Class
GtkDragSource
Description [src]
final class Gtk.DragSource : Gtk.GestureSingle
{
/* No available fields */
}GtkDragSource is an event controller to initiate Drag-And-Drop operations.
GtkDragSource can be set up with the necessary
ingredients for a DND operation ahead of time. This includes
the source for the data that is being transferred, in the form
of a GdkContentProvider, the desired action, and the icon to
use during the drag operation. After setting it up, the drag
source must be added to a widget as an event controller, using
gtk_widget_add_controller().
static void
my_widget_init (MyWidget *self)
{
GtkDragSource *drag_source = gtk_drag_source_new ();
g_signal_connect (drag_source, "prepare", G_CALLBACK (on_drag_prepare), self);
g_signal_connect (drag_source, "drag-begin", G_CALLBACK (on_drag_begin), self);
gtk_widget_add_controller (GTK_WIDGET (self), GTK_EVENT_CONTROLLER (drag_source));
}
Setting up the content provider and icon ahead of time only makes
sense when the data does not change. More commonly, you will want
to set them up just in time. To do so, GtkDragSource has
GtkDragSource::prepare and GtkDragSource::drag-begin signals.
The ::prepare signal is emitted before a drag is started, and can be used to set the content provider and actions that the drag should be started with.
static GdkContentProvider *
on_drag_prepare (GtkDragSource *source,
double x,
double y,
MyWidget *self)
{
// This widget supports two types of content: GFile objects
// and GdkPixbuf objects; GTK will handle the serialization
// of these types automatically
GFile *file = my_widget_get_file (self);
GdkPixbuf *pixbuf = my_widget_get_pixbuf (self);
return gdk_content_provider_new_union ((GdkContentProvider *[2]) {
gdk_content_provider_new_typed (G_TYPE_FILE, file),
gdk_content_provider_new_typed (GDK_TYPE_PIXBUF, pixbuf),
}, 2);
}
The ::drag-begin signal is emitted after the GdkDrag object has
been created, and can be used to set up the drag icon.
static void
on_drag_begin (GtkDragSource *source,
GdkDrag *drag,
MyWidget *self)
{
// Set the widget as the drag icon
GdkPaintable *paintable = gtk_widget_paintable_new (GTK_WIDGET (self));
gtk_drag_source_set_icon (source, paintable, 0, 0);
g_object_unref (paintable);
}
During the DND operation, GtkDragSource emits signals that
can be used to obtain updates about the status of the operation,
but it is not normally necessary to connect to any signals,
except for one case: when the supported actions include
GDK_ACTION_MOVE, you need to listen for the
GtkDragSource::drag-end signal and delete the
data after it has been transferred.
Instance methods
Methods inherited from GtkGestureSingle (8)
gtk_gesture_single_get_button
Returns the button number gesture listens for.
gtk_gesture_single_get_current_button
Returns the button number currently interacting
with gesture, or 0 if there is none.
gtk_gesture_single_get_current_sequence
Returns the event sequence currently interacting with gesture.
gtk_gesture_single_get_exclusive
Gets whether a gesture is exclusive.
gtk_gesture_single_get_touch_only
Returns TRUE if the gesture is only triggered by touch events.
gtk_gesture_single_set_button
Sets the button number gesture listens to.
gtk_gesture_single_set_exclusive
Sets whether gesture is exclusive.
gtk_gesture_single_set_touch_only
Sets whether to handle only touch events.
Methods inherited from GtkGesture (17)
gtk_gesture_get_bounding_box
If there are touch sequences being currently handled by gesture,
returns TRUE and fills in rect with the bounding box containing
all active touches.
gtk_gesture_get_bounding_box_center
If there are touch sequences being currently handled by gesture,
returns TRUE and fills in x and y with the center of the bounding
box containing all active touches.
gtk_gesture_get_device
Returns the logical GdkDevice that is currently operating
on gesture.
gtk_gesture_get_group
Returns all gestures in the group of gesture.
gtk_gesture_get_last_event
Returns the last event that was processed for sequence.
gtk_gesture_get_last_updated_sequence
Returns the GdkEventSequence that was last updated on gesture.
gtk_gesture_get_point
If sequence is currently being interpreted by gesture,
returns TRUE and fills in x and y with the last coordinates
stored for that event sequence.
gtk_gesture_get_sequence_state
Returns the sequence state, as seen by gesture.
gtk_gesture_get_sequences
Returns the list of GdkEventSequences currently being interpreted
by gesture.
gtk_gesture_group
Adds gesture to the same group than group_gesture.
gtk_gesture_handles_sequence
Returns TRUE if gesture is currently handling events
corresponding to sequence.
gtk_gesture_is_active
Returns TRUE if the gesture is currently active.
gtk_gesture_is_grouped_with
Returns TRUE if both gestures pertain to the same group.
gtk_gesture_is_recognized
Returns TRUE if the gesture is currently recognized.
gtk_gesture_set_sequence_state
Sets the state of sequence in gesture.
deprecated: 4.10.
gtk_gesture_set_state
Sets the state of all sequences that gesture is currently
interacting with.
gtk_gesture_ungroup
Separates gesture into an isolated group.
Methods inherited from GtkEventController (13)
gtk_event_controller_get_current_event
Returns the event that is currently being handled by the controller.
gtk_event_controller_get_current_event_device
Returns the device of the event that is currently being handled by the controller.
gtk_event_controller_get_current_event_state
Returns the modifier state of the event that is currently being handled by the controller.
gtk_event_controller_get_current_event_time
Returns the timestamp of the event that is currently being handled by the controller.
gtk_event_controller_get_name
Gets the name of controller.
gtk_event_controller_get_propagation_limit
Gets the propagation limit of the event controller.
gtk_event_controller_get_propagation_phase
Gets the propagation phase at which controller handles events.
gtk_event_controller_get_widget
Returns the GtkWidget this controller relates to.
gtk_event_controller_reset
Resets the controller to a clean state.
gtk_event_controller_set_name
Sets a name on the controller that can be used for debugging.
gtk_event_controller_set_propagation_limit
Sets the event propagation limit on the event controller.
gtk_event_controller_set_propagation_phase
Sets the propagation phase at which a controller handles events.
gtk_event_controller_set_static_name
Sets a name on the controller that can be used for debugging.
since: 4.8
Properties
Properties inherited from GtkGestureSingle (3)
Gtk.GestureSingle:button
Mouse button number to listen to, or 0 to listen for any button.
Gtk.GestureSingle:exclusive
Whether the gesture is exclusive.
Gtk.GestureSingle:touch-only
Whether the gesture handles only touch events.
Properties inherited from GtkGesture (1)
Properties inherited from GtkEventController (4)
Gtk.EventController:name
The name for this controller, typically used for debugging purposes.
Gtk.EventController:propagation-limit
The limit for which events this controller will handle.
Gtk.EventController:propagation-phase
The propagation phase at which this controller will handle events.
Gtk.EventController:widget
The widget receiving the GdkEvents that the controller will handle.
Signals
Signals inherited from GtkGesture (5)
GtkGesture::begin
Emitted when the gesture is recognized.
GtkGesture::cancel
Emitted whenever a sequence is cancelled.
GtkGesture::end
Emitted when gesture either stopped recognizing the event
sequences as something to be handled, or the number of touch
sequences became higher or lower than GtkGesture:n-points.
GtkGesture::sequence-state-changed
Emitted whenever a sequence state changes.
GtkGesture::update
Emitted whenever an event is handled while the gesture is recognized.
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.