/* GTK - The GIMP Toolkit * 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 . */ /* * 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 "gtkdndprivate.h" #include "gtkdragdest.h" #include "gtkimageprivate.h" #include "gtkintl.h" #include "gtkmain.h" #include "gtkpicture.h" #include "gtkselectionprivate.h" #include "gtksettingsprivate.h" #include "gtkstylecontext.h" #include "gtktooltipprivate.h" #include "gtkwidgetprivate.h" #include "gtkwindowgroup.h" #include "gtkwindowprivate.h" #include "gtknative.h" #include "gtkdragiconprivate.h" #include "gdk/gdkcontentformatsprivate.h" #include "gdk/gdktextureprivate.h" #include #include #include /** * SECTION:gtkdnd * @Short_description: Functions for controlling drag and drop handling * @Title: Drag and Drop * * GTK+ has a rich set of functions for doing inter-process communication * via the drag-and-drop metaphor. * * As well as the functions listed here, applications may need to use some * facilities provided for [Selections][gtk3-Selections]. Also, the Drag and * Drop API makes use of signals in the #GtkWidget class. */ typedef struct _GtkDragSourceInfo GtkDragSourceInfo; typedef struct _GtkDragDestInfo GtkDragDestInfo; struct _GtkDragSourceInfo { GtkWidget *widget; GdkContentFormats *target_list; /* Targets for drag data */ GdkDrag *drag; /* drag context */ GtkWidget *icon_window; /* Window for drag */ GtkWidget *icon_widget; /* Widget for drag */ guint drop_timeout; /* Timeout for aborting drop */ guint destroy_icon : 1; /* If true, destroy icon_widget */ }; struct _GtkDragDestInfo { GtkWidget *widget; /* Widget in which drag is in */ GdkDrop *drop; /* drop */ }; #define DROP_ABORT_TIME 300000 typedef gboolean (* GtkDragDestCallback) (GtkWidget *widget, GdkDrop *drop, gint x, gint y, guint32 time); /* Forward declarations */ static gboolean gtk_drop_find_widget (GtkWidget *widget, GdkDrop *drop, GtkDragDestInfo *info, gint x, gint y, guint32 time, GtkDragDestCallback callback); static void gtk_drag_dest_leave (GtkWidget *widget, GdkDrop *drop, guint time); static gboolean gtk_drag_dest_motion (GtkWidget *widget, GdkDrop *drop, gint x, gint y, guint time); static gboolean gtk_drag_dest_drop (GtkWidget *widget, GdkDrop *drop, gint x, gint y, guint time); static void gtk_drag_dest_set_widget (GtkDragDestInfo *info, GtkWidget *widget); static GtkDragDestInfo * gtk_drag_get_dest_info (GdkDrop *drop, gboolean create); static GtkDragSourceInfo *gtk_drag_get_source_info (GdkDrag *drag, gboolean create); static void gtk_drag_clear_source_info (GdkDrag *drag); static void gtk_drag_drop (GtkDragSourceInfo *info); static void gtk_drag_drop_finished (GtkDragSourceInfo *info, GtkDragResult result); static void gtk_drag_cancel_internal (GtkDragSourceInfo *info, GtkDragResult result); static void gtk_drag_remove_icon (GtkDragSourceInfo *info); static void gtk_drag_source_info_destroy (GtkDragSourceInfo *info); static void gtk_drag_drop_performed_cb (GdkDrag *drag, GtkDragSourceInfo *info); static void gtk_drag_cancel_cb (GdkDrag *drag, GdkDragCancelReason reason, GtkDragSourceInfo *info); static void gtk_drag_dnd_finished_cb (GdkDrag *drag, GtkDragSourceInfo *info); static gboolean gtk_drag_abort_timeout (gpointer data); static void set_icon_helper (GdkDrag *drag, GtkImageDefinition *def, gint hot_x, gint hot_y); /******************** * Destination side * ********************/ typedef struct { GdkDrop *drop; GtkWidget *widget; const char *mime_type; } GtkDragGetData; static void gtk_drag_get_data_finish (GtkDragGetData *data, guchar *bytes, gsize size) { GtkDragDestSite *site; GtkSelectionData sdata; site = g_object_get_data (G_OBJECT (data->widget), "gtk-drag-dest"); sdata.target = data->mime_type; sdata.type = data->mime_type; sdata.format = 8; sdata.length = size; sdata.data = bytes ? bytes : (guchar *)g_strdup (""); sdata.display = gtk_widget_get_display (data->widget); if (site && site->target_list) { if (gdk_content_formats_contain_mime_type (site->target_list, data->mime_type)) { if (!(site->flags & GTK_DEST_DEFAULT_DROP) || size >= 0) g_signal_emit_by_name (data->widget, "drag-data-received", data->drop, &sdata); } } else { g_signal_emit_by_name (data->widget, "drag-data-received", data->drop, &sdata); } if (site && site->flags & GTK_DEST_DEFAULT_DROP) { GdkDragAction action = site->actions & gdk_drop_get_actions (data->drop); if (size == 0) action = 0; if (!gdk_drag_action_is_unique (action)) { if (action & GDK_ACTION_COPY) action = GDK_ACTION_COPY; else if (action & GDK_ACTION_MOVE) action = GDK_ACTION_MOVE; } gdk_drop_finish (data->drop, action); } g_object_unref (data->widget); g_object_unref (data->drop); g_slice_free (GtkDragGetData, data); } static void gtk_drag_get_data_got_data (GObject *source, GAsyncResult *result, gpointer data) { gssize written; written = g_output_stream_splice_finish (G_OUTPUT_STREAM (source), result, NULL); if (written < 0) { gtk_drag_get_data_finish (data, NULL, 0); } else { gtk_drag_get_data_finish (data, g_memory_output_stream_get_data (G_MEMORY_OUTPUT_STREAM (source)), g_memory_output_stream_get_data_size (G_MEMORY_OUTPUT_STREAM (source))); } } static void gtk_drag_get_data_got_stream (GObject *source, GAsyncResult *result, gpointer user_data) { GtkDragGetData *data = user_data; GInputStream *input_stream; GOutputStream *output_stream; input_stream = gdk_drop_read_finish (GDK_DROP (source), result, &data->mime_type, NULL); if (input_stream == NULL) { gtk_drag_get_data_finish (data, NULL, 0); return; } output_stream = g_memory_output_stream_new_resizable (); g_output_stream_splice_async (output_stream, input_stream, G_OUTPUT_STREAM_SPLICE_CLOSE_SOURCE | G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET, G_PRIORITY_DEFAULT, NULL, gtk_drag_get_data_got_data, data); g_object_unref (output_stream); g_object_unref (input_stream); } /** * gtk_drag_get_data: (method) * @widget: the widget that will receive the * #GtkWidget::drag-data-received signal * @drop: the #GdkDrop * @target: the target (form of the data) to retrieve * * Gets the data associated with a drag. When the data * is received or the retrieval fails, GTK+ will emit a * #GtkWidget::drag-data-received signal. Failure of the retrieval * is indicated by the length field of the @selection_data * signal parameter being negative. However, when gtk_drag_get_data() * is called implicitely because the %GTK_DEST_DEFAULT_DROP was set, * then the widget will not receive notification of failed * drops. */ void gtk_drag_get_data (GtkWidget *widget, GdkDrop *drop, GdkAtom target) { GtkDragGetData *data; g_return_if_fail (GTK_IS_WIDGET (widget)); g_return_if_fail (GDK_IS_DROP (drop)); data = g_slice_new0 (GtkDragGetData); data->widget = g_object_ref (widget); data->drop = g_object_ref (drop); data->mime_type = target; gdk_drop_read_async (drop, (const gchar *[2]) { target, NULL }, G_PRIORITY_DEFAULT, NULL, gtk_drag_get_data_got_stream, data); } /** * gtk_drag_get_source_widget: * @drag: a drag context * * Determines the source widget for a drag. * * Returns: (nullable) (transfer none): if the drag is occurring * within a single application, a pointer to the source widget. * Otherwise, %NULL. */ GtkWidget * gtk_drag_get_source_widget (GdkDrag *drag) { GtkDragSourceInfo *info; g_return_val_if_fail (GDK_IS_DRAG (drag), NULL); info = gtk_drag_get_source_info (drag, FALSE); if (info == NULL) return NULL; return info->widget; } /** * gtk_drag_highlight: (method) * @widget: a widget to highlight * * Highlights a widget as a currently hovered drop target. * To end the highlight, call gtk_drag_unhighlight(). * GTK+ calls this automatically if %GTK_DEST_DEFAULT_HIGHLIGHT is set. */ void gtk_drag_highlight (GtkWidget *widget) { g_return_if_fail (GTK_IS_WIDGET (widget)); gtk_widget_set_state_flags (widget, GTK_STATE_FLAG_DROP_ACTIVE, FALSE); } /** * gtk_drag_unhighlight: (method) * @widget: a widget to remove the highlight from * * Removes a highlight set by gtk_drag_highlight() from * a widget. */ void gtk_drag_unhighlight (GtkWidget *widget) { g_return_if_fail (GTK_IS_WIDGET (widget)); gtk_widget_unset_state_flags (widget, GTK_STATE_FLAG_DROP_ACTIVE); } /* * _gtk_drag_dest_handle_event: * @toplevel: Toplevel widget that received the event * @event: the event to handle * * Called from widget event handling code on Drag events * for destinations. */ void _gtk_drag_dest_handle_event (GtkWidget *toplevel, GdkEvent *event) { GtkDragDestInfo *info; GdkDrop *drop; guint32 time; GdkEventType event_type; g_return_if_fail (toplevel != NULL); g_return_if_fail (event != NULL); event_type = gdk_event_get_event_type (event); drop = gdk_event_get_drop (event); time = gdk_event_get_time (event); info = gtk_drag_get_dest_info (drop, TRUE); /* Find the widget for the event */ switch ((guint) event_type) { case GDK_DRAG_ENTER: break; case GDK_DRAG_LEAVE: if (info->widget) { gtk_drag_dest_leave (info->widget, drop, time); gtk_drag_dest_set_widget (info, NULL); } break; case GDK_DRAG_MOTION: case GDK_DROP_START: { double x, y; gboolean found; if (event_type == GDK_DROP_START) { /* We send a leave here so that the widget unhighlights * properly. */ if (info->widget) { gtk_drag_dest_leave (info->widget, drop, time); gtk_drag_dest_set_widget (info, NULL); } } gdk_event_get_coords (event, &x, &y); found = gtk_drop_find_widget (toplevel, drop, info, x, y, time, (event_type == GDK_DRAG_MOTION) ? gtk_drag_dest_motion : gtk_drag_dest_drop); if (info->widget && !found) { gtk_drag_dest_leave (info->widget, drop, time); gtk_drag_dest_set_widget (info, NULL); } /* Send a reply. */ if (!found) gdk_drop_status (drop, 0); } break; default: g_assert_not_reached (); } } static gboolean gtk_drop_find_widget (GtkWidget *event_widget, GdkDrop *drop, GtkDragDestInfo *info, gint x, gint y, guint32 time, GtkDragDestCallback callback) { GtkWidget *widget; if (!gtk_widget_get_mapped (event_widget) || !gtk_widget_get_sensitive (event_widget)) return FALSE; widget = gtk_widget_pick (event_widget, x, y, GTK_PICK_DEFAULT); if (!widget) return FALSE; gtk_widget_translate_coordinates (event_widget, widget, x, y, &x, &y); while (widget) { GtkWidget *parent; GList *hierarchy = NULL; gboolean found = FALSE; if (!gtk_widget_get_mapped (widget)) return FALSE; if (gtk_widget_get_state_flags (widget) & GTK_STATE_FLAG_INSENSITIVE) { widget = gtk_widget_get_parent (widget); continue; } /* need to reference the entire hierarchy temporarily in case the * ::drag-motion/::drag-drop callbacks change the widget hierarchy. */ for (parent = widget; parent; parent = gtk_widget_get_parent (parent)) { hierarchy = g_list_prepend (hierarchy, g_object_ref (parent)); } /* If the current widget is registered as a drop site, check to * emit "drag-motion" to check if we are actually in a drop * site. */ if (g_object_get_data (G_OBJECT (widget), "gtk-drag-dest")) { found = callback (widget, drop, x, y, time); /* If so, send a "drag-leave" to the last widget */ if (found && info->widget != widget) { if (info->widget) gtk_drag_dest_leave (info->widget, drop, time); gtk_drag_dest_set_widget (info, widget); } } if (!found) { /* Get the parent before unreffing the hierarchy because * invoking the callback might have destroyed the widget */ parent = gtk_widget_get_parent (widget); /* The parent might be going away when unreffing the * hierarchy, so also protect againt that */ if (parent) g_object_add_weak_pointer (G_OBJECT (parent), (gpointer *) &parent); } g_list_free_full (hierarchy, g_object_unref); if (found) return TRUE; if (parent) g_object_remove_weak_pointer (G_OBJECT (parent), (gpointer *) &parent); else return FALSE; if (!gtk_widget_translate_coordinates (widget, parent, x, y, &x, &y)) return FALSE; widget = parent; } return FALSE; } static void gtk_drag_dest_set_widget (GtkDragDestInfo *info, GtkWidget *widget) { if (info->widget) g_object_remove_weak_pointer (G_OBJECT (info->widget), (gpointer *) &info->widget); info->widget = widget; if (info->widget) g_object_add_weak_pointer (G_OBJECT (info->widget), (gpointer *) &info->widget); } static void gtk_drag_dest_info_destroy (gpointer data) { GtkDragDestInfo *info = (GtkDragDestInfo *)data; gtk_drag_dest_set_widget (info, NULL); g_slice_free (GtkDragDestInfo, data); } static GtkDragDestInfo * gtk_drag_get_dest_info (GdkDrop *drop, gboolean create) { GtkDragDestInfo *info; static GQuark info_quark = 0; if (!info_quark) info_quark = g_quark_from_static_string ("gtk-dest-info"); info = g_object_get_qdata (G_OBJECT (drop), info_quark); if (!info && create) { info = g_slice_new0 (GtkDragDestInfo); info->drop = drop; g_object_set_qdata_full (G_OBJECT (drop), info_quark, info, gtk_drag_dest_info_destroy); } return info; } static GQuark dest_info_quark = 0; static GtkDragSourceInfo * gtk_drag_get_source_info (GdkDrag *drag, gboolean create) { GtkDragSourceInfo *info; if (!dest_info_quark) dest_info_quark = g_quark_from_static_string ("gtk-source-info"); info = g_object_get_qdata (G_OBJECT (drag), dest_info_quark); if (!info && create) { info = g_new0 (GtkDragSourceInfo, 1); info->drag = drag; g_object_set_qdata (G_OBJECT (drag), dest_info_quark, info); } return info; } static void gtk_drag_clear_source_info (GdkDrag *drag) { g_object_set_qdata (G_OBJECT (drag), dest_info_quark, NULL); } /* * Default drag handlers */ static void gtk_drag_dest_leave (GtkWidget *widget, GdkDrop *drop, guint time) { GtkDragDestSite *site; site = g_object_get_data (G_OBJECT (widget), "gtk-drag-dest"); g_return_if_fail (site != NULL); if ((site->flags & GTK_DEST_DEFAULT_HIGHLIGHT) && site->have_drag) gtk_drag_unhighlight (widget); if (!(site->flags & GTK_DEST_DEFAULT_MOTION) || site->have_drag || site->track_motion) g_signal_emit_by_name (widget, "drag-leave", drop, time); site->have_drag = FALSE; } static gboolean gtk_drag_dest_motion (GtkWidget *widget, GdkDrop *drop, gint x, gint y, guint time) { GtkDragDestSite *site; gboolean retval; site = g_object_get_data (G_OBJECT (widget), "gtk-drag-dest"); g_return_val_if_fail (site != NULL, FALSE); if (site->track_motion || site->flags & GTK_DEST_DEFAULT_MOTION) { GdkDragAction actions; actions = gdk_drop_get_actions (drop); if ((actions & site->actions) == 0) actions = 0; if (actions && gtk_drag_dest_find_target (widget, drop, NULL)) { if (!site->have_drag) { site->have_drag = TRUE; if (site->flags & GTK_DEST_DEFAULT_HIGHLIGHT) gtk_drag_highlight (widget); } gdk_drop_status (drop, site->actions); } else { gdk_drop_status (drop, 0); if (!site->track_motion) return TRUE; } } g_signal_emit_by_name (widget, "drag-motion", drop, x, y, &retval); return (site->flags & GTK_DEST_DEFAULT_MOTION) ? TRUE : retval; } static gboolean gtk_drag_dest_drop (GtkWidget *widget, GdkDrop *drop, gint x, gint y, guint time) { GtkDragDestSite *site; GtkDragDestInfo *info; gboolean retval; site = g_object_get_data (G_OBJECT (widget), "gtk-drag-dest"); g_return_val_if_fail (site != NULL, FALSE); info = gtk_drag_get_dest_info (drop, FALSE); g_return_val_if_fail (info != NULL, FALSE); if (site->flags & GTK_DEST_DEFAULT_DROP) { GdkAtom target = gtk_drag_dest_find_target (widget, drop, NULL); if (target == NULL) { gdk_drop_finish (drop, 0); return TRUE; } else gtk_drag_get_data (widget, drop, target); } g_signal_emit_by_name (widget, "drag-drop", drop, x, y, &retval); return (site->flags & GTK_DEST_DEFAULT_DROP) ? TRUE : retval; } /*************** * Source side * ***************/ #define GTK_TYPE_DRAG_CONTENT (gtk_drag_content_get_type ()) #define GTK_DRAG_CONTENT(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GTK_TYPE_DRAG_CONTENT, GtkDragContent)) #define GTK_IS_DRAG_CONTENT(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GTK_TYPE_DRAG_CONTENT)) #define GTK_DRAG_CONTENT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GTK_TYPE_DRAG_CONTENT, GtkDragContentClass)) #define GTK_IS_DRAG_CONTENT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GTK_TYPE_DRAG_CONTENT)) #define GTK_DRAG_CONTENT_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GTK_TYPE_DRAG_CONTENT, GtkDragContentClass)) typedef struct _GtkDragContent GtkDragContent; typedef struct _GtkDragContentClass GtkDragContentClass; struct _GtkDragContent { GdkContentProvider parent; GtkWidget *widget; GdkDrag *drag; GdkContentFormats *formats; guint32 time; }; struct _GtkDragContentClass { GdkContentProviderClass parent_class; }; GType gtk_drag_content_get_type (void) G_GNUC_CONST; G_DEFINE_TYPE (GtkDragContent, gtk_drag_content, GDK_TYPE_CONTENT_PROVIDER) static GdkContentFormats * gtk_drag_content_ref_formats (GdkContentProvider *provider) { GtkDragContent *content = GTK_DRAG_CONTENT (provider); return gdk_content_formats_ref (content->formats); } static void gtk_drag_content_write_mime_type_done (GObject *stream, GAsyncResult *result, gpointer task) { GError *error = NULL; if (!g_output_stream_write_all_finish (G_OUTPUT_STREAM (stream), result, NULL, &error)) { g_task_return_error (task, error); } else { g_task_return_boolean (task, TRUE); } g_object_unref (task); } static void gtk_drag_content_write_mime_type_async (GdkContentProvider *provider, const char *mime_type, GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GtkDragContent *content = GTK_DRAG_CONTENT (provider); GtkSelectionData sdata = { 0, }; GTask *task; task = g_task_new (content, cancellable, callback, user_data); g_task_set_priority (task, io_priority); g_task_set_source_tag (task, gtk_drag_content_write_mime_type_async); sdata.target = g_intern_string (mime_type); sdata.length = -1; sdata.display = gtk_widget_get_display (content->widget); g_signal_emit_by_name (content->widget, "drag-data-get", content->drag, &sdata); if (sdata.length == -1) { g_task_return_new_error (task, G_IO_ERROR, G_IO_ERROR_FAILED, _("Cannot provide contents as “%s”"), mime_type); g_object_unref (task); return; } g_task_set_task_data (task, sdata.data, g_free); g_output_stream_write_all_async (stream, sdata.data, sdata.length, io_priority, cancellable, gtk_drag_content_write_mime_type_done, task); } static gboolean gtk_drag_content_write_mime_type_finish (GdkContentProvider *provider, GAsyncResult *result, GError **error) { g_return_val_if_fail (g_task_is_valid (result, provider), FALSE); g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_drag_content_write_mime_type_async, FALSE); return g_task_propagate_boolean (G_TASK (result), error); } static void gtk_drag_content_finalize (GObject *object) { GtkDragContent *content = GTK_DRAG_CONTENT (object); g_clear_object (&content->widget); g_clear_pointer (&content->formats, gdk_content_formats_unref); G_OBJECT_CLASS (gtk_drag_content_parent_class)->finalize (object); } static void gtk_drag_content_class_init (GtkDragContentClass *class) { GdkContentProviderClass *provider_class = GDK_CONTENT_PROVIDER_CLASS (class); GObjectClass *object_class = G_OBJECT_CLASS (class); object_class->finalize = gtk_drag_content_finalize; provider_class->ref_formats = gtk_drag_content_ref_formats; provider_class->write_mime_type_async = gtk_drag_content_write_mime_type_async; provider_class->write_mime_type_finish = gtk_drag_content_write_mime_type_finish; } static void gtk_drag_content_init (GtkDragContent *content) { } /* Like gtk_drag_begin(), but also takes a GtkImageDefinition * so that we can set the icon from the source site information */ GdkDrag * gtk_drag_begin_internal (GtkWidget *widget, GdkDevice *device, GtkImageDefinition *icon, GdkContentFormats *target_list, GdkDragAction actions, int x, int y) { GtkDragSourceInfo *info; GtkNative *native; GdkDrag *drag; double px, py; int dx, dy; GtkDragContent *content; if (gdk_device_get_source (device) == GDK_SOURCE_KEYBOARD) device = gdk_device_get_associated_device (device); native = gtk_widget_get_native (widget); gtk_widget_translate_coordinates (widget, GTK_WIDGET (native), x, y, &x, &y); gdk_surface_get_device_position (gtk_native_get_surface (native), device, &px, &py, NULL); dx = round (px) - x; dy = round (py) - y; content = g_object_new (GTK_TYPE_DRAG_CONTENT, NULL); content->widget = g_object_ref (widget); content->formats = gdk_content_formats_ref (target_list); drag = gdk_drag_begin (gtk_native_get_surface (native), device, GDK_CONTENT_PROVIDER (content), actions, dx, dy); if (drag == NULL) { g_object_unref (content); return NULL; } content->drag = drag; g_object_unref (content); info = gtk_drag_get_source_info (drag, TRUE); g_object_set_data (G_OBJECT (widget), I_("gtk-info"), info); info->widget = g_object_ref (widget); info->target_list = target_list; gdk_content_formats_ref (target_list); info->icon_window = NULL; info->icon_widget = NULL; info->destroy_icon = FALSE; gtk_widget_reset_controllers (widget); g_signal_emit_by_name (widget, "drag-begin", info->drag); /* Ensure that we have an icon before we start the drag; the * application may have set one in ::drag_begin, or it may * not have set one. */ if (!info->icon_widget) { if (icon) { set_icon_helper (info->drag, icon, 0, 0); } else { icon = gtk_image_definition_new_icon_name ("text-x-generic"); set_icon_helper (info->drag, icon, 0, 0); gtk_image_definition_unref (icon); } } g_signal_connect (drag, "drop-performed", G_CALLBACK (gtk_drag_drop_performed_cb), info); g_signal_connect (drag, "dnd-finished", G_CALLBACK (gtk_drag_dnd_finished_cb), info); g_signal_connect (drag, "cancel", G_CALLBACK (gtk_drag_cancel_cb), info); return info->drag; } /** * gtk_drag_begin: (method) * @widget: the source widget * @device: (nullable): the device that starts the drag or %NULL to use the default pointer * @targets: The targets (data formats) in which the source can provide the data * @actions: A bitmask of the allowed drag actions for this drag * @x: The initial x coordinate to start dragging from, in the coordinate space of @widget. * @y: The initial y coordinate to start dragging from, in the coordinate space of @widget. * * Initiates a drag on the source side. The function only needs to be used * when the application is starting drags itself, and is not needed when * gtk_drag_source_set() is used. * * Returns: (transfer none): the context for this drag */ GdkDrag * gtk_drag_begin (GtkWidget *widget, GdkDevice *device, GdkContentFormats *targets, GdkDragAction actions, gint x, gint y) { g_return_val_if_fail (GTK_IS_WIDGET (widget), NULL); g_return_val_if_fail (device == NULL || GDK_IS_DEVICE (device), NULL); g_return_val_if_fail (gtk_widget_get_realized (widget), NULL); g_return_val_if_fail (targets != NULL, NULL); if (device == NULL) { GdkSeat *seat; seat = gdk_display_get_default_seat (gtk_widget_get_display (widget)); device = gdk_seat_get_pointer (seat); } return gtk_drag_begin_internal (widget, device, NULL, targets, actions, x, y); } static void icon_widget_destroyed (GtkWidget *widget, GtkDragSourceInfo *info) { g_clear_object (&info->icon_widget); } static void gtk_drag_set_icon_widget_internal (GdkDrag *drag, GtkWidget *widget, gint hot_x, gint hot_y, gboolean destroy_on_release) { GtkDragSourceInfo *info; g_return_if_fail (!GTK_IS_WINDOW (widget)); info = gtk_drag_get_source_info (drag, FALSE); if (info == NULL) { if (destroy_on_release) gtk_widget_destroy (widget); return; } gtk_drag_remove_icon (info); if (widget) g_object_ref (widget); info->icon_widget = widget; info->destroy_icon = destroy_on_release; if (!widget) return; g_signal_connect (widget, "destroy", G_CALLBACK (icon_widget_destroyed), info); gdk_drag_set_hotspot (drag, hot_x, hot_y); if (!info->icon_window) { info->icon_window = gtk_drag_icon_new (); g_object_ref_sink (info->icon_window); gtk_widget_set_size_request (info->icon_window, 24, 24); gtk_drag_icon_set_surface (GTK_DRAG_ICON (info->icon_window), gdk_drag_get_drag_surface (drag)); gtk_widget_show (info->icon_window); } gtk_drag_icon_set_widget (GTK_DRAG_ICON (info->icon_window), widget); } /** * gtk_drag_set_icon_widget: * @drag: the context for a drag * @widget: a widget to use as an icon * @hot_x: the X offset within @widget of the hotspot * @hot_y: the Y offset within @widget of the hotspot * * Changes the icon for drag operation to a given widget. * GTK+ will not destroy the widget, so if you don’t want * it to persist, you should connect to the “drag-end” * signal and destroy it yourself. */ void gtk_drag_set_icon_widget (GdkDrag *drag, GtkWidget *widget, gint hot_x, gint hot_y) { g_return_if_fail (GDK_IS_DRAG (drag)); g_return_if_fail (GTK_IS_WIDGET (widget)); gtk_drag_set_icon_widget_internal (drag, widget, hot_x, hot_y, FALSE); } static void set_icon_helper (GdkDrag *drag, GtkImageDefinition *def, gint hot_x, gint hot_y) { GtkWidget *widget; widget = gtk_image_new (); gtk_style_context_add_class (gtk_widget_get_style_context (widget), "drag-icon"); gtk_image_set_from_definition (GTK_IMAGE (widget), def); gtk_drag_set_icon_widget_internal (drag, widget, hot_x, hot_y, TRUE); } void gtk_drag_set_icon_definition (GdkDrag *drag, GtkImageDefinition *def, gint hot_x, gint hot_y) { g_return_if_fail (GDK_IS_DRAG (drag)); g_return_if_fail (def != NULL); set_icon_helper (drag, def, hot_x, hot_y); } /** * gtk_drag_set_icon_paintable: * @drag: the context for a drag * @paintable: the #GdkPaintable to use as icon * @hot_x: the X offset of the hotspot within the icon * @hot_y: the Y offset of the hotspot within the icon * * Sets @paintable as the icon for a given drag. GTK+ retains * references for the arguments, and will release them when * they are no longer needed. * * To position the @paintable relative to the mouse, its top * left will be positioned @hot_x, @hot_y pixels from the * mouse cursor. */ void gtk_drag_set_icon_paintable (GdkDrag *drag, GdkPaintable *paintable, int hot_x, int hot_y) { GtkWidget *widget; g_return_if_fail (GDK_IS_DRAG (drag)); g_return_if_fail (GDK_IS_PAINTABLE (paintable)); widget = gtk_picture_new_for_paintable (paintable); gtk_picture_set_can_shrink (GTK_PICTURE (widget), FALSE); gtk_drag_set_icon_widget_internal (drag, widget, hot_x, hot_y, TRUE); } /** * gtk_drag_set_icon_name: * @drag: the context for a drag * @icon_name: name of icon to use * @hot_x: the X offset of the hotspot within the icon * @hot_y: the Y offset of the hotspot within the icon * * Sets the icon for a given drag from a named themed icon. See * the docs for #GtkIconTheme for more details. Note that the * size of the icon depends on the icon theme (the icon is * loaded at the symbolic size #GTK_ICON_SIZE_DND), thus * @hot_x and @hot_y have to be used with care. */ void gtk_drag_set_icon_name (GdkDrag *drag, const gchar *icon_name, gint hot_x, gint hot_y) { GtkImageDefinition *def; g_return_if_fail (GDK_IS_DRAG (drag)); g_return_if_fail (icon_name != NULL && icon_name[0] != '\0'); def = gtk_image_definition_new_icon_name (icon_name); set_icon_helper (drag, def, hot_x, hot_y); gtk_image_definition_unref (def); } /** * gtk_drag_set_icon_gicon: * @drag: the context for a drag * @icon: a #GIcon * @hot_x: the X offset of the hotspot within the icon * @hot_y: the Y offset of the hotspot within the icon * * Sets the icon for a given drag from the given @icon. * See the documentation for gtk_drag_set_icon_name() * for more details about using icons in drag and drop. */ void gtk_drag_set_icon_gicon (GdkDrag *drag, GIcon *icon, gint hot_x, gint hot_y) { GtkImageDefinition *def; g_return_if_fail (GDK_IS_DRAG (drag)); g_return_if_fail (icon != NULL); def = gtk_image_definition_new_gicon (icon); set_icon_helper (drag, def, hot_x, hot_y); gtk_image_definition_unref (def); } /** * gtk_drag_set_icon_default: * @drag: the context for a drag * * Sets the icon for a particular drag to the default * icon. */ void gtk_drag_set_icon_default (GdkDrag *drag) { g_return_if_fail (GDK_IS_DRAG (drag)); gtk_drag_set_icon_name (drag, "text-x-generic", -2, -2); } /* Clean up from the drag, and display snapback, if necessary. */ static void gtk_drag_drop_finished (GtkDragSourceInfo *info, GtkDragResult result) { gboolean success; success = (result == GTK_DRAG_RESULT_SUCCESS); if (!success) g_signal_emit_by_name (info->widget, "drag-failed", info->drag, result, &success); gdk_drag_drop_done (info->drag, success); gtk_drag_source_info_destroy (info); } static void gtk_drag_drop (GtkDragSourceInfo *info) { if (info->icon_window) gtk_widget_hide (info->icon_window); info->drop_timeout = g_timeout_add (DROP_ABORT_TIME, gtk_drag_abort_timeout, info); g_source_set_name_by_id (info->drop_timeout, "[gtk] gtk_drag_abort_timeout"); } /* * Source side callbacks. */ static void gtk_drag_remove_icon (GtkDragSourceInfo *info) { if (info->icon_widget) { GtkWidget *widget; widget = info->icon_widget; info->icon_widget = NULL; g_signal_handlers_disconnect_by_func (widget, icon_widget_destroyed, info); gtk_widget_hide (widget); gtk_widget_set_opacity (widget, 1.0); if (info->destroy_icon) gtk_widget_destroy (widget); else gtk_drag_icon_set_widget (GTK_DRAG_ICON (info->icon_window), NULL); g_object_unref (widget); } } static void gtk_drag_source_info_free (GtkDragSourceInfo *info) { gtk_drag_remove_icon (info); g_object_unref (info->icon_window); g_free (info); } static void gtk_drag_source_info_destroy (GtkDragSourceInfo *info) { g_signal_handlers_disconnect_by_func (info->drag, gtk_drag_drop_performed_cb, info); g_signal_handlers_disconnect_by_func (info->drag, gtk_drag_dnd_finished_cb, info); g_signal_handlers_disconnect_by_func (info->drag, gtk_drag_cancel_cb, info); g_signal_emit_by_name (info->widget, "drag-end", info->drag); g_object_set_data (G_OBJECT (info->widget), I_("gtk-info"), NULL); g_clear_object (&info->widget); gdk_content_formats_unref (info->target_list); if (info->drop_timeout) g_source_remove (info->drop_timeout); /* keep the icon_window alive until the (possible) drag cancel animation is done */ g_object_set_data_full (G_OBJECT (info->drag), "former-gtk-source-info", info, (GDestroyNotify)gtk_drag_source_info_free); gtk_drag_clear_source_info (info->drag); g_object_unref (info->drag); } /* Called on cancellation of a drag, either by the user * or programmatically. */ static void gtk_drag_cancel_internal (GtkDragSourceInfo *info, GtkDragResult result) { gtk_drag_drop_finished (info, result); } static void gtk_drag_drop_performed_cb (GdkDrag *drag, GtkDragSourceInfo *info) { gtk_drag_drop (info); } static void gtk_drag_cancel_cb (GdkDrag *drag, GdkDragCancelReason reason, GtkDragSourceInfo *info) { GtkDragResult result; switch (reason) { case GDK_DRAG_CANCEL_NO_TARGET: result = GTK_DRAG_RESULT_NO_TARGET; break; case GDK_DRAG_CANCEL_USER_CANCELLED: result = GTK_DRAG_RESULT_USER_CANCELLED; break; case GDK_DRAG_CANCEL_ERROR: default: result = GTK_DRAG_RESULT_ERROR; break; } gtk_drag_cancel_internal (info, result); } static void gtk_drag_dnd_finished_cb (GdkDrag *drag, GtkDragSourceInfo *info) { if (gdk_drag_get_selected_action (drag) == GDK_ACTION_MOVE) { g_signal_emit_by_name (info->widget, "drag-data-delete", drag); } gtk_drag_source_info_destroy (info); } static gboolean gtk_drag_abort_timeout (gpointer data) { GtkDragSourceInfo *info = data; info->drop_timeout = 0; gtk_drag_drop_finished (info, GTK_DRAG_RESULT_TIMEOUT_EXPIRED); return G_SOURCE_REMOVE; } /** * gtk_drag_check_threshold: (method) * @widget: a #GtkWidget * @start_x: X coordinate of start of drag * @start_y: Y coordinate of start of drag * @current_x: current X coordinate * @current_y: current Y coordinate * * Checks to see if a mouse drag starting at (@start_x, @start_y) and ending * at (@current_x, @current_y) has passed the GTK+ drag threshold, and thus * should trigger the beginning of a drag-and-drop operation. * * Returns: %TRUE if the drag threshold has been passed. */ gboolean gtk_drag_check_threshold (GtkWidget *widget, gint start_x, gint start_y, gint current_x, gint current_y) { gint drag_threshold; g_return_val_if_fail (GTK_IS_WIDGET (widget), FALSE); drag_threshold = gtk_settings_get_dnd_drag_threshold (gtk_widget_get_settings (widget)); return (ABS (current_x - start_x) > drag_threshold || ABS (current_y - start_y) > drag_threshold); } /** * gtk_drag_cancel: * @drag: a drag context, as e.g. returned by gtk_drag_begin() * * Cancels an ongoing drag operation on the source side. * * If you want to be able to cancel a drag operation in this way, * you need to keep a pointer to the drag context, either from an * explicit call to gtk_drag_begin(), or by connecting to * #GtkWidget::drag-begin. * * If @context does not refer to an ongoing drag operation, this * function does nothing. * * If a drag is cancelled in this way, the @result argument of * #GtkWidget::drag-failed is set to @GTK_DRAG_RESULT_ERROR. */ void gtk_drag_cancel (GdkDrag *drag) { GtkDragSourceInfo *info; g_return_if_fail (GDK_IS_DRAG (drag)); info = gtk_drag_get_source_info (drag, FALSE); if (info != NULL) gtk_drag_cancel_internal (info, GTK_DRAG_RESULT_ERROR); }