Class Toplevel

If the display of surface does not support per-surface beeps, emits a short beep on the display just as [methodGdk.Display.beep].

Whenever the source_property is changed the target_property is updated using the same value. For instance:

  g_object_bind_property (action, "active", widget, "sensitive", 0);

Will result in the "sensitive" property of the widget #GObject instance to be updated with the same value of the "active" property of the action #GObject instance.

If flags contains %G_BINDING_BIDIRECTIONAL then the binding will be mutual: if target_property on target changes then the source_property on source will be updated as well.

The binding will automatically be removed when either the source or the target instances are finalized. To remove the binding without affecting the source and the target you can just call g_object_unref() on the returned #GBinding instance.

Removing the binding by calling g_object_unref() on it must only be done if the binding, source and target are only used from a single thread and it is clear that both source and target outlive the binding. Especially it is not safe to rely on this if the binding, source or target can be finalized from different threads. Keep another reference to the binding and use g_binding_unbind() instead to be on the safe side.

A #GObject can have multiple bindings.

This function is the language bindings friendly version of g_object_bind_property_full(), using #GClosures instead of function pointers.

The context is disconnected from any particular surface or surface. If the creation of the GdkGLContext failed, error will be set. Before using the returned GdkGLContext, you will need to call [methodGdk.GLContext.make_current] or [methodGdk.GLContext.realize].

For example the new surface will have the same fallback resolution and font options as surface. Generally, the new surface will also use the same backend as surface, unless that is not possible for some reason. The type of the returned surface may be examined with cairo_surface_get_type().

Initially the surface contents are all 0 (transparent if contents have transparency, black otherwise.)

This function always returns a valid pointer, but it will return a pointer to a “nil” surface if other is already in an error state or any other error occurs.

If the creation of the GdkVulkanContext failed, error will be set.

The window system resources for all children of surface are also destroyed, but the children’s reference counts are not decremented.

Note that a surface will not be destroyed automatically when its reference count reaches zero. You must call this function yourself before that happens.

This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.

If the return value is %NULL then there is no custom cursor set on the surface, and it is using the cursor for its parent surface.

Use [methodGdk.Surface.set_cursor] to unset the cursor of the surface.

If the return value is %NULL then there is no custom cursor set on the specified surface, and it is using the cursor for its parent surface.

Use [methodGdk.Surface.set_cursor] to unset the cursor of the surface.

The position is given in coordinates relative to the upper left corner of surface.

The frame clock for a surface never changes unless the surface is reparented to a new toplevel surface.

Surface size is reported in ”application pixels”, not ”device pixels” (see [methodGdk.Surface.get_scale_factor]).

A surface is mapped with [methodGdk.Toplevel.present] or [methodGdk.Popup.present].

The value can be:

• an empty #GValue initialized by %G_VALUE_INIT, which will be automatically initialized with the expected type of the property (since GLib 2.60)
• a #GValue initialized with the expected type of the property
• a #GValue initialized with a type to which the expected type of the property can be transformed

In general, a copy is made of the property contents and the caller is responsible for freeing the memory by calling g_value_unset().

Note that g_object_get_property() is really intended for language bindings, g_object_get() is much more convenient for C programming.

On traditional systems this is 1, but on very high density outputs this can be a higher value (often 2). A higher value means that drawing is automatically scaled up to a higher resolution, so any code doing drawing will automatically look nicer. However, if you are supplying pixel-based data the scale value can be used to determine whether to use a pixel resource with higher resolution data.

The scale of a surface may change during runtime.

Surface size is reported in ”application pixels”, not ”device pixels” (see [methodGdk.Surface.get_scale_factor]).

For toplevel surfaces, withdraws them, so they will no longer be known to the window manager; for all surfaces, unmaps them, so they won’t be displayed. Normally done automatically as part of [methodGtk.Widget.hide].

When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.

This function omits the property name lookup, hence it is faster than g_object_notify().

One way to avoid using g_object_notify() from within the class that registered the properties, and using g_object_notify_by_pspec() instead, is to store the GParamSpec used with g_object_class_install_property() inside a static array, e.g.:

  enum
  {
    PROP_0,
    PROP_FOO,
    PROP_LAST
  };

  static GParamSpec *properties[PROP_LAST];

  static void
  my_object_class_init (MyObjectClass *klass)
  {
    properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo",
                                             0, 100,
                                             50,
                                             G_PARAM_READWRITE);
    g_object_class_install_property (gobject_class,
                                     PROP_FOO,
                                     properties[PROP_FOO]);
  }

and then notify a change on the "foo" property with:

  g_object_notify_by_pspec (self, properties[PROP_FOO]);

This function is useful for implementations that track invalid regions on their own.

Since GLib 2.56, if GLIB_VERSION_MAX_ALLOWED is 2.56 or greater, the type of object will be propagated to the return type (using the GCC typeof() extension), so any casting the caller needs to do on the return type must be explicit.

In other words, if the object is floating, then this call "assumes ownership" of the floating reference, converting it to a normal reference by clearing the floating flag while leaving the reference count unchanged. If the object is not floating, then this call adds a new normal reference increasing the reference count by one.

Since GLib 2.56, the type of object will be propagated to the return type under the same conditions as for g_object_ref().

See [methodGdk.FrameClock.request_phase].

This function should only be called from object system implementations.

Passing %NULL for the cursor argument means that surface will use the cursor of its parent surface. Most surfaces should use this default. Note that cursor must be for the same display as surface.

Use [ctorGdk.Cursor.new_from_name] or [ctorGdk.Cursor.new_from_texture] to create the cursor. To make the cursor invisible, use %GDK_BLANK_CURSOR.

If the object already had an association with that name, the old association will be destroyed.

Internally, the key is converted to a #GQuark using g_quark_from_string(). This means a copy of key is kept permanently (even after object has been finalized) — so it is recommended to only use a small, bounded set of values for key in your program, to avoid the #GQuark storage growing unbounded.

Passing %NULL for the cursor argument means that surface will use the cursor of its parent surface. Most surfaces should use this default.

Use [ctorGdk.Cursor.new_from_name] or [ctorGdk.Cursor.new_from_texture] to create the cursor. To make the cursor invisible, use %GDK_BLANK_CURSOR.

Mouse events which happen while the pointer position corresponds to an unset bit in the mask will be passed on the surface below surface.

An input region is typically used with RGBA surfaces. The alpha channel of the surface defines which pixels are invisible and allows for nicely antialiased borders, and the input region controls where the surface is “clickable”.

Use [methodGdk.Display.supports_input_shapes] to find out if a particular backend supports input regions.

For optimisation purposes, compositing window managers may like to not draw obscured regions of surfaces, or turn off blending during for these regions. With RGB windows with no transparency, this is just the shape of the window, but with ARGB32 windows, the compositor does not know what regions of the window are transparent or not.

This function only works for toplevel surfaces.

GTK will update this property automatically if the surface background is opaque, as we know where the opaque regions are. If your surface background is not opaque, please update this property in your [vfuncGtk.Widget.css_changed] handler.

void
object_add_to_user_list (GObject     *object,
                         const gchar *new_string)
{
  // the quark, naming the object data
  GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
  // retrieve the old string list
  GList *list = g_object_steal_qdata (object, quark_string_list);

  // prepend new string
  list = g_list_prepend (list, g_strdup (new_string));
  // this changed 'list', so we need to set it again
  g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
}
static void
free_string_list (gpointer data)
{
  GList *node, *list = data;

  for (node = list; node; node = node->next)
    g_free (node->data);
  g_list_free (list);
}

Using g_object_get_qdata() in the above example, instead of g_object_steal_qdata() would have left the destroy function set, and thus the partial string list would have been freed upon g_object_set_qdata_full().

Duplicate notifications for each property are squashed so that at most one #GObject::notify signal is emitted for each property, in the reverse order in which they have been queued.

It is an error to call this function when the freeze count is zero.

Note that this only works if to and from are popups or transient-for to the same toplevel (directly or indirectly).

If the pointer to the #GObject may be reused in future (for example, if it is an instance variable of another object), it is recommended to clear the pointer to %NULL rather than retain a dangling pointer to a potentially invalid #GObject instance. Use g_clear_object() for this.

When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.