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Description [src]

abstract class Gtk.Widget : GObject.InitiallyUnowned
  implements Gtk.Accessible, Gtk.Buildable, Gtk.ConstraintTarget {
  /* No available fields */
}

The base class for all widgets.

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

Minimum and natural size

In order to understand geometry management of widgets in GTK, it is helpful to understand the different terminology surrounding sizing of widgets.

The two primary terms are: minimum size and natural size.

As a general rule: the minimum size is the size required to display the minimum amount of content in a widget. A widget cannot be allocated less than the minimum size it requires.

The natural size is the amount of content that a widget prefers to display in normal conditions.

A widget may be allocated more than the natural size it prefers, or less, depending on the layout management of its parent container. What to do when the widget is allocated a different size than the one it prefers is entirely left to the widget implementation: some widgets decide to add extra room, other widgets may disclose additional content, other widgets may decide to hide content, or show a different layout entirely.

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:

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 GtkWidget subclass that supports height-for-width or width-for-height geometry management for itself or its child widgets, the Gtk.WidgetClass.get_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 GTK_SIZE_REQUEST_CONSTANT_SIZE, which means that the widget will only ever get -1 passed as the for_size value to its Gtk.WidgetClass.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 GtkSizeRequestMode chosen by the toplevel.

For example, when queried in the normal GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH mode:

First, the default minimum and natural width for each widget in the interface will be computed using gtk_widget_measure() with an orientation of GTK_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 gtk_widget_measure() with an orientation of GTK_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 gtk_window_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, GtkWidget 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 GtkSizeRequestModes even if the widget in question only trades sizes in a single orientation.

For instance, a GtkLabel that does height-for-width word wrapping will not expect to have Gtk.WidgetClass.measure with an orientation of GTK_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 GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH widget generally deals with width-for-height requests:

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 gtk_widget_measure() inside your own Gtk.WidgetClass.size_allocate implementation. These return a request adjusted by GtkSizeGroup, 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 gtk_widget_measure(); otherwise, you would not properly consider widget margins, GtkSizeGroup, 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 Gtk.WidgetClass.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 GTK_ALIGN_FILL, but the selected baseline can be found via gtk_widget_get_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 GtkWidget implementation of the GtkBuildable interface supports various custom elements to specify additional aspects of widgets that are not directly expressed as properties.

If the widget uses a GtkLayoutManager, GtkWidget 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>

GtkWidget 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>

GtkWidget 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

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

To create composite widgets with GtkBuilder XML, one must associate the interface description with the widget class at class initialization time using gtk_widget_class_set_template().

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

Unlike regular interface descriptions, gtk_widget_class_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 GtkBuilder 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 gtk_widget_class_set_template_from_resource() from the class initialization of your GtkWidget type:

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:

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:

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 gtk_widget_class_bind_template_child_full() (or one of its wrapper macros gtk_widget_class_bind_template_child() and gtk_widget_class_bind_template_child_private()) with that name, e.g.

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 gtk_widget_class_bind_template_callback_full() (or is wrapper macro gtk_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 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);
}

Hierarchy

Ancestors

GInitiallyUnowned
GObject

Descendants

Implements

Functions

gtk_widget_get_default_direction

Obtains the default reading direction.

gtk_widget_set_default_direction

Sets the default reading direction for widgets.

Instance methods

gtk_widget_action_set_enabled

Enables or disables an action installed with gtk_widget_class_install_action().

gtk_widget_activate

Activates the widget.

gtk_widget_activate_action

Activates an action for the widget.

gtk_widget_activate_action_variant

Activates an action for the widget.

gtk_widget_activate_default

Activates the default.activate action for the widget.

gtk_widget_add_controller

Adds an event controller to the widget.

gtk_widget_add_css_class

Adds a style class to the widget.

gtk_widget_add_mnemonic_label

Adds a widget to the list of mnemonic labels for this widget.

gtk_widget_add_tick_callback

Queues an animation frame update and adds a callback to be called before each frame.

gtk_widget_allocate

Assigns size, position, (optionally) a baseline and transform to a child widget.

gtk_widget_child_focus

Called by widgets as the user moves around the window using keyboard shortcuts.

gtk_widget_compute_bounds

Computes the bounds for widget in the coordinate space of target.

gtk_widget_compute_expand

Computes whether a parent widget should give this widget extra space when possible.

gtk_widget_compute_point

Translates the given point in widget‘s coordinates to coordinates in target’s coordinate system.

gtk_widget_compute_transform

Computes a matrix suitable to describe a transformation from widget‘s coordinate system into target‘s coordinate system.

gtk_widget_contains

Tests if a given point is contained in the widget.

gtk_widget_create_pango_context

Creates a new PangoContext that is configured for the widget.

gtk_widget_create_pango_layout

Creates a new PangoLayout that is configured for the widget.

gtk_widget_dispose_template

Clears the template children for the widget.

since: 4.8

gtk_drag_check_threshold

Checks to see if a drag movement has passed the GTK drag threshold.

gtk_widget_error_bell

Notifies the user about an input-related error on the widget.

gtk_widget_get_allocated_baseline

Returns the baseline that has currently been allocated to the widget.

deprecated: 4.12

gtk_widget_get_allocated_height

Returns the height that has currently been allocated to the widget.

deprecated: 4.12

gtk_widget_get_allocated_width

Returns the width that has currently been allocated to the widget.

deprecated: 4.12

gtk_widget_get_allocation

Retrieves the widget’s allocation.

deprecated: 4.12

gtk_widget_get_ancestor

Gets the first ancestor of the widget with type widget_type.

gtk_widget_get_baseline

Returns the baseline that has currently been allocated to the widget.

since: 4.12

gtk_widget_get_can_focus

Determines whether the input focus can enter the widget or any of its children.

gtk_widget_get_can_target

Queries whether the widget can be the target of pointer events.

gtk_widget_get_child_visible

Gets the value set with gtk_widget_set_child_visible().

gtk_widget_get_clipboard

Gets the clipboard object for the widget.

gtk_widget_get_color

Gets the current foreground color for the widget’s style.

since: 4.10

gtk_widget_get_css_classes

Returns the list of style classes applied to the widget.

gtk_widget_get_css_name

Returns the CSS name of the widget.

gtk_widget_get_cursor

Gets the cursor set on the widget.

gtk_widget_get_direction

Gets the reading direction for the widget.

gtk_widget_get_display

Get the display for the window that the widget belongs to.

gtk_widget_get_first_child

Returns the widget’s first child.

gtk_widget_get_focus_child

Returns the focus child of the widget.

gtk_widget_get_focus_on_click

Returns whether the widget should grab focus when it is clicked with the mouse.

gtk_widget_get_focusable

Determines whether the widget can own the input focus.

gtk_widget_get_font_map

Gets the font map of the widget.

gtk_widget_get_font_options

Returns the cairo_font_options_t of the widget.

deprecated: 4.16

gtk_widget_get_frame_clock

Obtains the frame clock for a widget.

gtk_widget_get_halign

Gets the horizontal alignment of the widget.

gtk_widget_get_has_tooltip

Returns the current value of the has-tooltip property.

gtk_widget_get_height

Returns the content height of the widget.

gtk_widget_get_hexpand

Gets whether the widget would like any available extra horizontal space.

gtk_widget_get_hexpand_set

Gets whether the hexpand flag has been explicitly set.

gtk_widget_get_last_child

Returns the widget’s last child.

gtk_widget_get_layout_manager

Retrieves the layout manager of the widget.

gtk_widget_get_limit_events

Gets the value of the GtkWidget:limit-events property.

since: 4.18

gtk_widget_get_mapped

Returns whether the widget is mapped.

gtk_widget_get_margin_bottom

Gets the bottom margin of the widget.

gtk_widget_get_margin_end

Gets the end margin of the widget.

gtk_widget_get_margin_start

Gets the start margin of the widget.

gtk_widget_get_margin_top

Gets the top margin of the widget.

gtk_widget_get_name

Retrieves the name of a widget.

gtk_widget_get_native

Returns the nearest GtkNative ancestor of the widget.

gtk_widget_get_next_sibling

Returns the widget’s next sibling.

gtk_widget_get_opacity

Fetches the requested opacity for the widget.

gtk_widget_get_overflow

Returns the widget’s overflow value.

gtk_widget_get_pango_context

Gets a PangoContext that is configured for the widget.

gtk_widget_get_parent

Returns the parent widget of the widget.

gtk_widget_get_preferred_size

Retrieves the minimum and natural size of a widget, taking into account the widget’s preference for height-for-width management.

gtk_widget_get_prev_sibling

Returns the widget’s previous sibling.

gtk_widget_get_primary_clipboard

Gets the primary clipboard of the widget.

gtk_widget_get_realized

Determines whether the widget is realized.

gtk_widget_get_receives_default

Determines whether the widget is always treated as the default widget within its toplevel when it has the focus, even if another widget is the default.

gtk_widget_get_request_mode

Gets whether the widget prefers a height-for-width layout or a width-for-height layout.

gtk_widget_get_root

Returns the GtkRoot widget of the widget.

gtk_widget_get_scale_factor

Retrieves the internal scale factor that maps from window coordinates to the actual device pixels.

gtk_widget_get_sensitive

Returns the widget’s sensitivity.

gtk_widget_get_settings

Gets the settings object holding the settings used for the widget.

gtk_widget_get_size

Returns the content width or height of the widget.

gtk_widget_get_size_request

Gets the size request that was explicitly set for the widget.

gtk_widget_get_state_flags

Returns the widget state as a flag set.

gtk_widget_get_style_context

Returns the style context associated to the widget.

deprecated: 4.10

gtk_widget_get_template_child

Fetches an object build from the template XML for widget_type in the widget.

gtk_widget_get_tooltip_markup

Gets the contents of the tooltip for the widget.

gtk_widget_get_tooltip_text

Gets the contents of the tooltip for the widget.

gtk_widget_get_valign

Gets the vertical alignment of the widget.

gtk_widget_get_vexpand

Gets whether the widget would like any available extra vertical space.

gtk_widget_get_vexpand_set

Gets whether the vexpand flag has been explicitly set.

gtk_widget_get_visible

Determines whether the widget is visible.

gtk_widget_get_width

Returns the content width of the widget.

gtk_widget_grab_focus

Causes widget to have the keyboard focus for the window that it belongs to.

gtk_widget_has_css_class

Returns whether a style class is currently applied to the widget.

gtk_widget_has_default

Determines whether the widget is the current default widget within its toplevel.

gtk_widget_has_focus

Determines if the widget has the global input focus.

gtk_widget_has_visible_focus

Determines if the widget should show a visible indication that it has the global input focus.

gtk_widget_hide

Reverses the effects of [method.Gtk.Widget.show].

deprecated: 4.10

gtk_widget_in_destruction

Returns whether the widget is currently being destroyed.

gtk_widget_init_template

Creates and initializes child widgets defined in templates.

gtk_widget_insert_action_group

Inserts an action group into the widget’s actions.

gtk_widget_insert_after

Sets the parent widget of the widget.

gtk_widget_insert_before

Sets the parent widget of the widget.

gtk_widget_is_ancestor

Determines whether the widget is a descendent of ancestor.

gtk_widget_is_drawable

Determines whether the widget can be drawn to.

gtk_widget_is_focus

Determines if the widget is the focus widget within its toplevel.

gtk_widget_is_sensitive

Returns the widget’s effective sensitivity.

gtk_widget_is_visible

Determines whether the widget and all its parents are marked as visible.

gtk_widget_keynav_failed

Emits the GtkWidget::keynav-failed signal on the widget.

gtk_widget_list_mnemonic_labels

Returns the widgets for which this widget is the target of a mnemonic.

gtk_widget_map

Causes a widget to be mapped if it isn’t already.

gtk_widget_measure

Measures widget in the orientation orientation and for the given for_size.

gtk_widget_mnemonic_activate

Emits the GtkWidget::mnemonic-activate signal.

gtk_widget_observe_children

Returns a list model to track the children of the widget.

gtk_widget_observe_controllers

Returns a list model to track the event controllers of the widget.

gtk_widget_pick

Finds the descendant of the widget closest to a point.

gtk_widget_queue_allocate

Flags the widget for a rerun of the Gtk.WidgetClass.size_allocate function.

gtk_widget_queue_draw

Schedules this widget to be redrawn.

gtk_widget_queue_resize

Flags a widget to have its size renegotiated.

gtk_widget_realize

Creates the GDK resources associated with a widget.

gtk_widget_remove_controller

Removes an event controller from the widget.

gtk_widget_remove_css_class

Removes a style from the widget.

gtk_widget_remove_mnemonic_label

Removes a widget from the list of mnemonic labels for this widget.

gtk_widget_remove_tick_callback

Removes a tick callback previously registered with gtk_widget_add_tick_callback().

gtk_widget_set_can_focus

Sets whether the input focus can enter the widget or any of its children.

gtk_widget_set_can_target

Sets whether the widget can be the target of pointer events.

gtk_widget_set_child_visible

Sets whether the widget should be mapped along with its parent.

gtk_widget_set_css_classes

Replaces the current style classes of the widget with classes.

gtk_widget_set_cursor

Sets the cursor to be shown when the pointer hovers over the widget.

gtk_widget_set_cursor_from_name

Sets the cursor to be shown when the pointer hovers over the widget.

gtk_widget_set_direction

Sets the reading direction on the widget.

gtk_widget_set_focus_child

Set the focus child of the widget.

gtk_widget_set_focus_on_click

Sets whether the widget should grab focus when it is clicked with the mouse.

gtk_widget_set_focusable

Sets whether the widget can own the input focus.

gtk_widget_set_font_map

Sets the font map to use for text rendering in the widget.

gtk_widget_set_font_options

Sets the cairo_font_options_t used for text rendering in the widget.

deprecated: 4.16

gtk_widget_set_halign

Sets the horizontal alignment of the widget.

gtk_widget_set_has_tooltip

Sets the has-tooltip property on the widget.

gtk_widget_set_hexpand

Sets whether the widget would like any available extra horizontal space.

gtk_widget_set_hexpand_set

Sets whether the hexpand flag will be used.

gtk_widget_set_layout_manager

Sets the layout manager to use for measuring and allocating children of the widget.

gtk_widget_set_limit_events

Sets whether the widget acts like a modal dialog, with respect to event delivery.

since: 4.18

gtk_widget_set_margin_bottom

Sets the bottom margin of the widget.

gtk_widget_set_margin_end

Sets the end margin of the widget.

gtk_widget_set_margin_start

Sets the start margin of the widget.

gtk_widget_set_margin_top

Sets the top margin of the widget.

gtk_widget_set_name

Sets a widgets name.

gtk_widget_set_opacity

Requests the widget to be rendered partially transparent.

gtk_widget_set_overflow

Sets how the widget treats content that is drawn outside the it’s content area.

gtk_widget_set_parent

Sets the parent widget of the widget.

gtk_widget_set_receives_default

Sets whether the widget will be treated as the default widget within its toplevel when it has the focus, even if another widget is the default.

gtk_widget_set_sensitive

Sets the sensitivity of the widget.

gtk_widget_set_size_request

Sets the minimum size of the widget.

gtk_widget_set_state_flags

Turns on flag values in the current widget state.

gtk_widget_set_tooltip_markup

Sets the contents of the tooltip for widget.

gtk_widget_set_tooltip_text

Sets the contents of the tooltip for the widget.

gtk_widget_set_valign

Sets the vertical alignment of the widget.

gtk_widget_set_vexpand

Sets whether the widget would like any available extra vertical space.

gtk_widget_set_vexpand_set

Sets whether the vexpand flag will be used.

gtk_widget_set_visible

Sets the visibility state of widget.

gtk_widget_should_layout

Returns whether the widget should contribute to the measuring and allocation of its parent.

gtk_widget_show

Flags a widget to be displayed.

deprecated: 4.10

gtk_widget_size_allocate

Allocates widget with a transformation that translates the origin to the position in allocation.

gtk_widget_snapshot_child

Snapshots a child of the widget.

gtk_widget_translate_coordinates

Translates coordinates relative to src_widget’s allocation to coordinates relative to dest_widget’s allocations.

deprecated: 4.12

gtk_widget_trigger_tooltip_query

Triggers a tooltip query on the display of the widget.

gtk_widget_unmap

Causes a widget to be unmapped if it’s currently mapped.

gtk_widget_unparent

Removes widget from its parent.

gtk_widget_unrealize

Causes a widget to be unrealized.

gtk_widget_unset_state_flags

Turns off flag values for the current widget state.

Methods inherited from GObject (43)

Please see GObject for a full list of methods.

Methods inherited from GtkAccessible (21)

gtk_accessible_announce

Requests the user’s screen reader to announce the given message.

since: 4.14

gtk_accessible_get_accessible_id

Retrieves the accessible identifier for the accessible object.

since: 4.22

gtk_accessible_get_accessible_parent

Retrieves the accessible parent for an accessible object.

since: 4.10

gtk_accessible_get_accessible_role

Retrieves the accessible role of an accessible object.

gtk_accessible_get_at_context

Retrieves the implementation for the given accessible object.

since: 4.10

gtk_accessible_get_bounds

Queries the coordinates and dimensions of this accessible.

since: 4.10

gtk_accessible_get_first_accessible_child

Retrieves the first accessible child of an accessible object.

since: 4.10

gtk_accessible_get_next_accessible_sibling

Retrieves the next accessible sibling of an accessible object.

since: 4.10

gtk_accessible_get_platform_state

Queries a platform state, such as focus.

since: 4.10

gtk_accessible_reset_property

Resets the accessible property to its default value.

gtk_accessible_reset_relation

Resets the accessible relation to its default value.

gtk_accessible_reset_state

Resets the accessible state to its default value.

gtk_accessible_set_accessible_parent

Sets the parent and sibling of an accessible object.

since: 4.10

gtk_accessible_update_next_accessible_sibling

Updates the next accessible sibling.

since: 4.10

gtk_accessible_update_platform_state

Informs ATs that the platform state has changed.

since: 4.18

gtk_accessible_update_property

Updates a list of accessible properties.

gtk_accessible_update_property_value

Updates an array of accessible properties.

gtk_accessible_update_relation

Updates a list of accessible relations.

gtk_accessible_update_relation_value

Updates an array of accessible relations.

gtk_accessible_update_state

Updates a list of accessible states.

gtk_accessible_update_state_value

Updates an array of accessible states.

Methods inherited from GtkBuildable (1)

gtk_buildable_get_buildable_id

Gets the ID of the buildable object.

Properties

Gtk.Widget:can-focus

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

Gtk.Widget:can-target

Whether the widget can receive pointer events.

Gtk.Widget:css-classes

A list of css classes applied to this widget.

Gtk.Widget:css-name

The name of this widget in the CSS tree.

Gtk.Widget:cursor

The cursor used by widget.

Gtk.Widget:focus-on-click

Whether the widget should grab focus when it is clicked with the mouse.

Gtk.Widget:focusable

Whether this widget itself will accept the input focus.

Gtk.Widget:halign

How to distribute horizontal space if widget gets extra space.

Gtk.Widget:has-default

Whether the widget is the default widget.

Gtk.Widget:has-focus

Whether the widget has the input focus.

Gtk.Widget:has-tooltip

Enables or disables the emission of the GtkWidget::query-tooltip signal on widget.

Gtk.Widget:height-request

Overrides for height request of the widget.

Gtk.Widget:hexpand

Whether to expand horizontally.

Gtk.Widget:hexpand-set

Whether to use the hexpand property.

Gtk.Widget:layout-manager

The GtkLayoutManager instance to use to compute the preferred size of the widget, and allocate its children.

Gtk.Widget:limit-events

Makes this widget act like a modal dialog, with respect to event delivery.

since: 4.18

Gtk.Widget:margin-bottom

Margin on bottom side of widget.

Gtk.Widget:margin-end

Margin on end of widget, horizontally.

Gtk.Widget:margin-start

Margin on start of widget, horizontally.

Gtk.Widget:margin-top

Margin on top side of widget.

Gtk.Widget:name

The name of the widget.

Gtk.Widget:opacity

The requested opacity of the widget.

Gtk.Widget:overflow

How content outside the widget’s content area is treated.

Gtk.Widget:parent

The parent widget of this widget.

Gtk.Widget:receives-default

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

Gtk.Widget:root

The GtkRoot widget of the widget tree containing this widget.

Gtk.Widget:scale-factor

The scale factor of the widget.

Gtk.Widget:sensitive

Whether the widget responds to input.

Gtk.Widget:tooltip-markup

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

Gtk.Widget:tooltip-text

Sets the text of tooltip to be the given string.

Gtk.Widget:valign

How to distribute vertical space if widget gets extra space.

Gtk.Widget:vexpand

Whether to expand vertically.

Gtk.Widget:vexpand-set

Whether to use the vexpand property.

Gtk.Widget:visible

Whether the widget is visible.

Gtk.Widget:width-request

Overrides for width request of the widget.

Properties inherited from GtkAccessible (1)

GtkAccessible:accessible-role

The accessible role of the given GtkAccessible implementation.

Signals

Gtk.Widget::destroy

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

Gtk.Widget::direction-changed

Emitted when the text direction of a widget changes.

Gtk.Widget::hide

Emitted when widget is hidden.

Gtk.Widget::keynav-failed

Emitted if keyboard navigation fails.

Gtk.Widget::map

Emitted when widget is going to be mapped.

Gtk.Widget::mnemonic-activate

Emitted when a widget is activated via a mnemonic.

Gtk.Widget::move-focus

Emitted when the focus is moved.

Gtk.Widget::query-tooltip

Emitted when the widget’s tooltip is about to be shown.

Gtk.Widget::realize

Emitted when widget is associated with a GdkSurface.

Gtk.Widget::show

Emitted when widget is shown.

Gtk.Widget::state-flags-changed

Emitted when the widget state changes.

Gtk.Widget::unmap

Emitted when widget is going to be unmapped.

Gtk.Widget::unrealize

Emitted when the GdkSurface associated with widget is destroyed.

Signals inherited from GObject (1)

GObject::notify

The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.

Class structure

struct GtkWidgetClass {
  GInitiallyUnownedClass parent_class;
  void (* show) (
    GtkWidget* widget
  );
  void (* hide) (
    GtkWidget* widget
  );
  void (* map) (
    GtkWidget* widget
  );
  void (* unmap) (
    GtkWidget* widget
  );
  void (* realize) (
    GtkWidget* widget
  );
  void (* unrealize) (
    GtkWidget* widget
  );
  void (* root) (
    GtkWidget* widget
  );
  void (* unroot) (
    GtkWidget* widget
  );
  void (* size_allocate) (
    GtkWidget* widget,
    int width,
    int height,
    int baseline
  );
  void (* state_flags_changed) (
    GtkWidget* widget,
    GtkStateFlags previous_state_flags
  );
  void (* direction_changed) (
    GtkWidget* widget,
    GtkTextDirection previous_direction
  );
  GtkSizeRequestMode (* get_request_mode) (
    GtkWidget* widget
  );
  void (* measure) (
    GtkWidget* widget,
    GtkOrientation orientation,
    int for_size,
    int* minimum,
    int* natural,
    int* minimum_baseline,
    int* natural_baseline
  );
  gboolean (* mnemonic_activate) (
    GtkWidget* widget,
    gboolean group_cycling
  );
  gboolean (* grab_focus) (
    GtkWidget* widget
  );
  gboolean (* focus) (
    GtkWidget* widget,
    GtkDirectionType direction
  );
  void (* set_focus_child) (
    GtkWidget* widget,
    GtkWidget* child
  );
  void (* move_focus) (
    GtkWidget* widget,
    GtkDirectionType direction
  );
  gboolean (* keynav_failed) (
    GtkWidget* widget,
    GtkDirectionType direction
  );
  gboolean (* query_tooltip) (
    GtkWidget* widget,
    int x,
    int y,
    gboolean keyboard_tooltip,
    GtkTooltip* tooltip
  );
  void (* compute_expand) (
    GtkWidget* widget,
    gboolean* hexpand_p,
    gboolean* vexpand_p
  );
  void (* css_changed) (
    GtkWidget* widget,
    GtkCssStyleChange* change
  );
  void (* system_setting_changed) (
    GtkWidget* widget,
    GtkSystemSetting settings
  );
  void (* snapshot) (
    GtkWidget* widget,
    GtkSnapshot* snapshot
  );
  gboolean (* contains) (
    GtkWidget* widget,
    double x,
    double y
  );
  
}

No description available.

Class members

parent_class: GInitiallyUnownedClass: The object class structure needs to be the first element in the widget class structure in order for the class mechanism to work correctly. This allows a GtkWidgetClass pointer to be cast to a GObjectClass pointer.
show: void (* show) ( GtkWidget* widget ): Signal emitted when widget is shown.
hide: void (* hide) ( GtkWidget* widget ): Signal emitted when widget is hidden.
map: void (* map) ( GtkWidget* widget ): Signal emitted when widget is going to be mapped, that is when the widget is visible (which is controlled with gtk_widget_set_visible()) and all its parents up to the toplevel widget are also visible.
unmap: void (* unmap) ( GtkWidget* widget ): Signal emitted when widget is going to be unmapped, which means that either it or any of its parents up to the toplevel widget have been set as hidden.
realize: void (* realize) ( GtkWidget* widget ): Signal emitted when widget is associated with a GdkSurface, which means that gtk_widget_realize() has been called or the widget has been mapped (that is, it is going to be drawn).
unrealize: void (* unrealize) ( GtkWidget* widget ): Signal emitted when the GdkSurface associated with widget is destroyed, which means that gtk_widget_unrealize() has been called or the widget has been unmapped (that is, it is going to be hidden).
root: void (* root) ( GtkWidget* widget ): Called when the widget gets added to a GtkRoot widget. Must chain up.
unroot: void (* unroot) ( GtkWidget* widget ): Called when the widget is about to be removed from its GtkRoot widget. Must chain up.
size_allocate: void (* size_allocate) ( GtkWidget* widget, int width, int height, int baseline ): Called to set the allocation, if the widget does not have a layout manager.
state_flags_changed: void (* state_flags_changed) ( GtkWidget* widget, GtkStateFlags previous_state_flags ): Signal emitted when the widget state changes, see gtk_widget_get_state_flags().
direction_changed: void (* direction_changed) ( GtkWidget* widget, GtkTextDirection previous_direction ): Signal emitted when the text direction of a widget changes.
get_request_mode: GtkSizeRequestMode (* get_request_mode) ( GtkWidget* widget ): Called to get the request mode, if the widget does not have a layout manager. This allows a widget to tell its parent container whether it prefers to be allocated in GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH or GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT mode. GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH means the widget prefers to have GtkWidgetClass.measure() called first to get the default width (passing a for_size of -1), then again to get the height for said default width. GTK_SIZE_REQUEST_CONSTANT_SIZE disables any height-for-width or width-for-height geometry management for said widget and is the default return. It’s important to note that any widget which trades height-for-width or width-for-height must respond properly to a for_size value >= -1 passed to GtkWidgetClass.measure, for both possible orientations.
measure: void (* measure) ( GtkWidget* widget, GtkOrientation orientation, int for_size, int* minimum, int* natural, int* minimum_baseline, int* natural_baseline ): Called to obtain the minimum and natural size of the widget, if the widget does not have a layout manager. Depending on the orientation parameter, the passed for_size can be interpreted as width or height. A widget will never be allocated less than its minimum size.
mnemonic_activate: gboolean (* mnemonic_activate) ( GtkWidget* widget, gboolean group_cycling ): Activates the widget if group_cycling is FALSE, and just grabs the focus if group_cycling is TRUE.
grab_focus: gboolean (* grab_focus) ( GtkWidget* widget ): Causes widget to have the keyboard focus for the GtkWindow it’s inside.
focus: gboolean (* focus) ( GtkWidget* widget, GtkDirectionType direction ): Vfunc for gtk_widget_child_focus().
set_focus_child: void (* set_focus_child) ( GtkWidget* widget, GtkWidget* child ): Sets the focused child of a widget. Must chain up.
move_focus: void (* move_focus) ( GtkWidget* widget, GtkDirectionType direction ): Signal emitted when a change of focus is requested.
keynav_failed: gboolean (* keynav_failed) ( GtkWidget* widget, GtkDirectionType direction ): Signal emitted if keyboard navigation fails.
query_tooltip: gboolean (* query_tooltip) ( GtkWidget* widget, int x, int y, gboolean keyboard_tooltip, GtkTooltip* tooltip ): Signal emitted when “has-tooltip” is TRUE and the hover timeout has expired with the cursor hovering “above” widget; or emitted when widget got focus in keyboard mode.
compute_expand: void (* compute_expand) ( GtkWidget* widget, gboolean* hexpand_p, gboolean* vexpand_p ): Computes whether a container should give this widget extra space when possible.
css_changed: void (* css_changed) ( GtkWidget* widget, GtkCssStyleChange* change ): Vfunc called when the CSS used by widget was changed. Widgets should then discard their caches that depend on CSS and queue resizes or redraws accordingly. The default implementation will take care of this for all the default CSS properties, so implementations must chain up.
system_setting_changed: void (* system_setting_changed) ( GtkWidget* widget, GtkSystemSetting settings ): Emitted when a system setting was changed. Must chain up.
snapshot: void (* snapshot) ( GtkWidget* widget, GtkSnapshot* snapshot ): Vfunc called when a new snapshot of the widget has to be taken.
contains: gboolean (* contains) ( GtkWidget* widget, double x, double y ): Vfunc for gtk_widget_contains().

Virtual methods

Gtk.WidgetClass.compute_expand

Computes whether a container should give this widget extra space when possible.

Gtk.WidgetClass.contains

Tests if a given point is contained in the widget.

Gtk.WidgetClass.css_changed

Vfunc called when the CSS used by widget was changed. Widgets should then discard their caches that depend on CSS and queue resizes or redraws accordingly. The default implementation will take care of this for all the default CSS properties, so implementations must chain up.

Gtk.WidgetClass.direction_changed

Signal emitted when the text direction of a widget changes.

Gtk.WidgetClass.focus

Vfunc for gtk_widget_child_focus().

Gtk.WidgetClass.get_request_mode

Gets whether the widget prefers a height-for-width layout or a width-for-height layout.

Gtk.WidgetClass.grab_focus

Causes widget to have the keyboard focus for the window that it belongs to.

Gtk.WidgetClass.hide

Reverses the effects of [method.Gtk.Widget.show].

deprecated: 4.10

Gtk.WidgetClass.keynav_failed

Emits the GtkWidget::keynav-failed signal on the widget.

Gtk.WidgetClass.map

Causes a widget to be mapped if it isn’t already.

Gtk.WidgetClass.measure

Measures widget in the orientation orientation and for the given for_size.

Gtk.WidgetClass.mnemonic_activate

Emits the GtkWidget::mnemonic-activate signal.

Gtk.WidgetClass.move_focus

Signal emitted when a change of focus is requested.

Gtk.WidgetClass.query_tooltip

Signal emitted when “has-tooltip” is TRUE and the hover timeout has expired with the cursor hovering “above” widget; or emitted when widget got focus in keyboard mode.