/* GDK - The GIMP Drawing Kit
* Copyright (C) 1995-1999 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* Modified by the GTK+ Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GTK+ Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GTK+ at ftp://ftp.gtk.org/pub/gtk/.
*/
#include "config.h"
#include "gdkdndprivate.h"
#include "gdkdisplay.h"
#include "gdkwindow.h"
#include "gdkintl.h"
#include "gdkenumtypes.h"
#include "gdkcursor.h"
static struct {
GdkDragAction action;
const gchar *name;
GdkCursor *cursor;
} drag_cursors[] = {
{ GDK_ACTION_DEFAULT, NULL, NULL },
{ GDK_ACTION_ASK, "dnd-ask", NULL },
{ GDK_ACTION_COPY, "dnd-copy", NULL },
{ GDK_ACTION_MOVE, "dnd-move", NULL },
{ GDK_ACTION_LINK, "dnd-link", NULL },
{ 0, "dnd-none", NULL },
};
enum {
CANCEL,
DROP_PERFORMED,
DND_FINISHED,
ACTION_CHANGED,
N_SIGNALS
};
static guint signals[N_SIGNALS] = { 0 };
static GList *contexts = NULL;
/**
* SECTION:dnd
* @title: Drag And Drop
* @short_description: Functions for controlling drag and drop handling
*
* These functions provide a low level interface for drag and drop.
* The X backend of GDK supports both the Xdnd and Motif drag and drop
* protocols transparently, the Win32 backend supports the WM_DROPFILES
* protocol.
*
* 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][gtk3-Drag-and-Drop] section of
* the GTK+ documentation for more information.
*/
/**
* gdk_drag_context_list_targets:
* @context: a #GdkDragContext
*
* Retrieves the list of targets of the context.
*
* Returns: (transfer none) (element-type GdkAtom): a #GList of targets
*
* Since: 2.22
**/
GList *
gdk_drag_context_list_targets (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), NULL);
return context->targets;
}
/**
* gdk_drag_context_get_actions:
* @context: a #GdkDragContext
*
* Determines the bitmask of actions proposed by the source if
* gdk_drag_context_get_suggested_action() returns %GDK_ACTION_ASK.
*
* Returns: the #GdkDragAction flags
*
* Since: 2.22
**/
GdkDragAction
gdk_drag_context_get_actions (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), GDK_ACTION_DEFAULT);
return context->actions;
}
/**
* gdk_drag_context_get_suggested_action:
* @context: a #GdkDragContext
*
* Determines the suggested drag action of the context.
*
* Returns: a #GdkDragAction value
*
* Since: 2.22
**/
GdkDragAction
gdk_drag_context_get_suggested_action (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), 0);
return context->suggested_action;
}
/**
* gdk_drag_context_get_selected_action:
* @context: a #GdkDragContext
*
* Determines the action chosen by the drag destination.
*
* Returns: a #GdkDragAction value
*
* Since: 2.22
**/
GdkDragAction
gdk_drag_context_get_selected_action (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), 0);
return context->action;
}
/**
* gdk_drag_context_get_source_window:
* @context: a #GdkDragContext
*
* Returns the #GdkWindow where the DND operation started.
*
* Returns: (transfer none): a #GdkWindow
*
* Since: 2.22
**/
GdkWindow *
gdk_drag_context_get_source_window (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), NULL);
return context->source_window;
}
/**
* gdk_drag_context_get_dest_window:
* @context: a #GdkDragContext
*
* Returns the destination windw for the DND operation.
*
* Returns: (transfer none): a #GdkWindow
*
* Since: 3.0
**/
GdkWindow *
gdk_drag_context_get_dest_window (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), NULL);
return context->dest_window;
}
/**
* gdk_drag_context_get_protocol:
* @context: a #GdkDragContext
*
* Returns the drag protocol thats used by this context.
*
* Returns: the drag protocol
*
* Since: 3.0
*/
GdkDragProtocol
gdk_drag_context_get_protocol (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), GDK_DRAG_PROTO_NONE);
return context->protocol;
}
/**
* gdk_drag_context_set_device:
* @context: a #GdkDragContext
* @device: a #GdkDevice
*
* Associates a #GdkDevice to @context, so all Drag and Drop events
* for @context are emitted as if they came from this device.
*/
void
gdk_drag_context_set_device (GdkDragContext *context,
GdkDevice *device)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
g_return_if_fail (GDK_IS_DEVICE (device));
if (context->device)
g_object_unref (context->device);
context->device = device;
if (context->device)
g_object_ref (context->device);
}
/**
* gdk_drag_context_get_device:
* @context: a #GdkDragContext
*
* Returns the #GdkDevice associated to the drag context.
*
* Returns: (transfer none): The #GdkDevice associated to @context.
**/
GdkDevice *
gdk_drag_context_get_device (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), NULL);
return context->device;
}
G_DEFINE_TYPE (GdkDragContext, gdk_drag_context, G_TYPE_OBJECT)
static void
gdk_drag_context_init (GdkDragContext *context)
{
contexts = g_list_prepend (contexts, context);
}
static void
gdk_drag_context_finalize (GObject *object)
{
GdkDragContext *context = GDK_DRAG_CONTEXT (object);
contexts = g_list_remove (contexts, context);
g_list_free (context->targets);
if (context->source_window)
g_object_unref (context->source_window);
if (context->dest_window)
g_object_unref (context->dest_window);
G_OBJECT_CLASS (gdk_drag_context_parent_class)->finalize (object);
}
static void
gdk_drag_context_class_init (GdkDragContextClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->finalize = gdk_drag_context_finalize;
/**
* GdkDragContext::cancel:
* @context: The object on which the signal is emitted
* @reason: The reason the context was cancelled
*
* The drag and drop operation was cancelled.
*
* This signal will only be emitted if the #GdkDragContext manages
* the drag and drop operation. See gdk_drag_context_manage_dnd()
* for more information.
*
* Since: 3.20
*/
signals[CANCEL] =
g_signal_new ("cancel",
G_TYPE_FROM_CLASS (object_class),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GdkDragContextClass, cancel),
NULL, NULL,
g_cclosure_marshal_VOID__ENUM,
G_TYPE_NONE, 1, GDK_TYPE_DRAG_CANCEL_REASON);
/**
* GdkDragContext::drop-performed:
* @context: The object on which the signal is emitted
* @time: the time at which the drop happened.
*
* The drag and drop operation was performed on an accepting client.
*
* This signal will only be emitted if the #GdkDragContext manages
* the drag and drop operation. See gdk_drag_context_manage_dnd()
* for more information.
*
* Since: 3.20
*/
signals[DROP_PERFORMED] =
g_signal_new ("drop-performed",
G_TYPE_FROM_CLASS (object_class),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GdkDragContextClass, drop_performed),
NULL, NULL,
g_cclosure_marshal_VOID__INT,
G_TYPE_NONE, 1, G_TYPE_INT);
/**
* GdkDragContext::dnd-finished:
* @context: The object on which the signal is emitted
*
* The drag and drop operation was finished, the drag destination
* finished reading all data. The drag source can now free all
* miscellaneous data.
*
* This signal will only be emitted if the #GdkDragContext manages
* the drag and drop operation. See gdk_drag_context_manage_dnd()
* for more information.
*
* Since: 3.20
*/
signals[DND_FINISHED] =
g_signal_new ("dnd-finished",
G_TYPE_FROM_CLASS (object_class),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GdkDragContextClass, dnd_finished),
NULL, NULL,
g_cclosure_marshal_VOID__VOID,
G_TYPE_NONE, 0);
/**
* GdkDragContext::action-changed:
* @context: The object on which the signal is emitted
* @action: The action currently chosen
*
* A new action is being chosen for the drag and drop operation.
*
* This signal will only be emitted if the #GdkDragContext manages
* the drag and drop operation. See gdk_drag_context_manage_dnd()
* for more information.
*
* Since: 3.20
*/
signals[ACTION_CHANGED] =
g_signal_new ("action-changed",
G_TYPE_FROM_CLASS (object_class),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GdkDragContextClass, action_changed),
NULL, NULL,
g_cclosure_marshal_VOID__FLAGS,
G_TYPE_NONE, 1, GDK_TYPE_DRAG_ACTION);
}
/**
* gdk_drag_find_window_for_screen:
* @context: a #GdkDragContext
* @drag_window: a window which may be at the pointer position, but
* should be ignored, since it is put up by the drag source as an icon
* @screen: the screen where the destination window is sought
* @x_root: the x position of the pointer in root coordinates
* @y_root: the y position of the pointer in root coordinates
* @dest_window: (out): location to store the destination window in
* @protocol: (out): location to store the DND protocol in
*
* Finds the destination window and DND protocol to use at the
* given pointer position.
*
* This function is called by the drag source to obtain the
* @dest_window and @protocol parameters for gdk_drag_motion().
*
* Since: 2.2
*/
void
gdk_drag_find_window_for_screen (GdkDragContext *context,
GdkWindow *drag_window,
GdkScreen *screen,
gint x_root,
gint y_root,
GdkWindow **dest_window,
GdkDragProtocol *protocol)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
*dest_window = GDK_DRAG_CONTEXT_GET_CLASS (context)
->find_window (context, drag_window, screen, x_root, y_root, protocol);
}
/**
* gdk_drag_status:
* @context: a #GdkDragContext
* @action: the selected action which will be taken when a drop happens,
* or 0 to indicate that a drop will not be accepted
* @time_: the timestamp for this operation
*
* Selects one of the actions offered by the drag source.
*
* This function is called by the drag destination in response to
* gdk_drag_motion() called by the drag source.
*/
void
gdk_drag_status (GdkDragContext *context,
GdkDragAction action,
guint32 time_)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
GDK_DRAG_CONTEXT_GET_CLASS (context)->drag_status (context, action, time_);
}
/**
* gdk_drag_motion:
* @context: a #GdkDragContext
* @dest_window: the new destination window, obtained by
* gdk_drag_find_window()
* @protocol: the DND protocol in use, obtained by gdk_drag_find_window()
* @x_root: the x position of the pointer in root coordinates
* @y_root: the y position of the pointer in root coordinates
* @suggested_action: the suggested action
* @possible_actions: the possible actions
* @time_: the timestamp for this operation
*
* Updates the drag context when the pointer moves or the
* set of actions changes.
*
* This function is called by the drag source.
*
* This function does not need to be called in managed drag and drop
* operations. See gdk_drag_context_manage_dnd() for more information.
*
* Returns:
*/
gboolean
gdk_drag_motion (GdkDragContext *context,
GdkWindow *dest_window,
GdkDragProtocol protocol,
gint x_root,
gint y_root,
GdkDragAction suggested_action,
GdkDragAction possible_actions,
guint32 time_)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), FALSE);
return GDK_DRAG_CONTEXT_GET_CLASS (context)
->drag_motion (context,
dest_window,
protocol,
x_root,
y_root,
suggested_action,
possible_actions,
time_);
}
/**
* gdk_drag_abort:
* @context: a #GdkDragContext
* @time_: the timestamp for this operation
*
* Aborts a drag without dropping.
*
* This function is called by the drag source.
*
* This function does not need to be called in managed drag and drop
* operations. See gdk_drag_context_manage_dnd() for more information.
*/
void
gdk_drag_abort (GdkDragContext *context,
guint32 time_)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
GDK_DRAG_CONTEXT_GET_CLASS (context)->drag_abort (context, time_);
}
/**
* gdk_drag_drop:
* @context: a #GdkDragContext
* @time_: the timestamp for this operation
*
* Drops on the current destination.
*
* This function is called by the drag source.
*
* This function does not need to be called in managed drag and drop
* operations. See gdk_drag_context_manage_dnd() for more information.
*/
void
gdk_drag_drop (GdkDragContext *context,
guint32 time_)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
GDK_DRAG_CONTEXT_GET_CLASS (context)->drag_drop (context, time_);
}
/**
* gdk_drop_reply:
* @context: a #GdkDragContext
* @accepted: %TRUE if the drop is accepted
* @time_: the timestamp for this operation
*
* Accepts or rejects a drop.
*
* This function is called by the drag destination in response
* to a drop initiated by the drag source.
*/
void
gdk_drop_reply (GdkDragContext *context,
gboolean accepted,
guint32 time_)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
GDK_DRAG_CONTEXT_GET_CLASS (context)->drop_reply (context, accepted, time_);
}
/**
* gdk_drop_finish:
* @context: a #GdkDragContext
* @success: %TRUE if the data was successfully received
* @time_: the timestamp for this operation
*
* Ends the drag operation after a drop.
*
* This function is called by the drag destination.
*/
void
gdk_drop_finish (GdkDragContext *context,
gboolean success,
guint32 time_)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
GDK_DRAG_CONTEXT_GET_CLASS (context)->drop_finish (context, success, time_);
}
/**
* gdk_drag_drop_succeeded:
* @context: a #GdkDragContext
*
* Returns whether the dropped data has been successfully
* transferred. This function is intended to be used while
* handling a %GDK_DROP_FINISHED event, its return value is
* meaningless at other times.
*
* Returns: %TRUE if the drop was successful.
*
* Since: 2.6
**/
gboolean
gdk_drag_drop_succeeded (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), FALSE);
return GDK_DRAG_CONTEXT_GET_CLASS (context)->drop_status (context);
}
/**
* gdk_drag_get_selection:
* @context: a #GdkDragContext.
*
* Returns the selection atom for the current source window.
*
* Returns: (transfer none): the selection atom, or %GDK_NONE
*/
GdkAtom
gdk_drag_get_selection (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), GDK_NONE);
return GDK_DRAG_CONTEXT_GET_CLASS (context)->get_selection (context);
}
/**
* gdk_drag_context_get_drag_window:
* @context: a #GdkDragContext
*
* Returns the window on which the drag icon should be rendered
* during the drag operation. Note that the window may not be
* available until the drag operation has begun. GDK will move
* the window in accordance with the ongoing drag operation.
* The window is owned by @context and will be destroyed when
* the drag operation is over.
*
* Returns: (nullable) (transfer none): the drag window, or %NULL
*
* Since: 3.20
*/
GdkWindow *
gdk_drag_context_get_drag_window (GdkDragContext *context)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), NULL);
if (GDK_DRAG_CONTEXT_GET_CLASS (context)->get_drag_window)
return GDK_DRAG_CONTEXT_GET_CLASS (context)->get_drag_window (context);
return NULL;
}
/**
* gdk_drag_context_set_hotspot:
* @context: a #GdkDragContext
* @hot_x: x coordinate of the drag window hotspot
* @hot_y: y coordinate of the drag window hotspot
*
* Sets the position of the drag window that will be kept
* under the cursor hotspot. Initially, the hotspot is at the
* top left corner of the drag window.
*
* Since: 3.20
*/
void
gdk_drag_context_set_hotspot (GdkDragContext *context,
gint hot_x,
gint hot_y)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
if (GDK_DRAG_CONTEXT_GET_CLASS (context)->set_hotspot)
GDK_DRAG_CONTEXT_GET_CLASS (context)->set_hotspot (context, hot_x, hot_y);
}
/**
* gdk_drag_drop_done:
* @context: a #GdkDragContext
* @success: whether the drag was ultimatively successful
*
* Inform GDK if the drop ended successfully. Passing %FALSE
* for @success may trigger a drag cancellation animation.
*
* This function is called by the drag source, and should
* be the last call before dropping the reference to the
* @context.
*
* The #GdkDragContext will only take the first gdk_drag_drop_done()
* call as effective, if this function is called multiple times,
* all subsequent calls will be ignored.
*
* Since: 3.20
*/
void
gdk_drag_drop_done (GdkDragContext *context,
gboolean success)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
if (context->drop_done)
return;
context->drop_done = TRUE;
if (GDK_DRAG_CONTEXT_GET_CLASS (context)->drop_done)
GDK_DRAG_CONTEXT_GET_CLASS (context)->drop_done (context, success);
}
/**
* gdk_drag_context_manage_dnd:
* @context: a #GdkDragContext
* @ipc_window: Window to use for IPC messaging/events
* @actions: the actions supported by the drag source
*
* Requests the drag and drop operation to be managed by @context.
* When a drag and drop operation becomes managed, the #GdkDragContext
* will internally handle all input and source-side #GdkEventDND events
* as required by the windowing system.
*
* Once the drag and drop operation is managed, the drag context will
* emit the following signals:
* - The #GdkDragContext::action-changed signal whenever the final action
* to be performed by the drag and drop operation changes.
* - The #GdkDragContext::drop-performed signal after the user performs
* the drag and drop gesture (typically by releasing the mouse button).
* - The #GdkDragContext::dnd-finished signal after the drag and drop
* operation concludes (after all #GdkSelection transfers happen).
* - The #GdkDragContext::cancel signal if the drag and drop operation is
* finished but doesn't happen over an accepting destination, or is
* cancelled through other means.
*
* Returns: #TRUE if the drag and drop operation is managed.
*
* Since: 3.20
**/
gboolean
gdk_drag_context_manage_dnd (GdkDragContext *context,
GdkWindow *ipc_window,
GdkDragAction actions)
{
g_return_val_if_fail (GDK_IS_DRAG_CONTEXT (context), FALSE);
g_return_val_if_fail (GDK_IS_WINDOW (ipc_window), FALSE);
if (GDK_DRAG_CONTEXT_GET_CLASS (context)->manage_dnd)
return GDK_DRAG_CONTEXT_GET_CLASS (context)->manage_dnd (context, ipc_window, actions);
return FALSE;
}
void
gdk_drag_context_set_cursor (GdkDragContext *context,
GdkCursor *cursor)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
if (GDK_DRAG_CONTEXT_GET_CLASS (context)->set_cursor)
GDK_DRAG_CONTEXT_GET_CLASS (context)->set_cursor (context, cursor);
}
void
gdk_drag_context_cancel (GdkDragContext *context,
GdkDragCancelReason reason)
{
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
g_signal_emit (context, signals[CANCEL], 0, reason);
}
GList *
gdk_drag_context_list (void)
{
return contexts;
}
gboolean
gdk_drag_context_handle_source_event (GdkEvent *event)
{
GdkDragContext *context;
GList *l;
for (l = contexts; l; l = l->next)
{
context = l->data;
if (!context->is_source)
continue;
if (!GDK_DRAG_CONTEXT_GET_CLASS (context)->handle_event)
continue;
if (GDK_DRAG_CONTEXT_GET_CLASS (context)->handle_event (context, event))
return TRUE;
}
return FALSE;
}
GdkCursor *
gdk_drag_get_cursor (GdkDragContext *context,
GdkDragAction action)
{
gint i;
for (i = 0 ; i < G_N_ELEMENTS (drag_cursors) - 1; i++)
if (drag_cursors[i].action == action)
break;
if (drag_cursors[i].cursor == NULL)
drag_cursors[i].cursor = gdk_cursor_new_from_name (context->display,
drag_cursors[i].name);
return drag_cursors[i].cursor;
}
static void
gdk_drag_context_commit_drag_status (GdkDragContext *context)
{
GdkDragContextClass *context_class;
g_return_if_fail (GDK_IS_DRAG_CONTEXT (context));
g_return_if_fail (!context->is_source);
context_class = GDK_DRAG_CONTEXT_GET_CLASS (context);
if (context_class->commit_drag_status)
context_class->commit_drag_status (context);
}
gboolean
gdk_drag_context_handle_dest_event (GdkEvent *event)
{
GdkDragContext *context = NULL;
GList *l;
switch (event->type)
{
case GDK_DRAG_MOTION:
case GDK_DROP_START:
context = event->dnd.context;
break;
case GDK_SELECTION_NOTIFY:
for (l = contexts; l; l = l->next)
{
GdkDragContext *c = l->data;
if (!c->is_source &&
event->selection.selection == gdk_drag_get_selection (c))
{
context = c;
break;
}
}
break;
default:
return FALSE;
}
if (!context)
return FALSE;
gdk_drag_context_commit_drag_status (context);
return TRUE;;
}