1 /* eggtreemultidnd.c
2 * Copyright (C) 2001 Red Hat, Inc.
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 #include <string.h>
21 #include <gtk/gtk.h>
22 #include "eggtreemultidnd.h"
23
24 #define EGG_TREE_MULTI_DND_STRING "EggTreeMultiDndString"
25
26 typedef struct
27 {
28 guint pressed_button;
29 gint x;
30 gint y;
31 gulong motion_notify_handler;
32 gulong button_release_handler;
33 gulong drag_data_get_handler;
34 GSList *event_list;
35 } EggTreeMultiDndData;
36
37 /* CUT-N-PASTE from gtktreeview.c */
38 typedef struct _TreeViewDragInfo TreeViewDragInfo;
39 struct _TreeViewDragInfo
40 {
41 GdkModifierType start_button_mask;
42
43 /* This has been unused since 2.14.x */
44 GtkTargetList *unused_source_target_list;
45 GdkDragAction source_actions;
46
47 GtkTargetList *dest_target_list;
48
49 guint source_set : 1;
50 guint dest_set : 1;
51 };
52
53
54 GType
egg_tree_multi_drag_source_get_type(void)55 egg_tree_multi_drag_source_get_type (void)
56 {
57 static GType our_type = 0;
58
59 if (!our_type)
60 {
61 static const GTypeInfo our_info =
62 {
63 sizeof (EggTreeMultiDragSourceIface), /* class_size */
64 NULL, /* base_init */
65 NULL, /* base_finalize */
66 NULL,
67 NULL, /* class_finalize */
68 NULL, /* class_data */
69 0,
70 0, /* n_preallocs */
71 NULL
72 };
73
74 our_type = g_type_register_static (G_TYPE_INTERFACE, "EggTreeMultiDragSource", &our_info, 0);
75 }
76
77 return our_type;
78 }
79
80
81 /**
82 * egg_tree_multi_drag_source_row_draggable:
83 * @drag_source: a #EggTreeMultiDragSource
84 * @path: row on which user is initiating a drag
85 *
86 * Asks the #EggTreeMultiDragSource whether a particular row can be used as
87 * the source of a DND operation. If the source doesn't implement
88 * this interface, the row is assumed draggable.
89 *
90 * Return value: %TRUE if the row can be dragged
91 **/
92 gboolean
egg_tree_multi_drag_source_row_draggable(EggTreeMultiDragSource * drag_source,GList * path_list)93 egg_tree_multi_drag_source_row_draggable (EggTreeMultiDragSource *drag_source,
94 GList *path_list)
95 {
96 EggTreeMultiDragSourceIface *iface = EGG_TREE_MULTI_DRAG_SOURCE_GET_IFACE (drag_source);
97
98 g_return_val_if_fail (EGG_IS_TREE_MULTI_DRAG_SOURCE (drag_source), FALSE);
99 g_return_val_if_fail (iface->row_draggable != NULL, FALSE);
100 g_return_val_if_fail (path_list != NULL, FALSE);
101
102 if (iface->row_draggable)
103 return (* iface->row_draggable) (drag_source, path_list);
104 else
105 return TRUE;
106 }
107
108
109 /**
110 * egg_tree_multi_drag_source_drag_data_delete:
111 * @drag_source: a #EggTreeMultiDragSource
112 * @path: row that was being dragged
113 *
114 * Asks the #EggTreeMultiDragSource to delete the row at @path, because
115 * it was moved somewhere else via drag-and-drop. Returns %FALSE
116 * if the deletion fails because @path no longer exists, or for
117 * some model-specific reason. Should robustly handle a @path no
118 * longer found in the model!
119 *
120 * Return value: %TRUE if the row was successfully deleted
121 **/
122 gboolean
egg_tree_multi_drag_source_drag_data_delete(EggTreeMultiDragSource * drag_source,GList * path_list)123 egg_tree_multi_drag_source_drag_data_delete (EggTreeMultiDragSource *drag_source,
124 GList *path_list)
125 {
126 EggTreeMultiDragSourceIface *iface = EGG_TREE_MULTI_DRAG_SOURCE_GET_IFACE (drag_source);
127
128 g_return_val_if_fail (EGG_IS_TREE_MULTI_DRAG_SOURCE (drag_source), FALSE);
129 g_return_val_if_fail (iface->drag_data_delete != NULL, FALSE);
130 g_return_val_if_fail (path_list != NULL, FALSE);
131
132 return (* iface->drag_data_delete) (drag_source, path_list);
133 }
134
135 /**
136 * egg_tree_multi_drag_source_drag_data_get:
137 * @drag_source: a #EggTreeMultiDragSource
138 * @path: row that was dragged
139 * @selection_data: a #EggSelectionData to fill with data from the dragged row
140 *
141 * Asks the #EggTreeMultiDragSource to fill in @selection_data with a
142 * representation of the row at @path. @selection_data->target gives
143 * the required type of the data. Should robustly handle a @path no
144 * longer found in the model!
145 *
146 * Return value: %TRUE if data of the required type was provided
147 **/
148 gboolean
egg_tree_multi_drag_source_drag_data_get(EggTreeMultiDragSource * drag_source,GList * path_list,GtkSelectionData * selection_data)149 egg_tree_multi_drag_source_drag_data_get (EggTreeMultiDragSource *drag_source,
150 GList *path_list,
151 GtkSelectionData *selection_data)
152 {
153 EggTreeMultiDragSourceIface *iface = EGG_TREE_MULTI_DRAG_SOURCE_GET_IFACE (drag_source);
154
155 g_return_val_if_fail (EGG_IS_TREE_MULTI_DRAG_SOURCE (drag_source), FALSE);
156 g_return_val_if_fail (iface->drag_data_get != NULL, FALSE);
157 g_return_val_if_fail (path_list != NULL, FALSE);
158 g_return_val_if_fail (selection_data != NULL, FALSE);
159
160 return (* iface->drag_data_get) (drag_source, path_list, selection_data);
161 }
162
163 static void
stop_drag_check(GtkWidget * widget)164 stop_drag_check (GtkWidget *widget)
165 {
166 EggTreeMultiDndData *priv_data;
167 GSList *l;
168
169 priv_data = g_object_get_data (G_OBJECT (widget), EGG_TREE_MULTI_DND_STRING);
170
171 for (l = priv_data->event_list; l != NULL; l = l->next)
172 gdk_event_free (l->data);
173
174 g_slist_free (priv_data->event_list);
175 priv_data->event_list = NULL;
176 }
177
178 static gboolean
egg_tree_multi_drag_button_release_event(GtkWidget * widget,GdkEventButton * event,gpointer data)179 egg_tree_multi_drag_button_release_event (GtkWidget *widget,
180 GdkEventButton *event,
181 gpointer data)
182 {
183 EggTreeMultiDndData *priv_data;
184 GSList *l;
185
186 priv_data = g_object_get_data (G_OBJECT (widget), EGG_TREE_MULTI_DND_STRING);
187
188 /* disconnect before sending all queued events to avoid a warning with
189 * GtkFileChooserDialog and double click. */
190 if (priv_data->motion_notify_handler) {
191 g_signal_handler_disconnect (widget, priv_data->motion_notify_handler);
192 priv_data->motion_notify_handler = 0;
193 }
194 if (priv_data->button_release_handler) {
195 g_signal_handler_disconnect (widget, priv_data->button_release_handler);
196 priv_data->button_release_handler = 0;
197 }
198
199 for (l = priv_data->event_list; l != NULL && gtk_widget_get_realized (widget); l = l->next)
200 gtk_propagate_event (widget, l->data);
201
202 stop_drag_check (widget);
203
204 return FALSE;
205 }
206
207 static void
selection_foreach(GtkTreeModel * model,GtkTreePath * path,GtkTreeIter * iter,gpointer data)208 selection_foreach (GtkTreeModel *model,
209 GtkTreePath *path,
210 GtkTreeIter *iter,
211 gpointer data)
212 {
213 GList **list_ptr;
214
215 list_ptr = (GList **) data;
216
217 *list_ptr = g_list_prepend (*list_ptr, gtk_tree_row_reference_new (model, path));
218 }
219
220 static void
path_list_free(GList * path_list)221 path_list_free (GList *path_list)
222 {
223 g_list_foreach (path_list, (GFunc) gtk_tree_row_reference_free, NULL);
224 g_list_free (path_list);
225 }
226
227 static void
set_context_data(GdkDragContext * context,GList * path_list)228 set_context_data (GdkDragContext *context,
229 GList *path_list)
230 {
231 g_object_set_data_full (G_OBJECT (context),
232 "egg-tree-view-multi-source-row",
233 path_list,
234 (GDestroyNotify) path_list_free);
235 }
236
237 static void
egg_tree_multi_drag_begin(GtkWidget * tree,GdkDragContext * context,gpointer user_data)238 egg_tree_multi_drag_begin (GtkWidget *tree,
239 GdkDragContext *context,
240 gpointer user_data)
241 {
242 gtk_drag_set_icon_default (context);
243 g_signal_stop_emission_by_name (tree, "drag-begin");
244 }
245
246 static GList *
get_context_data(GdkDragContext * context)247 get_context_data (GdkDragContext *context)
248 {
249 return g_object_get_data (G_OBJECT (context),
250 "egg-tree-view-multi-source-row");
251 }
252
253 /* CUT-N-PASTE from gtktreeview.c */
254 static TreeViewDragInfo*
get_info(GtkTreeView * tree_view)255 get_info (GtkTreeView *tree_view)
256 {
257 return g_object_get_data (G_OBJECT (tree_view), "gtk-tree-view-drag-info");
258 }
259
260
261 static void
egg_tree_multi_drag_drag_data_get(GtkWidget * widget,GdkDragContext * context,GtkSelectionData * selection_data,guint info,guint time)262 egg_tree_multi_drag_drag_data_get (GtkWidget *widget,
263 GdkDragContext *context,
264 GtkSelectionData *selection_data,
265 guint info,
266 guint time)
267 {
268 GtkTreeView *tree_view;
269 GtkTreeModel *model;
270 TreeViewDragInfo *di;
271 GList *path_list;
272
273 tree_view = GTK_TREE_VIEW (widget);
274
275 model = gtk_tree_view_get_model (tree_view);
276
277 if (model == NULL)
278 return;
279
280 di = get_info (GTK_TREE_VIEW (widget));
281
282 if (di == NULL)
283 return;
284
285 path_list = get_context_data (context);
286
287 if (path_list == NULL)
288 return;
289
290 /* We can implement the GTK_TREE_MODEL_ROW target generically for
291 * any model; for DragSource models there are some other targets
292 * we also support.
293 */
294
295 if (EGG_IS_TREE_MULTI_DRAG_SOURCE (model))
296 {
297 egg_tree_multi_drag_source_drag_data_get (EGG_TREE_MULTI_DRAG_SOURCE (model),
298 path_list,
299 selection_data);
300 }
301 }
302
303 static gboolean
egg_tree_multi_drag_motion_event(GtkWidget * widget,GdkEventMotion * event,gpointer data)304 egg_tree_multi_drag_motion_event (GtkWidget *widget,
305 GdkEventMotion *event,
306 gpointer data)
307 {
308 EggTreeMultiDndData *priv_data;
309
310 priv_data = g_object_get_data (G_OBJECT (widget), EGG_TREE_MULTI_DND_STRING);
311
312 if (gtk_drag_check_threshold (widget,
313 priv_data->x,
314 priv_data->y,
315 event->x,
316 event->y))
317 {
318 GList *path_list = NULL;
319 GtkTreeSelection *selection;
320 GtkTreeModel *model;
321 GdkDragContext *context;
322 TreeViewDragInfo *di;
323
324 di = get_info (GTK_TREE_VIEW (widget));
325
326 if (di == NULL)
327 return FALSE;
328
329 selection = gtk_tree_view_get_selection (GTK_TREE_VIEW (widget));
330 if (priv_data->motion_notify_handler) {
331 g_signal_handler_disconnect (widget, priv_data->motion_notify_handler);
332 priv_data->motion_notify_handler = 0;
333 }
334 if (priv_data->button_release_handler) {
335 g_signal_handler_disconnect (widget, priv_data->button_release_handler);
336 priv_data->button_release_handler = 0;
337 }
338 stop_drag_check (widget);
339 gtk_tree_selection_selected_foreach (selection, selection_foreach, &path_list);
340 path_list = g_list_reverse (path_list);
341 model = gtk_tree_view_get_model (GTK_TREE_VIEW (widget));
342 if (egg_tree_multi_drag_source_row_draggable (EGG_TREE_MULTI_DRAG_SOURCE (model), path_list))
343 {
344 gulong sig;
345
346 /* This is to disconnect the default signal handler for treeviews as
347 * it sometimes gives a warning. The default handler just sets the
348 * icon which we do as well in our callback so it is fine. */
349 sig = g_signal_connect (widget,
350 "drag-begin",
351 G_CALLBACK (egg_tree_multi_drag_begin),
352 NULL);
353 context = gtk_drag_begin (widget,
354 gtk_drag_source_get_target_list (widget),
355 di->source_actions,
356 priv_data->pressed_button,
357 (GdkEvent*)event);
358 g_signal_handler_disconnect (widget, sig);
359 set_context_data (context, path_list);
360 }
361 else
362 {
363 path_list_free (path_list);
364 }
365 }
366 return TRUE;
367 }
368
369 static gboolean
egg_tree_multi_drag_button_press_event(GtkWidget * widget,GdkEventButton * event,gpointer data)370 egg_tree_multi_drag_button_press_event (GtkWidget *widget,
371 GdkEventButton *event,
372 gpointer data)
373 {
374 GtkTreeView *tree_view;
375 GtkTreePath *path = NULL;
376 GtkTreeViewColumn *column = NULL;
377 gint cell_x, cell_y;
378 GtkTreeSelection *selection;
379 EggTreeMultiDndData *priv_data;
380
381 tree_view = GTK_TREE_VIEW (widget);
382 priv_data = g_object_get_data (G_OBJECT (tree_view), EGG_TREE_MULTI_DND_STRING);
383 if (priv_data == NULL)
384 {
385 priv_data = g_new0 (EggTreeMultiDndData, 1);
386 g_object_set_data (G_OBJECT (tree_view), EGG_TREE_MULTI_DND_STRING, priv_data);
387 }
388
389 if (g_slist_find (priv_data->event_list, event))
390 return FALSE;
391
392 if (priv_data->event_list)
393 {
394 /* save the event to be propagated in order */
395 priv_data->event_list = g_slist_append (priv_data->event_list, gdk_event_copy ((GdkEvent*)event));
396 return TRUE;
397 }
398
399 if (event->type == GDK_2BUTTON_PRESS)
400 return FALSE;
401
402 if (event->button == 3)
403 return FALSE;
404
405 gtk_tree_view_get_path_at_pos (tree_view,
406 event->x, event->y,
407 &path, &column,
408 &cell_x, &cell_y);
409
410 selection = gtk_tree_view_get_selection (GTK_TREE_VIEW (tree_view));
411 if (path && gtk_tree_selection_path_is_selected (selection, path))
412 {
413 priv_data->pressed_button = event->button;
414 priv_data->x = event->x;
415 priv_data->y = event->y;
416 priv_data->event_list = g_slist_append (priv_data->event_list, gdk_event_copy ((GdkEvent*)event));
417
418 priv_data->motion_notify_handler =
419 g_signal_connect (G_OBJECT (tree_view), "motion_notify_event", G_CALLBACK (egg_tree_multi_drag_motion_event), NULL);
420 priv_data->button_release_handler =
421 g_signal_connect (G_OBJECT (tree_view), "button_release_event", G_CALLBACK (egg_tree_multi_drag_button_release_event), NULL);
422
423 if (priv_data->drag_data_get_handler == 0)
424 {
425 priv_data->drag_data_get_handler =
426 g_signal_connect (G_OBJECT (tree_view), "drag_data_get", G_CALLBACK (egg_tree_multi_drag_drag_data_get), NULL);
427 }
428
429 gtk_tree_path_free (path);
430
431 return TRUE;
432 }
433
434 if (path)
435 {
436 gtk_tree_path_free (path);
437 }
438
439 return FALSE;
440 }
441
442 void
egg_tree_multi_drag_add_drag_support(GtkTreeView * tree_view)443 egg_tree_multi_drag_add_drag_support (GtkTreeView *tree_view)
444 {
445 g_return_if_fail (GTK_IS_TREE_VIEW (tree_view));
446 g_signal_connect (G_OBJECT (tree_view), "button_press_event", G_CALLBACK (egg_tree_multi_drag_button_press_event), NULL);
447 }
448
449