summaryrefslogtreecommitdiff
path: root/src/eggtreemultidnd.c
blob: 28fda8e734dfb4bd94ccb5ec2555489fdf96dd0d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
/*
 * Engrampa
 *
 * Copyright (C) 2005 Free Software Foundation, Inc.
 * Author: Paolo Bacchilega
 */

/* eggtreemultidnd.c
 * Copyright (C) 2001  Red Hat, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include <string.h>
#include <gtk/gtk.h>
#include "eggtreemultidnd.h"

#define EGG_TREE_MULTI_DND_STRING "EggTreeMultiDndString"

static GtkTargetEntry target_table[] = {
        { "XdndDirectSave0", 0, 0 },
        { "XdndEngrampa0", 0, 1 }
};

typedef struct
{
  guint   pressed_button;
  gint    x;
  gint    y;
  guint   motion_notify_handler;
  guint   button_release_handler;
  guint   drag_data_get_handler;
  GSList *event_list;
  gboolean pending_event;
} EggTreeMultiDndData;

GType
egg_tree_multi_drag_source_get_type (void)
{
  static GType our_type = 0;

  if (!our_type)
    {
      static const GTypeInfo our_info =
	{
	  sizeof (EggTreeMultiDragSourceIface), /* class_size */
	  NULL,		/* base_init */
	  NULL,		/* base_finalize */
	  NULL,
	  NULL,		/* class_finalize */
	  NULL,		/* class_data */
	  0,
	  0,            /* n_preallocs */
	  NULL,
	  NULL
	};

      our_type = g_type_register_static (G_TYPE_INTERFACE,
					 "EggTreeMultiDragSource",
					 &our_info,
					 0);
    }

  return our_type;
}

/**
 * egg_tree_multi_drag_source_row_draggable:
 * @drag_source: a #EggTreeMultiDragSource
 * @path: row on which user is initiating a drag
 *
 * Asks the #EggTreeMultiDragSource whether a particular row can be used as
 * the source of a DND operation. If the source doesn't implement
 * this interface, the row is assumed draggable.
 *
 * Return value: %TRUE if the row can be dragged
 **/
gboolean
egg_tree_multi_drag_source_row_draggable (EggTreeMultiDragSource *drag_source,
					  GList                  *path_list)
{
  EggTreeMultiDragSourceIface *iface = EGG_TREE_MULTI_DRAG_SOURCE_GET_IFACE (drag_source);

  g_return_val_if_fail (EGG_IS_TREE_MULTI_DRAG_SOURCE (drag_source), FALSE);
  g_return_val_if_fail (iface->row_draggable != NULL, FALSE);
  g_return_val_if_fail (path_list != NULL, FALSE);

  if (iface->row_draggable)
    return (* iface->row_draggable) (drag_source, path_list);
  else
    return TRUE;
}

/**
 * egg_tree_multi_drag_source_drag_data_delete:
 * @drag_source: a #EggTreeMultiDragSource
 * @path: row that was being dragged
 *
 * Asks the #EggTreeMultiDragSource to delete the row at @path, because
 * it was moved somewhere else via drag-and-drop. Returns %FALSE
 * if the deletion fails because @path no longer exists, or for
 * some model-specific reason. Should robustly handle a @path no
 * longer found in the model!
 *
 * Return value: %TRUE if the row was successfully deleted
 **/
gboolean
egg_tree_multi_drag_source_drag_data_delete (EggTreeMultiDragSource *drag_source,
					     GList                  *path_list)
{
  EggTreeMultiDragSourceIface *iface = EGG_TREE_MULTI_DRAG_SOURCE_GET_IFACE (drag_source);

  g_return_val_if_fail (EGG_IS_TREE_MULTI_DRAG_SOURCE (drag_source), FALSE);
  g_return_val_if_fail (iface->drag_data_delete != NULL, FALSE);
  g_return_val_if_fail (path_list != NULL, FALSE);

  return (* iface->drag_data_delete) (drag_source, path_list);
}

/**
 * egg_tree_multi_drag_source_drag_data_get:
 * @drag_source: a #EggTreeMultiDragSource
 * @path: row that was dragged
 * @selection_data: a #EggSelectionData to fill with data from the dragged row
 *
 * Asks the #EggTreeMultiDragSource to fill in @selection_data with a
 * representation of the row at @path. @selection_data->target gives
 * the required type of the data.  Should robustly handle a @path no
 * longer found in the model!
 *
 * Return value: %TRUE if data of the required type was provided
 **/
gboolean
egg_tree_multi_drag_source_drag_data_get (EggTreeMultiDragSource *drag_source,
					  GdkDragContext         *context,
					  GtkSelectionData       *selection_data,
					  GList                  *path_list)
{
  EggTreeMultiDragSourceIface *iface = EGG_TREE_MULTI_DRAG_SOURCE_GET_IFACE (drag_source);

  g_return_val_if_fail (EGG_IS_TREE_MULTI_DRAG_SOURCE (drag_source), FALSE);
  g_return_val_if_fail (iface->drag_data_get != NULL, FALSE);
  g_return_val_if_fail (path_list != NULL, FALSE);
  g_return_val_if_fail (selection_data != NULL, FALSE);

  return (* iface->drag_data_get) (drag_source, context, selection_data, path_list);
}

static void
stop_drag_check (GtkWidget *widget)
{
  EggTreeMultiDndData *priv_data;
  GSList *l;

  priv_data = g_object_get_data (G_OBJECT (widget), EGG_TREE_MULTI_DND_STRING);

  for (l = priv_data->event_list; l != NULL; l = l->next)
    gdk_event_free (l->data);

  g_slist_free (priv_data->event_list);
  priv_data->event_list = NULL;
  priv_data->pending_event = FALSE;

  if (priv_data->motion_notify_handler) {
    g_signal_handler_disconnect (widget, priv_data->motion_notify_handler);
    priv_data->motion_notify_handler = 0;
  }
  if (priv_data->button_release_handler) {
    g_signal_handler_disconnect (widget, priv_data->button_release_handler);
    priv_data->button_release_handler = 0;
  }
}

static gboolean
egg_tree_multi_drag_button_release_event (GtkWidget      *widget,
					  GdkEventButton *event,
					  gpointer        data)
{
  EggTreeMultiDndData *priv_data;
  GSList *l;

  priv_data = g_object_get_data (G_OBJECT (widget), EGG_TREE_MULTI_DND_STRING);

  for (l = priv_data->event_list; l != NULL; l = l->next)
    gtk_propagate_event (widget, l->data);

  stop_drag_check (widget);

  return FALSE;
}

static void
selection_foreach (GtkTreeModel *model,
		   GtkTreePath  *path,
		   GtkTreeIter  *iter,
		   gpointer      data)
{
  GList **list_ptr;

  list_ptr = (GList **) data;

  *list_ptr = g_list_prepend (*list_ptr, gtk_tree_row_reference_new (model, path));
}

static void
path_list_free (GList *path_list)
{
  g_list_foreach (path_list, (GFunc) gtk_tree_row_reference_free, NULL);
  g_list_free (path_list);
}

static void
set_context_data (GdkDragContext *context,
		  GList          *path_list)
{
  g_object_set_data_full (G_OBJECT (context),
                          "egg-tree-view-multi-source-row",
                          path_list,
                          (GDestroyNotify) path_list_free);
}

static GList *
get_context_data (GdkDragContext *context)
{
  return g_object_get_data (G_OBJECT (context),
			    "egg-tree-view-multi-source-row");
}

static gboolean
egg_tree_multi_drag_drag_data_get (GtkWidget        *widget,
				   GdkDragContext   *context,
				   GtkSelectionData *selection_data,
				   guint             info,
				   guint             time)
{
  GtkTreeView  *tree_view;
  GtkTreeModel *model;
  GList        *path_list;

  tree_view = GTK_TREE_VIEW (widget);
  model = gtk_tree_view_get_model (tree_view);
  if (model == NULL)
    return FALSE;

  path_list = get_context_data (context);
  if (path_list == NULL)
    return FALSE;

  /* We can implement the GTK_TREE_MODEL_ROW target generically for
   * any model; for DragSource models there are some other targets
   * we also support.
   */

  if (! EGG_IS_TREE_MULTI_DRAG_SOURCE (model))
    return FALSE;

  return egg_tree_multi_drag_source_drag_data_get (EGG_TREE_MULTI_DRAG_SOURCE (model),
      						   context,
						   selection_data,
						   path_list);
}

static gboolean
egg_tree_multi_drag_motion_event (GtkWidget      *widget,
				  GdkEventMotion *event,
				  gpointer        data)
{
  EggTreeMultiDndData *priv_data;

  priv_data = g_object_get_data (G_OBJECT (widget), EGG_TREE_MULTI_DND_STRING);

  if (gtk_drag_check_threshold (widget,
				priv_data->x,
				priv_data->y,
				(gint) event->x,
				(gint) event->y))
    {
      GList            *path_list = NULL;
      GtkTreeSelection *selection;
      GtkTreeModel     *model;

      stop_drag_check (widget);

      selection = gtk_tree_view_get_selection (GTK_TREE_VIEW (widget));
      gtk_tree_selection_selected_foreach (selection, selection_foreach, &path_list);
      if (path_list == NULL)
	      return FALSE;

      path_list = g_list_reverse (path_list);

      model = gtk_tree_view_get_model (GTK_TREE_VIEW (widget));
      if (egg_tree_multi_drag_source_row_draggable (EGG_TREE_MULTI_DRAG_SOURCE (model), path_list))
	{
	  GdkDragContext *context;
	  GtkTargetList  *target_list;
	  GtkTreePath    *tree_path;
	  int             cell_x;
	  int             cell_y;

	  target_list = gtk_target_list_new (target_table, G_N_ELEMENTS (target_table));
	  context = gtk_drag_begin_with_coordinates (widget,
	                                             target_list,
	                                             GDK_ACTION_COPY,
	                                             priv_data->pressed_button,
	                                             (GdkEvent*) event,
	                                             (gint) event->x,
	                                             (gint) event->y);
	  set_context_data (context, path_list);

	  if (gtk_tree_view_get_path_at_pos (GTK_TREE_VIEW (widget),
					     priv_data->x,
					     priv_data->y,
					     &tree_path,
					     NULL,
					     &cell_x,
					     &cell_y))
	  {
		  cairo_surface_t *drag_icon;

		  drag_icon = gtk_tree_view_create_row_drag_icon (GTK_TREE_VIEW (widget), tree_path);
		  cairo_surface_set_device_offset (drag_icon, -cell_x, -cell_y);
		  gtk_drag_set_icon_surface (context, drag_icon);

		  cairo_surface_destroy (drag_icon);
		  gtk_tree_path_free (tree_path);
	  }
	  else
		  gtk_drag_set_icon_default (context);

	  gtk_target_list_unref (target_list);
	}
      else
	{
	  path_list_free (path_list);
	}
    }

  return TRUE;
}

static gboolean
egg_tree_multi_drag_button_press_event (GtkWidget      *widget,
					GdkEventButton *event,
					gpointer        data)
{
  GtkTreeView         *tree_view;
  GtkTreePath         *path = NULL;
  GtkTreeViewColumn   *column = NULL;
  gint                 cell_x, cell_y;
  GtkTreeSelection    *selection;
  EggTreeMultiDndData *priv_data;

  if (event->window != gtk_tree_view_get_bin_window (GTK_TREE_VIEW (widget)))
    return FALSE;

  if (event->button == 3)
    return FALSE;

  tree_view = GTK_TREE_VIEW (widget);
  priv_data = g_object_get_data (G_OBJECT (tree_view), EGG_TREE_MULTI_DND_STRING);
  if (priv_data == NULL)
    {
      priv_data = g_new0 (EggTreeMultiDndData, 1);
      priv_data->pending_event = FALSE;
      g_object_set_data (G_OBJECT (tree_view),
			 EGG_TREE_MULTI_DND_STRING,
			 priv_data);
    }

  if (g_slist_find (priv_data->event_list, event))
    return FALSE;

  if (priv_data->pending_event)
    {
      /* save the event to be propagated in order */
      priv_data->event_list = g_slist_append (priv_data->event_list,
					      gdk_event_copy ((GdkEvent*)event));
      return TRUE;
    }

  if (event->type == GDK_2BUTTON_PRESS)
    return FALSE;

  gtk_tree_view_get_path_at_pos (tree_view,
				 (gint) event->x, (gint) event->y,
				 &path, &column,
				 &cell_x, &cell_y);

  selection = gtk_tree_view_get_selection (tree_view);

  if (path)
    {
      gboolean call_parent = (event->state & (GDK_CONTROL_MASK | GDK_SHIFT_MASK) ||
			      !gtk_tree_selection_path_is_selected (selection, path) ||
			      event->button != 1);

      if (call_parent)
	(GTK_WIDGET_GET_CLASS (tree_view))->button_press_event (widget, event);

      if (gtk_tree_selection_path_is_selected (selection, path))
    {
      priv_data->pressed_button = event->button;
      priv_data->x = (gint) event->x;
      priv_data->y = (gint) event->y;

      priv_data->pending_event = TRUE;
      if (!call_parent)
	priv_data->event_list = g_slist_append (priv_data->event_list,
						gdk_event_copy ((GdkEvent*)event));

      if (priv_data->motion_notify_handler == 0)
        {
          priv_data->motion_notify_handler =
	    g_signal_connect (G_OBJECT (tree_view),
	  		      "motion_notify_event",
			      G_CALLBACK (egg_tree_multi_drag_motion_event),
			      NULL);
        }

      if (priv_data->button_release_handler == 0)
        {
          priv_data->button_release_handler =
	    g_signal_connect (G_OBJECT (tree_view),
	 		      "button_release_event",
			      G_CALLBACK (egg_tree_multi_drag_button_release_event),
			      NULL);
        }

      if (priv_data->drag_data_get_handler == 0)
	{
	  priv_data->drag_data_get_handler =
	    g_signal_connect (G_OBJECT (tree_view),
			      "drag_data_get",
			      G_CALLBACK (egg_tree_multi_drag_drag_data_get),
			      NULL);
	}
    }

      gtk_tree_path_free (path);
      /* We called the default handler so we don't let the default handler run */
      return TRUE;
    }

  return FALSE;
}

void
egg_tree_multi_drag_add_drag_support (GtkTreeView *tree_view)
{
  g_return_if_fail (GTK_IS_TREE_VIEW (tree_view));
  g_signal_connect (G_OBJECT (tree_view),
		    "button_press_event",
		    G_CALLBACK (egg_tree_multi_drag_button_press_event),
		    NULL);
}