aboutsummaryrefslogtreecommitdiffstats
path: root/widgets/misc/e-canvas.c
blob: 230d5a72eab9dcf83b7beefec27b82ddb6d46b9b (plain) (blame)
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
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* 
 * e-canvas.c
 * Copyright (C) 2000  Helix Code, Inc.
 * Author: Chris Lahey <clahey@helixcode.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <gnome.h>
#include "e-canvas.h"
static void e_canvas_init           (ECanvas         *card);
static void e_canvas_destroy        (GtkObject        *object);
static void e_canvas_class_init     (ECanvasClass    *klass);
static void e_canvas_realize        (GtkWidget        *widget);
static gint e_canvas_key            (GtkWidget        *widget,
                     GdkEventKey      *event);

static gint e_canvas_focus_in       (GtkWidget        *widget,
                     GdkEventFocus    *event);
static gint e_canvas_focus_out      (GtkWidget        *widget,
                     GdkEventFocus    *event);

static int emit_event (GnomeCanvas *canvas, GdkEvent *event);

static GnomeCanvasClass *parent_class = NULL;

enum {
    REFLOW,
    LAST_SIGNAL
};

static guint e_canvas_signals [LAST_SIGNAL] = { 0, };

typedef struct {
    GnomeCanvasItem *item;
    gpointer         id;
} ECanvasSelectionInfo;

GtkType
e_canvas_get_type (void)
{
    static GtkType canvas_type = 0;
    
    if (!canvas_type)
    {
        static const GtkTypeInfo canvas_info =
        {
            "ECanvas",
            sizeof (ECanvas),
            sizeof (ECanvasClass),
            (GtkClassInitFunc) e_canvas_class_init,
            (GtkObjectInitFunc) e_canvas_init,
            /* reserved_1 */ NULL,
            /* reserved_2 */ NULL,
            (GtkClassInitFunc) NULL,
        };
        
        canvas_type = gtk_type_unique (gnome_canvas_get_type (), &canvas_info);
    }
    
    return canvas_type;
}

static void
e_canvas_class_init (ECanvasClass *klass)
{
    GtkObjectClass *object_class;
    GnomeCanvasClass *canvas_class;
    GtkWidgetClass *widget_class;
    
    object_class = (GtkObjectClass*) klass;
    canvas_class = (GnomeCanvasClass *) klass;
    widget_class = (GtkWidgetClass *) klass;
    
    parent_class = gtk_type_class (gnome_canvas_get_type ());

    object_class->destroy = e_canvas_destroy;

    widget_class->key_press_event = e_canvas_key;
    widget_class->key_release_event = e_canvas_key;
    widget_class->focus_in_event = e_canvas_focus_in;
    widget_class->focus_out_event = e_canvas_focus_out;
    widget_class->realize = e_canvas_realize;
    
    klass->reflow = NULL;

    e_canvas_signals [REFLOW] =
        gtk_signal_new ("reflow",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ECanvasClass, reflow),
                gtk_marshal_NONE__NONE,
                GTK_TYPE_NONE, 0);

    gtk_object_class_add_signals (object_class, e_canvas_signals, LAST_SIGNAL);
}

static void
e_canvas_init (ECanvas *canvas)
{
    canvas->selection = NULL;
}

static void
e_canvas_destroy (GtkObject *object)
{
    ECanvas *canvas = E_CANVAS(object);
    if (canvas->idle_id)
        g_source_remove(canvas->idle_id);
}

GtkWidget *
e_canvas_new ()
{
    return GTK_WIDGET (gtk_type_new (e_canvas_get_type ()));
}


/* Returns whether the item is an inferior of or is equal to the parent. */
static int
is_descendant (GnomeCanvasItem *item, GnomeCanvasItem *parent)
{
    for (; item; item = item->parent)
        if (item == parent)
            return TRUE;

    return FALSE;
}

/* Emits an event for an item in the canvas, be it the current item, grabbed
 * item, or focused item, as appropriate.
 */
static int
emit_event (GnomeCanvas *canvas, GdkEvent *event)
{
    GdkEvent ev;
    gint finished;
    GnomeCanvasItem *item;
    GnomeCanvasItem *parent;
    guint mask;

    /* Perform checks for grabbed items */

    if (canvas->grabbed_item && !is_descendant (canvas->current_item, canvas->grabbed_item))
        return FALSE;

    if (canvas->grabbed_item) {
        switch (event->type) {
        case GDK_ENTER_NOTIFY:
            mask = GDK_ENTER_NOTIFY_MASK;
            break;

        case GDK_LEAVE_NOTIFY:
            mask = GDK_LEAVE_NOTIFY_MASK;
            break;

        case GDK_MOTION_NOTIFY:
            mask = GDK_POINTER_MOTION_MASK;
            break;

        case GDK_BUTTON_PRESS:
        case GDK_2BUTTON_PRESS:
        case GDK_3BUTTON_PRESS:
            mask = GDK_BUTTON_PRESS_MASK;
            break;

        case GDK_BUTTON_RELEASE:
            mask = GDK_BUTTON_RELEASE_MASK;
            break;

        case GDK_KEY_PRESS:
            mask = GDK_KEY_PRESS_MASK;
            break;

        case GDK_KEY_RELEASE:
            mask = GDK_KEY_RELEASE_MASK;
            break;

        default:
            mask = 0;
            break;
        }

        if (!(mask & canvas->grabbed_event_mask))
            return FALSE;
    }

    /* Convert to world coordinates -- we have two cases because of diferent
     * offsets of the fields in the event structures.
     */

    ev = *event;

    switch (ev.type) {
    case GDK_ENTER_NOTIFY:
    case GDK_LEAVE_NOTIFY:
        gnome_canvas_window_to_world (canvas,
                          ev.crossing.x, ev.crossing.y,
                          &ev.crossing.x, &ev.crossing.y);
        break;

    case GDK_MOTION_NOTIFY:
    case GDK_BUTTON_PRESS:
    case GDK_2BUTTON_PRESS:
    case GDK_3BUTTON_PRESS:
    case GDK_BUTTON_RELEASE:
        gnome_canvas_window_to_world (canvas,
                          ev.motion.x, ev.motion.y,
                          &ev.motion.x, &ev.motion.y);
        break;

    default:
        break;
    }

    /* Choose where we send the event */

    item = canvas->current_item;

    if (canvas->focused_item
        && ((event->type == GDK_KEY_PRESS) || (event->type == GDK_KEY_RELEASE) || (event->type == GDK_FOCUS_CHANGE)))
        item = canvas->focused_item;

    /* The event is propagated up the hierarchy (for if someone connected to
     * a group instead of a leaf event), and emission is stopped if a
     * handler returns TRUE, just like for GtkWidget events.
     */

    finished = FALSE;

    while (item && !finished) {
        gtk_object_ref (GTK_OBJECT (item));

        gtk_signal_emit_by_name (GTK_OBJECT (item), "event",
                     &ev,
                     &finished);

        if (GTK_OBJECT_DESTROYED (item))
            finished = TRUE;

        parent = item->parent;
        gtk_object_unref (GTK_OBJECT (item));

        item = parent;
    }

    return finished;
}

/* Key event handler for the canvas */
static gint
e_canvas_key (GtkWidget *widget, GdkEventKey *event)
{
    GnomeCanvas *canvas;

    g_return_val_if_fail (widget != NULL, FALSE);
    g_return_val_if_fail (GNOME_IS_CANVAS (widget), FALSE);
    g_return_val_if_fail (event != NULL, FALSE);

    canvas = GNOME_CANVAS (widget);

    return emit_event (canvas, (GdkEvent *) event);
}


/**
 * e_canvas_item_grab_focus:
 * @item: A canvas item.
 *
 * Makes the specified item take the keyboard focus, so all keyboard events will
 * be sent to it.  If the canvas widget itself did not have the focus, it grabs
 * it as well.
 **/
void
e_canvas_item_grab_focus (GnomeCanvasItem *item)
{
    GnomeCanvasItem *focused_item;
    GdkEvent ev;

    g_return_if_fail (item != NULL);
    g_return_if_fail (GNOME_IS_CANVAS_ITEM (item));
    g_return_if_fail (GTK_WIDGET_CAN_FOCUS (GTK_WIDGET (item->canvas)));

    focused_item = item->canvas->focused_item;

    if (focused_item) {
        ev.focus_change.type = GDK_FOCUS_CHANGE;
        ev.focus_change.window = GTK_LAYOUT (item->canvas)->bin_window;
        ev.focus_change.send_event = FALSE;
        ev.focus_change.in = FALSE;

        emit_event (item->canvas, &ev);
    }

    item->canvas->focused_item = item;

    if (!GTK_WIDGET_HAS_FOCUS (GTK_WIDGET(item->canvas))) {
        gtk_widget_grab_focus (GTK_WIDGET (item->canvas));
    }
    
    if (focused_item) {
        ev.focus_change.type = GDK_FOCUS_CHANGE;
        ev.focus_change.window = GTK_LAYOUT (item->canvas)->bin_window;
        ev.focus_change.send_event = FALSE;
        ev.focus_change.in = TRUE;
        
        emit_event (item->canvas, &ev);
    }
}

/* Focus in handler for the canvas */
static gint
e_canvas_focus_in (GtkWidget *widget, GdkEventFocus *event)
{
    GnomeCanvas *canvas;

    canvas = GNOME_CANVAS (widget);

    GTK_WIDGET_SET_FLAGS (widget, GTK_HAS_FOCUS);

    if (canvas->focused_item)
        return emit_event (canvas, (GdkEvent *) event);
    else
        return FALSE;
}

/* Focus out handler for the canvas */
static gint
e_canvas_focus_out (GtkWidget *widget, GdkEventFocus *event)
{
    GnomeCanvas *canvas;

    canvas = GNOME_CANVAS (widget);

    GTK_WIDGET_UNSET_FLAGS (widget, GTK_HAS_FOCUS);

    if (canvas->focused_item)
        return emit_event (canvas, (GdkEvent *) event);
    else
        return FALSE;
}

static void
e_canvas_realize (GtkWidget *widget)
{
    if (GTK_WIDGET_CLASS (parent_class)->realize)
        (* GTK_WIDGET_CLASS (parent_class)->realize) (widget);
    
    gdk_window_set_back_pixmap (GTK_LAYOUT (widget)->bin_window, NULL, FALSE);
}

static void
e_canvas_item_invoke_reflow (GnomeCanvasItem *item, int flags)
{
    GnomeCanvasGroup *group;
    GList *list;
    GnomeCanvasItem *child;

    if (GNOME_IS_CANVAS_GROUP (item)) {
        group = GNOME_CANVAS_GROUP (item);
        for (list = group->item_list; list; list = list->next) {
            child = GNOME_CANVAS_ITEM (list->data);
            if (child->object.flags & E_CANVAS_ITEM_DESCENDENT_NEEDS_REFLOW)
                e_canvas_item_invoke_reflow (child, flags);
        }
    }
    
    if (item->object.flags & E_CANVAS_ITEM_NEEDS_REFLOW) {
        ECanvasItemReflowFunc func;
        func = gtk_object_get_data (GTK_OBJECT (item),
                        "ECanvasItem::reflow_callback");
        if (func)
            func (item, flags);
    }

    item->object.flags &= ~E_CANVAS_ITEM_NEEDS_REFLOW;
    item->object.flags &= ~E_CANVAS_ITEM_DESCENDENT_NEEDS_REFLOW;
}

static void
do_reflow (ECanvas *canvas)
{
    if (GNOME_CANVAS(canvas)->root->object.flags & E_CANVAS_ITEM_DESCENDENT_NEEDS_REFLOW)
        e_canvas_item_invoke_reflow (GNOME_CANVAS(canvas)->root, 0);
}

/* Idle handler for the e-canvas.  It deals with pending reflows. */
static gint
idle_handler (gpointer data)
{
    ECanvas *canvas;

    GDK_THREADS_ENTER();

    canvas = E_CANVAS (data);
    do_reflow (canvas);

    /* Reset idle id */
    canvas->idle_id = 0;

    gtk_signal_emit (GTK_OBJECT (canvas),
             e_canvas_signals [REFLOW]);

    GDK_THREADS_LEAVE();

    return FALSE;
}

/* Convenience function to add an idle handler to a canvas */
static void
add_idle (ECanvas *canvas)
{
    if (canvas->idle_id != 0)
        return;

    canvas->idle_id = g_idle_add_full (G_PRIORITY_HIGH_IDLE, idle_handler, (gpointer) canvas, NULL);
}

static void
e_canvas_item_descendent_needs_reflow (GnomeCanvasItem *item)
{
    if (item->object.flags & E_CANVAS_ITEM_DESCENDENT_NEEDS_REFLOW)
        return;

    item->object.flags |= E_CANVAS_ITEM_DESCENDENT_NEEDS_REFLOW;
    if (item->parent)
        e_canvas_item_descendent_needs_reflow(item->parent);
}

void
e_canvas_item_request_reflow (GnomeCanvasItem *item)
{
    if (item->object.flags & GNOME_CANVAS_ITEM_REALIZED) {
        item->object.flags |= E_CANVAS_ITEM_NEEDS_REFLOW;
        e_canvas_item_descendent_needs_reflow(item);
        add_idle(E_CANVAS(item->canvas));
    }
}

void
e_canvas_item_request_parent_reflow (GnomeCanvasItem *item)
{
    g_return_if_fail(item != NULL);
    g_return_if_fail(GNOME_IS_CANVAS_ITEM(item));
    e_canvas_item_request_reflow(item->parent);
}

void
e_canvas_item_set_reflow_callback (GnomeCanvasItem *item, ECanvasItemReflowFunc func)
{
    gtk_object_set_data(GTK_OBJECT(item), "ECanvasItem::reflow_callback", (gpointer) func);
}


void
e_canvas_item_set_selection_callback (GnomeCanvasItem *item, ECanvasItemSelectionFunc func)
{
    gtk_object_set_data(GTK_OBJECT(item), "ECanvasItem::selection_callback", (gpointer) func);
}

void
e_canvas_item_set_selection_compare_callback (GnomeCanvasItem *item, ECanvasItemSelectionCompareFunc func)
{
    gtk_object_set_data(GTK_OBJECT(item), "ECanvasItem::selection_compare_callback", (gpointer) func);
}

void
e_canvas_item_set_cursor (GnomeCanvasItem *item, gpointer id)
{
    GList *list;
    int flags;
    ECanvas *canvas;
    ECanvasSelectionInfo *info;
    ECanvasItemSelectionFunc func;

    g_return_if_fail(item != NULL);
    g_return_if_fail(GNOME_IS_CANVAS_ITEM(item));
    g_return_if_fail(item->canvas != NULL);
    g_return_if_fail(E_IS_CANVAS(item->canvas));

    canvas = E_CANVAS(item->canvas);
    flags = E_CANVAS_ITEM_SELECTION_DELETE_DATA;

    for (list = canvas->selection; list; list = g_list_next(list)) {
        info = list->data;

        func = gtk_object_get_data(GTK_OBJECT(info->item), "ECanvasItem::selection_callback");
        if (func)
            func(info->item, flags, info->id);
        g_free(info);
    }
    g_list_free(canvas->selection);

    canvas->selection = NULL;
    
    info = g_new(ECanvasSelectionInfo, 1);
    info->item = item;
    info->id = id;
    
    flags = E_CANVAS_ITEM_SELECTION_SELECT | E_CANVAS_ITEM_SELECTION_CURSOR;
    func = gtk_object_get_data(GTK_OBJECT(item), "ECanvasItem::selection_callback");
    if (func)
        func(item, flags, id);
    
    canvas->selection = g_list_prepend(canvas->selection, info);
}

void
e_canvas_item_set_cursor_end (GnomeCanvasItem *item, gpointer id)
{
}

void
e_canvas_item_add_selection (GnomeCanvasItem *item, gpointer id)
{
    int flags;
    ECanvas *canvas;
    ECanvasSelectionInfo *info;
    ECanvasItemSelectionFunc func;

    g_return_if_fail(item != NULL);
    g_return_if_fail(GNOME_IS_CANVAS_ITEM(item));
    g_return_if_fail(item->canvas != NULL);
    g_return_if_fail(E_IS_CANVAS(item->canvas));

    flags = E_CANVAS_ITEM_SELECTION_SELECT | E_CANVAS_ITEM_SELECTION_CURSOR;
    canvas = E_CANVAS(item->canvas);

    info = g_new(ECanvasSelectionInfo, 1);
    info->item = item;
    info->id = id;

    func = gtk_object_get_data(GTK_OBJECT(item), "ECanvasItem::selection_callback");
    if (func)
        func(item, flags, id);
    
    canvas->selection = g_list_prepend(canvas->selection, info);
}

void
e_canvas_item_remove_selection (GnomeCanvasItem *item, gpointer id)
{
    int flags;
    ECanvas *canvas;
    ECanvasSelectionInfo *info;
    GList *list;

    g_return_if_fail(item != NULL);
    g_return_if_fail(GNOME_IS_CANVAS_ITEM(item));
    g_return_if_fail(item->canvas != NULL);
    g_return_if_fail(E_IS_CANVAS(item->canvas));

    flags = E_CANVAS_ITEM_SELECTION_DELETE_DATA;
    canvas = E_CANVAS(item->canvas);

    for (list = canvas->selection; list; list = g_list_next(list)) {
        info = list->data;
        
        if (info->item == item) {
            ECanvasItemSelectionCompareFunc compare_func;
            compare_func = gtk_object_get_data(GTK_OBJECT(info->item), "ECanvasItem::selection_compare_callback");
            if (compare_func(info->item, info->id, id, 0) == 0) {
                ECanvasItemSelectionFunc func;
                func = gtk_object_get_data(GTK_OBJECT(info->item), "ECanvasItem::selection_callback");
                if (func)
                    func(info->item, flags, info->id);
                canvas->selection = g_list_remove_link(canvas->selection, list);
                g_free(info);
                g_list_free_1(list);
                break;
            }
        }
    }
}