessibleExtManual, CellLayoutExtManual

Implementations

impl ComboBox

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

pub fn new() -> ComboBox

Creates a new empty ComboBox.

Deprecated since 4.10

Use DropDown

Returns

A new ComboBox

pub fn with_entry() -> ComboBox

Creates a new empty ComboBox with an entry.

In order to use a combo box with entry, you need to tell it which column of the model contains the text for the entry by calling ComboBoxExt::set_entry_text_column().

Deprecated since 4.10

Use DropDown

Returns

A new ComboBox

pub fn with_model(model: &impl IsA<TreeModel>) -> ComboBox

Creates a new ComboBox with a model.

Deprecated since 4.10

Use DropDown

model

a TreeModel

Returns

A new ComboBox

pub fn with_model_and_entry(model: &impl IsA<TreeModel>) -> ComboBox

Creates a new empty ComboBox with an entry and a model.

See also with_entry().

Deprecated since 4.10

Use DropDown

model

A TreeModel

Returns

A new ComboBox

pub fn builder() -> ComboBoxBuilder

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

This method returns an instance of ComboBoxBuilder which can be used to create ComboBox objects.

Trait Implementations

impl Clone for ComboBox

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 ComboBox

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

Formats the value using the given formatter.

impl Default for ComboBox

fn default() -> Self

Returns the “default value” for a type.

impl Display for ComboBox

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

Formats the value using the given formatter.

impl HasParamSpec for ComboBox

type ParamSpec = ParamSpecObject

type SetValue = ComboBox

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

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

fn param_spec_builder() -> Self::BuilderFn

impl Hash for ComboBox

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: ComboBoxImpl> IsSubclassable<T> for ComboBox

fn class_init(class: &mut Class<Self>)

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

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

Instance specific initialization.

impl Ord for ComboBox

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 ComboBox

type Parent = Widget

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

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 ComboBox

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 ComboBox

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for ComboBox

impl IsA<Accessible> for ComboBox

impl IsA<Buildable> for ComboBox

impl IsA<CellEditable> for ComboBox

impl IsA<CellLayout> for ComboBox

impl IsA<ComboBox> for ComboBoxText

impl IsA<ConstraintTarget> for ComboBox

impl IsA<Widget> for ComboBox