Struct Widget

pub struct Widget { /* private fields */ }

The base class for all widgets.

It manages the widget lifecycle, layout, states and style.

Height-for-width Geometry Management

GTK uses a height-for-width (and width-for-height) geometry management system. Height-for-width means that a widget can change how much vertical space it needs, depending on the amount of horizontal space that it is given (and similar for width-for-height). The most common example is a label that reflows to fill up the available width, wraps to fewer lines, and therefore needs less height.

Height-for-width geometry management is implemented in GTK by way of two virtual methods:

• WidgetImpl::request_mode()
• WidgetImpl::measure()

There are some important things to keep in mind when implementing height-for-width and when using it in widget implementations.

If you implement a direct Widget subclass that supports height-for-width or width-for-height geometry management for itself or its child widgets, the WidgetImpl::request_mode() virtual function must be implemented as well and return the widget’s preferred request mode. The default implementation of this virtual function returns SizeRequestMode::ConstantSize, which means that the widget will only ever get -1 passed as the for_size value to its WidgetImpl::measure() implementation.

The geometry management system will query a widget hierarchy in only one orientation at a time. When widgets are initially queried for their minimum sizes it is generally done in two initial passes in the SizeRequestMode chosen by the toplevel.

For example, when queried in the normal SizeRequestMode::HeightForWidth mode:

First, the default minimum and natural width for each widget in the interface will be computed using WidgetExt::measure() with an orientation of Orientation::Horizontal and a for_size of -1. Because the preferred widths for each widget depend on the preferred widths of their children, this information propagates up the hierarchy, and finally a minimum and natural width is determined for the entire toplevel. Next, the toplevel will use the minimum width to query for the minimum height contextual to that width using WidgetExt::measure() with an orientation of Orientation::Vertical and a for_size of the just computed width. This will also be a highly recursive operation. The minimum height for the minimum width is normally used to set the minimum size constraint on the toplevel.

After the toplevel window has initially requested its size in both dimensions it can go on to allocate itself a reasonable size (or a size previously specified with GtkWindowExt::set_default_size()). During the recursive allocation process it’s important to note that request cycles will be recursively executed while widgets allocate their children. Each widget, once allocated a size, will go on to first share the space in one orientation among its children and then request each child’s height for its target allocated width or its width for allocated height, depending. In this way a widget will typically be requested its size a number of times before actually being allocated a size. The size a widget is finally allocated can of course differ from the size it has requested. For this reason, Widget caches a small number of results to avoid re-querying for the same sizes in one allocation cycle.

If a widget does move content around to intelligently use up the allocated size then it must support the request in both SizeRequestModes even if the widget in question only trades sizes in a single orientation.

For instance, a Label that does height-for-width word wrapping will not expect to have WidgetImpl::measure() with an orientation of Orientation::Vertical called because that call is specific to a width-for-height request. In this case the label must return the height required for its own minimum possible width. By following this rule any widget that handles height-for-width or width-for-height requests will always be allocated at least enough space to fit its own content.

Here are some examples of how a SizeRequestMode::HeightForWidth widget generally deals with width-for-height requests:

⚠️ The following code is in c ⚠️

static void
foo_widget_measure (GtkWidget      *widget,
                    GtkOrientation  orientation,
                    int             for_size,
                    int            *minimum_size,
                    int            *natural_size,
                    int            *minimum_baseline,
                    int            *natural_baseline)
{
  if (orientation == GTK_ORIENTATION_HORIZONTAL)
    {
      // Calculate minimum and natural width
    }
  else // VERTICAL
    {
      if (i_am_in_height_for_width_mode)
        {
          int min_width, dummy;

          // First, get the minimum width of our widget
          GTK_WIDGET_GET_CLASS (widget)->measure (widget, GTK_ORIENTATION_HORIZONTAL, -1,
                                                  &min_width, &dummy, &dummy, &dummy);

          // Now use the minimum width to retrieve the minimum and natural height to display
          // that width.
          GTK_WIDGET_GET_CLASS (widget)->measure (widget, GTK_ORIENTATION_VERTICAL, min_width,
                                                  minimum_size, natural_size, &dummy, &dummy);
        }
      else
        {
          // ... some widgets do both.
        }
    }
}

Often a widget needs to get its own request during size request or allocation. For example, when computing height it may need to also compute width. Or when deciding how to use an allocation, the widget may need to know its natural size. In these cases, the widget should be careful to call its virtual methods directly, like in the code example above.

It will not work to use the wrapper function WidgetExt::measure() inside your own WidgetImpl::size_allocate() implementation. These return a request adjusted by SizeGroup, the widget’s align and expand flags, as well as its CSS style.

If a widget used the wrappers inside its virtual method implementations, then the adjustments (such as widget margins) would be applied twice. GTK therefore does not allow this and will warn if you try to do it.

Of course if you are getting the size request for another widget, such as a child widget, you must use WidgetExt::measure(); otherwise, you would not properly consider widget margins, SizeGroup, and so forth.

GTK also supports baseline vertical alignment of widgets. This means that widgets are positioned such that the typographical baseline of widgets in the same row are aligned. This happens if a widget supports baselines, has a vertical alignment using baselines, and is inside a widget that supports baselines and has a natural “row” that it aligns to the baseline, or a baseline assigned to it by the grandparent.

Baseline alignment support for a widget is also done by the WidgetImpl::measure() virtual function. It allows you to report both a minimum and natural size.

If a widget ends up baseline aligned it will be allocated all the space in the parent as if it was Align::Fill, but the selected baseline can be found via WidgetExt::baseline(). If the baseline has a value other than -1 you need to align the widget such that the baseline appears at the position.

GtkWidget as GtkBuildable

The Widget implementation of the Buildable interface supports various custom elements to specify additional aspects of widgets that are not directly expressed as properties.

If the widget uses a LayoutManager, Widget supports a custom <layout> element, used to define layout properties:

<object class="GtkGrid" id="my_grid">
  <child>
    <object class="GtkLabel" id="label1">
      <property name="label">Description</property>
      <layout>
        <property name="column">0</property>
        <property name="row">0</property>
        <property name="row-span">1</property>
        <property name="column-span">1</property>
      </layout>
    </object>
  </child>
  <child>
    <object class="GtkEntry" id="description_entry">
      <layout>
        <property name="column">1</property>
        <property name="row">0</property>
        <property name="row-span">1</property>
        <property name="column-span">1</property>
      </layout>
    </object>
  </child>
</object>

Widget allows style information such as style classes to be associated with widgets, using the custom <style> element:

<object class="GtkButton" id="button1">
  <style>
    <class name="my-special-button-class"/>
    <class name="dark-button"/>
  </style>
</object>

Widget allows defining accessibility information, such as properties, relations, and states, using the custom <accessibility> element:

<object class="GtkButton" id="button1">
  <accessibility>
    <property name="label">Download</property>
    <relation name="labelled-by">label1</relation>
  </accessibility>
</object>

Building composite widgets from template XML

GtkWidget exposes some facilities to automate the procedure of creating composite widgets using “templates”.

To create composite widgets with Builder XML, one must associate the interface description with the widget class at class initialization time using WidgetClassExt::set_template().

The interface description semantics expected in composite template descriptions is slightly different from regular Builder XML.

Unlike regular interface descriptions, WidgetClassExt::set_template() will expect a <template> tag as a direct child of the toplevel <interface> tag. The <template> tag must specify the “class” attribute which must be the type name of the widget. Optionally, the “parent” attribute may be specified to specify the direct parent type of the widget type; this is ignored by Builder but can be used by UI design tools to introspect what kind of properties and internal children exist for a given type when the actual type does not exist.

The XML which is contained inside the <template> tag behaves as if it were added to the <object> tag defining the widget itself. You may set properties on a widget by inserting <property> tags into the <template> tag, and also add <child> tags to add children and extend a widget in the normal way you would with <object> tags.

Additionally, <object> tags can also be added before and after the initial <template> tag in the normal way, allowing one to define auxiliary objects which might be referenced by other widgets declared as children of the <template> tag.

Since, unlike the <object> tag, the <template> tag does not contain an “id” attribute, if you need to refer to the instance of the object itself that the template will create, simply refer to the template class name in an applicable element content.

Here is an example of a template definition, which includes an example of this in the <signal> tag:

<interface>
  <template class="FooWidget" parent="GtkBox">
    <property name="orientation">horizontal</property>
    <property name="spacing">4</property>
    <child>
      <object class="GtkButton" id="hello_button">
        <property name="label">Hello World</property>
        <signal name="clicked" handler="hello_button_clicked" object="FooWidget" swapped="yes"/>
      </object>
    </child>
    <child>
      <object class="GtkButton" id="goodbye_button">
        <property name="label">Goodbye World</property>
      </object>
    </child>
  </template>
</interface>

Typically, you’ll place the template fragment into a file that is bundled with your project, using GResource. In order to load the template, you need to call WidgetClassExt::set_template_from_resource() from the class initialization of your Widget type:

⚠️ The following code is in c ⚠️

static void
foo_widget_class_init (FooWidgetClass *klass)
{
  // ...

  gtk_widget_class_set_template_from_resource (GTK_WIDGET_CLASS (klass),
                                               "/com/example/ui/foowidget.ui");
}

You will also need to call Gtk::Widget::init_template() from the instance initialization function:

⚠️ The following code is in c ⚠️

static void
foo_widget_init (FooWidget *self)
{
  gtk_widget_init_template (GTK_WIDGET (self));

  // Initialize the rest of the widget...
}

as well as calling Gtk::Widget::dispose_template() from the dispose function:

⚠️ The following code is in c ⚠️

static void
foo_widget_dispose (GObject *gobject)
{
  FooWidget *self = FOO_WIDGET (gobject);

  // Dispose objects for which you have a reference...

  // Clear the template children for this widget type
  gtk_widget_dispose_template (GTK_WIDGET (self), FOO_TYPE_WIDGET);

  G_OBJECT_CLASS (foo_widget_parent_class)->dispose (gobject);
}

You can access widgets defined in the template using the Gtk::Widget::get_template_child() function, but you will typically declare a pointer in the instance private data structure of your type using the same name as the widget in the template definition, and call [WidgetClassExt::bind_template_child_full()][crate::subclass::prelude::WidgetClassExt::bind_template_child_full()] (or one of its wrapper macros widget_class_bind_template_child() and widget_class_bind_template_child_private()) with that name, e.g.

⚠️ The following code is in c ⚠️

typedef struct {
  GtkWidget *hello_button;
  GtkWidget *goodbye_button;
} FooWidgetPrivate;

G_DEFINE_TYPE_WITH_PRIVATE (FooWidget, foo_widget, GTK_TYPE_BOX)

static void
foo_widget_dispose (GObject *gobject)
{
  gtk_widget_dispose_template (GTK_WIDGET (gobject), FOO_TYPE_WIDGET);

  G_OBJECT_CLASS (foo_widget_parent_class)->dispose (gobject);
}

static void
foo_widget_class_init (FooWidgetClass *klass)
{
  // ...
  G_OBJECT_CLASS (klass)->dispose = foo_widget_dispose;

  gtk_widget_class_set_template_from_resource (GTK_WIDGET_CLASS (klass),
                                               "/com/example/ui/foowidget.ui");
  gtk_widget_class_bind_template_child_private (GTK_WIDGET_CLASS (klass),
                                                FooWidget, hello_button);
  gtk_widget_class_bind_template_child_private (GTK_WIDGET_CLASS (klass),
                                                FooWidget, goodbye_button);
}

static void
foo_widget_init (FooWidget *widget)
{
  gtk_widget_init_template (GTK_WIDGET (widget));
}

You can also use [WidgetClassExt::bind_template_callback_full()][crate::subclass::prelude::WidgetClassExt::bind_template_callback_full()] (or is wrapper macro widget_class_bind_template_callback()) to connect a signal callback defined in the template with a function visible in the scope of the class, e.g.

⚠️ The following code is in c ⚠️

// the signal handler has the instance and user data swapped
// because of the swapped="yes" attribute in the template XML
static void
hello_button_clicked (FooWidget *self,
                      GtkButton *button)
{
  g_print ("Hello, world!\n");
}

static void
foo_widget_class_init (FooWidgetClass *klass)
{
  // ...
  gtk_widget_class_set_template_from_resource (GTK_WIDGET_CLASS (klass),
                                               "/com/example/ui/foowidget.ui");
  gtk_widget_class_bind_template_callback (GTK_WIDGET_CLASS (klass), hello_button_clicked);
}

This is an Abstract Base Class, you cannot instantiate it.

Properties

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 true value 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

Overrides 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

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().

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 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 | 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 NULL: 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 NULL: 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

Overrides 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

Signals

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.

The ::move-focus signal is a keybinding signal.

The default bindings for this signal are Tab to move forward, and Shift+Tab to move backward.

Action

query-tooltip

Emitted when the widget’s 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).

Implements

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

GLib type: GObject with reference counted clone semantics.

Implementations

impl Widget

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

pub fn default_direction() -> TextDirection

Obtains the default reading direction.

See set_default_direction().

Returns

the current default direction

pub fn set_default_direction(dir: TextDirection)

Sets the default reading direction for widgets.

See WidgetExt::set_direction().

dir

the new default direction, either [enum@Gtk.TextDirection.ltr] or [enum@Gtk.TextDirection.rtl]

Trait Implementations

impl Clone for Widget

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 Widget

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

Formats the value using the given formatter.

impl Display for Widget

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

Formats the value using the given formatter.

impl HasParamSpec for Widget

type ParamSpec = ParamSpecObject

type SetValue = Widget

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

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

fn param_spec_builder() -> Self::BuilderFn

impl Hash for Widget

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<T: WidgetImpl> IsSubclassable<T> for Widget

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 Widget

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 Widget

type Parent = Object

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

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 Widget

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 Widget

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for Widget

impl IsA<Accessible> for Widget

impl IsA<Buildable> for Widget

impl IsA<ConstraintTarget> for Widget

impl IsA<Widget> for AboutDialog

impl IsA<Widget> for ActionBar

impl IsA<Widget> for Actionable

impl IsA<Widget> for AppChooser

impl IsA<Widget> for AppChooserButton

impl IsA<Widget> for AppChooserDialog

impl IsA<Widget> for AppChooserWidget

impl IsA<Widget> for ApplicationWindow

impl IsA<Widget> for AspectFrame

impl IsA<Widget> for Assistant

impl IsA<Widget> for Box

impl IsA<Widget> for Button

impl IsA<Widget> for Calendar

impl IsA<Widget> for CellEditable

impl IsA<Widget> for CellView

impl IsA<Widget> for CenterBox

impl IsA<Widget> for CheckButton

impl IsA<Widget> for ColorButton

impl IsA<Widget> for ColorChooserDialog

impl IsA<Widget> for ColorChooserWidget

impl IsA<Widget> for ColorDialogButton

Available on crate feature v4_10 only.

impl IsA<Widget> for ColumnView

impl IsA<Widget> for ComboBox

impl IsA<Widget> for ComboBoxText

impl IsA<Widget> for Dialog

impl IsA<Widget> for DragIcon

impl IsA<Widget> for DrawingArea

impl IsA<Widget> for DropDown

impl IsA<Widget> for Editable

impl IsA<Widget> for EditableLabel

impl IsA<Widget> for EmojiChooser

impl IsA<Widget> for Entry

impl IsA<Widget> for Expander

impl IsA<Widget> for FileChooserDialog

impl IsA<Widget> for FileChooserWidget

impl IsA<Widget> for Fixed

impl IsA<Widget> for FlowBox

impl IsA<Widget> for FlowBoxChild

impl IsA<Widget> for FontButton

impl IsA<Widget> for FontChooserDialog

impl IsA<Widget> for FontChooserWidget

impl IsA<Widget> for FontDialogButton

Available on crate feature v4_10 only.

impl IsA<Widget> for Frame

impl IsA<Widget> for GLArea

impl IsA<Widget> for GraphicsOffload

Available on crate feature v4_14 only.

impl IsA<Widget> for Grid

impl IsA<Widget> for GridView

impl IsA<Widget> for HeaderBar

impl IsA<Widget> for IconView

impl IsA<Widget> for Image

impl IsA<Widget> for InfoBar

impl IsA<Widget> for Inscription

Available on crate feature v4_8 only.

impl IsA<Widget> for Label

impl IsA<Widget> for LevelBar

impl IsA<Widget> for LinkButton

impl IsA<Widget> for ListBase

impl IsA<Widget> for ListBox

impl IsA<Widget> for ListBoxRow

impl IsA<Widget> for ListView

impl IsA<Widget> for LockButton

impl IsA<Widget> for MediaControls

impl IsA<Widget> for MenuButton

impl IsA<Widget> for MessageDialog

impl IsA<Widget> for Native

impl IsA<Widget> for Notebook

impl IsA<Widget> for Overlay

impl IsA<Widget> for PageSetupUnixDialog

Available on Linux only.

impl IsA<Widget> for Paned

impl IsA<Widget> for PasswordEntry

impl IsA<Widget> for Picture

impl IsA<Widget> for Popover

impl IsA<Widget> for PopoverMenu

impl IsA<Widget> for PopoverMenuBar

impl IsA<Widget> for PrintUnixDialog

Available on Linux only.

impl IsA<Widget> for ProgressBar

impl IsA<Widget> for Range

impl IsA<Widget> for Revealer

impl IsA<Widget> for Root

impl IsA<Widget> for Scale

impl IsA<Widget> for ScaleButton

impl IsA<Widget> for Scrollbar

impl IsA<Widget> for ScrolledWindow

impl IsA<Widget> for SearchBar

impl IsA<Widget> for SearchEntry

impl IsA<Widget> for Separator

impl IsA<Widget> for ShortcutLabel

impl IsA<Widget> for ShortcutsGroup

impl IsA<Widget> for ShortcutsSection

impl IsA<Widget> for ShortcutsShortcut

impl IsA<Widget> for ShortcutsWindow

impl IsA<Widget> for SpinButton

impl IsA<Widget> for Spinner

impl IsA<Widget> for Stack

impl IsA<Widget> for StackSidebar

impl IsA<Widget> for StackSwitcher

impl IsA<Widget> for Statusbar

impl IsA<Widget> for Switch

impl IsA<Widget> for Text

impl IsA<Widget> for TextView

impl IsA<Widget> for ToggleButton

impl IsA<Widget> for TreeExpander

impl IsA<Widget> for TreeView

impl IsA<Widget> for Video

impl IsA<Widget> for Viewport

impl IsA<Widget> for VolumeButton

impl IsA<Widget> for Window

impl IsA<Widget> for WindowControls

impl IsA<Widget> for WindowHandle