DropTargetAsync

GtkDropTargetAsync is an event controller to receive Drag-and-Drop operations, asynchronously.

It is the more complete but also more complex method of handling drop operations compared to [class@Gtk.DropTarget], and you should only use it if GtkDropTarget doesn't provide all the features you need.

To use a GtkDropTargetAsync to receive drops on a widget, you create a GtkDropTargetAsync object, configure which data formats and actions you support, connect to its signals, and then attach it to the widget with [method@Gtk.Widget.add_controller].

During a drag operation, the first signal that a GtkDropTargetAsync emits is [signal@Gtk.DropTargetAsync::accept], which is meant to determine whether the target is a possible drop site for the ongoing drop. The default handler for the ::accept signal accepts the drop if it finds a compatible data format and an action that is supported on both sides.

If it is, and the widget becomes a target, you will receive a [signal@Gtk.DropTargetAsync::drag-enter] signal, followed by [signal@Gtk.DropTargetAsync::drag-motion] signals as the pointer moves, optionally a [signal@Gtk.DropTargetAsync::drop] signal when a drop happens, and finally a [signal@Gtk.DropTargetAsync::drag-leave] signal when the pointer moves off the widget.

The ::drag-enter and ::drag-motion handler return a GdkDragAction to update the status of the ongoing operation. The ::drop handler should decide if it ultimately accepts the drop and if it does, it should initiate the data transfer and finish the operation by calling [method@Gdk.Drop.finish].

Between the ::drag-enter and ::drag-leave signals the widget is a current drop target, and will receive the %GTK_STATE_FLAG_DROP_ACTIVE state, which can be used by themes to style the widget as a drop target.

class DropTargetAsync : EventController {

protected

GtkDropTargetAsync* gtkDropTargetAsync;

GtkDropTargetAsync* getDropTargetAsyncStruct(bool transferOwnership);

void* getStruct();

this(GtkDropTargetAsync* gtkDropTargetAsync, bool ownedRef);

static GType getType();

this(ContentFormats formats, GdkDragAction actions);

GdkDragAction getActions();

ContentFormats getFormats();

void rejectDrop(Drop drop);

void setActions(GdkDragAction actions);

void setFormats(ContentFormats formats);

gulong addOnAccept(bool delegate(Drop, DropTargetAsync) dlg, ConnectFlags connectFlags);

gulong addOnDragEnter(GdkDragAction delegate(Drop, double, double, DropTargetAsync) dlg, ConnectFlags connectFlags);

gulong addOnDragLeave(void delegate(Drop, DropTargetAsync) dlg, ConnectFlags connectFlags);

gulong addOnDragMotion(GdkDragAction delegate(Drop, double, double, DropTargetAsync) dlg, ConnectFlags connectFlags);

gulong addOnDrop(bool delegate(Drop, double, double, DropTargetAsync) dlg, ConnectFlags connectFlags);

}

Constructors

this this(GtkDropTargetAsync* gtkDropTargetAsync, bool ownedRef): Sets our main struct and passes it to the parent class.
this this(ContentFormats formats, GdkDragAction actions): Creates a new GtkDropTargetAsync object.

Members

Functions

addOnAccept gulong addOnAccept(bool delegate(Drop, DropTargetAsync) dlg, ConnectFlags connectFlags): Emitted on the drop site when a drop operation is about to begin.
addOnDragEnter gulong addOnDragEnter(GdkDragAction delegate(Drop, double, double, DropTargetAsync) dlg, ConnectFlags connectFlags): Emitted on the drop site when the pointer enters the widget.
addOnDragLeave gulong addOnDragLeave(void delegate(Drop, DropTargetAsync) dlg, ConnectFlags connectFlags): Emitted on the drop site when the pointer leaves the widget.
addOnDragMotion gulong addOnDragMotion(GdkDragAction delegate(Drop, double, double, DropTargetAsync) dlg, ConnectFlags connectFlags): Emitted while the pointer is moving over the drop target.
addOnDrop gulong addOnDrop(bool delegate(Drop, double, double, DropTargetAsync) dlg, ConnectFlags connectFlags): Emitted on the drop site when the user drops the data onto the widget.
getActions GdkDragAction getActions(): Gets the actions that this drop target supports.
getDropTargetAsyncStruct GtkDropTargetAsync* getDropTargetAsyncStruct(bool transferOwnership): Get the main Gtk struct
getFormats ContentFormats getFormats(): Gets the data formats that this drop target accepts.
getStruct void* getStruct(): the main Gtk struct as a void*
rejectDrop void rejectDrop(Drop drop): Sets the @drop as not accepted on this drag site.
setActions void setActions(GdkDragAction actions): Sets the actions that this drop target supports.
setFormats void setFormats(ContentFormats formats): Sets the data formats that this drop target will accept.

Static functions

getType GType getType()

Variables

gtkDropTargetAsync GtkDropTargetAsync* gtkDropTargetAsync;: the main Gtk struct

Inherited Members

From EventController

gtkEventController GtkEventController* gtkEventController;: the main Gtk struct
getEventControllerStruct GtkEventController* getEventControllerStruct(bool transferOwnership): Get the main Gtk struct
getStruct void* getStruct(): the main Gtk struct as a void*
getType GType getType()
getCurrentEvent Event getCurrentEvent(): Returns the event that is currently being handled by the controller, and %NULL at other times.
getCurrentEventDevice Device getCurrentEventDevice(): Returns the device of the event that is currently being handled by the controller, and %NULL otherwise.
getCurrentEventState GdkModifierType getCurrentEventState(): Returns the modifier state of the event that is currently being handled by the controller, and 0 otherwise.
getCurrentEventTime uint getCurrentEventTime(): Returns the timestamp of the event that is currently being handled by the controller, and 0 otherwise.
getName string getName(): Gets the name of @controller.
getPropagationLimit GtkPropagationLimit getPropagationLimit(): Gets the propagation limit of the event controller.
getPropagationPhase GtkPropagationPhase getPropagationPhase(): Gets the propagation phase at which @controller handles events.
getWidget Widget getWidget(): Returns the #GtkWidget this controller relates to.
reset void reset(): Resets the @controller to a clean state.
setName void setName(string name): Sets a name on the controller that can be used for debugging.
setPropagationLimit void setPropagationLimit(GtkPropagationLimit limit): Sets the event propagation limit on the event controller.
setPropagationPhase void setPropagationPhase(GtkPropagationPhase phase): Sets the propagation phase at which a controller handles events.