The possible actions for this drop
The GdkDevice
performing the drop
The GdkDisplay
that the drop belongs to.
The GdkDrag
that initiated this drop
The possible formats that the drop can provide its data in.
The GdkSurface
the drop happens on
Creates a binding between source_property
on source
and target_property
on target
.
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.
the property on source
to bind
the target #GObject
the property on target
to bind
flags to pass to #GBinding
Creates a binding between source_property
on source
and target_property
on target,
allowing you to set the transformation functions to be used by
the binding.
This function is the language bindings friendly version of g_object_bind_property_full(), using #GClosures instead of function pointers.
the property on source
to bind
the target #GObject
the property on target
to bind
flags to pass to #GBinding
a #GClosure wrapping the transformation function from the source
to the target,
or %NULL to use the default
a #GClosure wrapping the transformation function from the target
to the source,
or %NULL to use the default
Ends the drag operation after a drop.
The action
must be a single action selected from the actions
available via [methodGdk
.Drop.get_actions].
the action performed by the destination or 0 if the drop failed
This function is intended for #GObject implementations to re-enforce a [floating][floating-ref] object reference. Doing this is seldom required: all #GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().
Increases the freeze count on object
. If the freeze count is
non-zero, the emission of "notify" signals on object
is
stopped. The signals are queued until the freeze count is decreased
to zero. Duplicate notifications are squashed so that at most one
#GObject::notify signal is emitted for each property modified while the
object is frozen.
This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.
Returns the possible actions for this GdkDrop
.
If this value contains multiple actions - i.e.
[funcGdk
.DragAction.is_unique] returns %FALSE for the result -
[methodGdk
.Drop.finish] must choose the action to use when
accepting the drop. This will only happen if you passed
%GDK_ACTION_ASK as one of the possible actions in
[methodGdk
.Drop.status]. %GDK_ACTION_ASK itself will not
be included in the actions returned by this function.
This value may change over the lifetime of the [classGdk
.Drop]
both as a response to source side actions as well as to calls to
[methodGdk
.Drop.status] or [methodGdk
.Drop.finish]. The source
side will not change this value anymore once a drop has started.
Gets a named field from the objects table of associations (see g_object_set_data()).
name of the key for that association
If this is an in-app drag-and-drop operation, returns the GdkDrag
that corresponds to this drop.
If it is not, %NULL is returned.
Returns the GdkContentFormats
that the drop offers the data
to be read in.
Gets a property of an object.
The value
can be:
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.
the name of the property to get
return location for the property value
This function gets back user data pointers stored via g_object_set_qdata().
A #GQuark, naming the user data pointer
Gets n_properties
properties for an object
.
Obtained properties will be set to values
. All properties must be valid.
Warnings will be emitted and undefined behaviour may result if invalid
properties are passed in.
the names of each property to get
the values of each property to get
Checks whether object
has a [floating][floating-ref] reference.
Emits a "notify" signal for the property property_name
on object
.
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.
the name of a property installed on the class of object
.
Emits a "notify" signal for the property specified by pspec
on object
.
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]);
the #GParamSpec of a property installed on the class of object
.
Asynchronously read the dropped data from a GdkDrop
in a format that complies with one of the mime types.
pointer to an array of mime types
the I/O priority for the read operation
optional GCancellable
object
a GAsyncReadyCallback
to call when the request is satisfied
Finishes an async drop read operation.
Note that you must not use blocking read calls on the returned stream in the GTK thread, since some platforms might require communication with GTK to complete the data transfer. You can use async APIs such as g_input_stream_read_bytes_async().
See [methodGdk
.Drop.read_async].
a GAsyncResult
Asynchronously request the drag operation's contents converted
to the given type
.
When the operation is finished callback
will be called. You must
then call [methodGdk
.Drop.read_value_finish] to get the resulting
GValue
.
For local drag-and-drop operations that are available in the given
GType
, the value will be copied directly. Otherwise, GDK will
try to use [funcGdk
.content_deserialize_async] to convert the data.
a GType
to read
the I/O priority of the request.
optional GCancellable
object, %NULL to ignore.
callback to call when the request is satisfied
Finishes an async drop read.
See [methodGdk
.Drop.read_value_async].
a GAsyncResult
Increase the reference count of object,
and possibly remove the
[floating][floating-ref] reference, if object
has a floating reference.
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().
Releases all references to other objects. This can be used to break reference cycles.
This function should only be called from object system implementations.
Each object carries around a table of associations from strings to pointers. This function lets you set an association.
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.
name of the key
data to associate with that key
Sets a property on an object.
the name of the property to set
the value
Selects all actions that are potentially supported by the destination.
When calling this function, do not restrict the passed in actions to
the ones provided by [methodGdk
.Drop.get_actions]. Those actions may
change in the future, even depending on the actions you provide here.
The preferred
action is a hint to the drag-and-drop mechanism about which
action to use when multiple actions are possible.
This function should be called by drag destinations in response to %GDK_DRAG_ENTER or %GDK_DRAG_MOTION events. If the destination does not yet know the exact actions it supports, it should set any possible actions first and then later call this function again.
Supported actions of the destination, or 0 to indicate that a drop will not be accepted
A unique action that's a member of actions
indicating the preferred action
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
name of the key
This function gets back user data pointers stored via
g_object_set_qdata() and removes the data
from object
without invoking its destroy() function (if any was
set).
Usually, calling this function is only required to update
user data pointers with a destroy notifier, for example:
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().
A #GQuark, naming the user data pointer
Reverts the effect of a previous call to
g_object_freeze_notify(). The freeze count is decreased on object
and when it reaches zero, queued "notify" signals are emitted.
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.
Decreases the reference count of object
. When its reference count
drops to 0, the object is finalized (i.e. its memory is freed).
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.
This function essentially limits the life time of the closure
to
the life time of the object. That is, when the object is finalized,
the closure
is invalidated by calling g_closure_invalidate() on
it, in order to prevent invocations of the closure with a finalized
(nonexisting) object. Also, g_object_ref() and g_object_unref() are
added as marshal guards to the closure,
to ensure that an extra
reference count is held on object
during invocation of the
closure
. Usually, this function will be called on closures that
use this object
as closure data.
#GClosure to watch
Find the #GParamSpec with the given name for an
interface. Generally, the interface vtable passed in as g_iface
will be the default vtable from g_type_default_interface_ref(), or,
if you know the interface has already been loaded,
g_type_default_interface_peek().
any interface vtable for the interface, or the default vtable for the interface
name of a property to look up.
Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created #GParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.
This function is meant to be called from the interface's default
vtable initialization function (the class_init
member of
#GTypeInfo.) It must not be called after after class_init
has
been called for any object types implementing this interface.
If pspec
is a floating reference, it will be consumed.
any interface vtable for the interface, or the default vtable for the interface.
the #GParamSpec for the new property
Lists the properties of an interface.Generally, the interface
vtable passed in as g_iface
will be the default vtable from
g_type_default_interface_ref(), or, if you know the interface has
already been loaded, g_type_default_interface_peek().
any interface vtable for the interface, or the default vtable for the interface
Creates a new instance of a #GObject subtype and sets its properties.
Construction parameters (see %G_PARAM_CONSTRUCT, %G_PARAM_CONSTRUCT_ONLY) which are not explicitly specified are set to their default values.
the type id of the #GObject subtype to instantiate
an array of #GParameter
The
GdkDrop
object represents the target of an ongoing DND operation.Possible drop sites get informed about the status of the ongoing drag operation with events of type %GDK_DRAG_ENTER, %GDK_DRAG_LEAVE, %GDK_DRAG_MOTION and %GDK_DROP_START. The
GdkDrop
object can be obtained from these [classGdk
.Event] types using [methodGdk
.DNDEvent.get_drop].The actual data transfer is initiated from the target side via an async read, using one of the
GdkDrop
methods for this purpose: [methodGdk
.Drop.read_async] or [methodGdk
.Drop.read_value_async].GTK provides a higher level abstraction based on top of these functions, and so they are not normally needed in GTK applications. See the "Drag and Drop" section of the GTK documentation for more information.