summaryrefslogtreecommitdiff
path: root/src/AppWindow.vala
blob: bfdfcaf4892c1303f52fa657283724ca068eb2ea (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
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
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
/* Copyright 2016 Software Freedom Conservancy Inc.
 *
 * This software is licensed under the GNU LGPL (version 2.1 or later).
 * See the COPYING file in this distribution.
 */

public class FullscreenWindow : PageWindow {
    public const int TOOLBAR_INVOCATION_MSEC = 250;
    public const int TOOLBAR_DISMISSAL_SEC = 2;
    public const int TOOLBAR_CHECK_DISMISSAL_MSEC = 500;
    
    private Gtk.Overlay overlay = new Gtk.Overlay();
    private Gtk.Toolbar toolbar = null;
    private Gtk.ToolButton close_button = new Gtk.ToolButton(null, null);
    private Gtk.ToggleToolButton pin_button = new Gtk.ToggleToolButton();
    private bool is_toolbar_shown = false;
    private bool waiting_for_invoke = false;
    private time_t left_toolbar_time = 0;
    private bool switched_to = false;
    private bool is_toolbar_dismissal_enabled;

    private const GLib.ActionEntry[] entries = {
        { "LeaveFullscreen", on_close }
    };

    public FullscreenWindow(Page page) {
        base ();

        set_current_page(page);

        this.add_action_entries (entries, this);
        const string[] accels = { "F11", null };
        Application.set_accels_for_action ("win.LeaveFullscreen", accels);

        set_screen(AppWindow.get_instance().get_screen());
        
        // Needed so fullscreen will occur on correct monitor in multi-monitor setups
        Gdk.Rectangle monitor = get_monitor_geometry();
        move(monitor.x, monitor.y);
        
        set_border_width(0);

        // restore pin state
        is_toolbar_dismissal_enabled = Config.Facade.get_instance().get_pin_toolbar_state();
        
        pin_button.set_icon_name("pin-toolbar");
        pin_button.set_label(_("Pin Toolbar"));
        pin_button.set_tooltip_text(_("Pin the toolbar open"));
        pin_button.set_active(!is_toolbar_dismissal_enabled);
        pin_button.clicked.connect(update_toolbar_dismissal);
        
        close_button.set_icon_name("view-restore");
        close_button.set_tooltip_text(_("Leave fullscreen"));
        close_button.set_action_name ("win.LeaveFullscreen");
        
        toolbar = page.get_toolbar();
        toolbar.set_show_arrow(false);
        toolbar.valign = Gtk.Align.END;
        toolbar.halign = Gtk.Align.CENTER;
        toolbar.expand = false;
        toolbar.opacity = Resources.TRANSIENT_WINDOW_OPACITY;

        if (page is SlideshowPage) {
            // slideshow page doesn't own toolbar to hide it, subscribe to signal instead
            ((SlideshowPage) page).hide_toolbar.connect(hide_toolbar);
        } else {
            // only non-slideshow pages should have pin button
            toolbar.insert(pin_button, -1); 
        }

        page.set_cursor_hide_time(TOOLBAR_DISMISSAL_SEC * 1000);
        page.start_cursor_hiding();

        toolbar.insert(close_button, -1);
        
        add(overlay);
        overlay.add(page);
        overlay.add_overlay (toolbar);

        // call to set_default_size() saves one repaint caused by changing
        // size from default to full screen. In slideshow mode, this change
        // also causes pixbuf cache updates, so it really saves some work.
        set_default_size(monitor.width, monitor.height);
        
        // need to create a Gdk.Window to set masks
        fullscreen();
        show_all();

        // capture motion events to show the toolbar
        add_events(Gdk.EventMask.POINTER_MOTION_MASK);
        
        // start off with toolbar invoked, as a clue for the user
        invoke_toolbar();

        // Toolbar steals keyboard focus from page, put it back again
        page.grab_focus ();

        // Do not show menubar in fullscreen
        set_show_menubar (false);
    }

    public void disable_toolbar_dismissal() {
        is_toolbar_dismissal_enabled = false;
    }
    
    public void update_toolbar_dismissal() {
        is_toolbar_dismissal_enabled = !pin_button.get_active();
    }

    private Gdk.Rectangle get_monitor_geometry() {
        Gdk.Rectangle monitor;

        get_screen().get_monitor_geometry(
            get_screen().get_monitor_at_window(AppWindow.get_instance().get_window()), out monitor);

        return monitor;
    }
    
    public override bool configure_event(Gdk.EventConfigure event) {
        bool result = base.configure_event(event);
        
        if (!switched_to) {
            get_current_page().switched_to();
            switched_to = true;
        }
        
        return result;
    }

    public override bool key_press_event(Gdk.EventKey event) {
        // check for an escape/abort 
        if (Gdk.keyval_name(event.keyval) == "Escape") {
            on_close();
            
            return true;
        }
        
        // propagate to this (fullscreen) window respecting "stop propagation" result...
        if (base.key_press_event != null && base.key_press_event(event))
            return true;
        
        // ... then propagate to the underlying window hidden behind this fullscreen one
        return AppWindow.get_instance().key_press_event(event);
    }
    
    private void on_close() {
        Config.Facade.get_instance().set_pin_toolbar_state(is_toolbar_dismissal_enabled);
        hide_toolbar();
        
        AppWindow.get_instance().end_fullscreen();
    }
    
    public new void close() {
        on_close();
    }
    
    public override void destroy() {
        Page? page = get_current_page();
        clear_current_page();
        
        if (page != null) {
            page.stop_cursor_hiding();
            page.switching_from();
        }
        
        base.destroy();
    }
    
    public override bool delete_event(Gdk.EventAny event) {
        on_close();
        AppWindow.get_instance().destroy();
        
        return true;
    }
    
    public override bool motion_notify_event(Gdk.EventMotion event) {
        if (!is_toolbar_shown) {
            // if pointer is in toolbar height range without the mouse down (i.e. in the middle of
            // an edit operation) and it stays there the necessary amount of time, invoke the
            // toolbar
            if (!waiting_for_invoke && is_pointer_in_toolbar()) {
                Timeout.add(TOOLBAR_INVOCATION_MSEC, on_check_toolbar_invocation);
                waiting_for_invoke = true;
            }
        }
        
        return (base.motion_notify_event != null) ? base.motion_notify_event(event) : false;
    }
    
    private bool is_pointer_in_toolbar() {
        Gdk.DeviceManager? devmgr = get_display().get_device_manager();
        if (devmgr == null) {
            debug("No device manager for display");
            
            return false;
        }
        
        int py;
        devmgr.get_client_pointer().get_position(null, null, out py);
        
        int wy;
        toolbar.get_window().get_geometry(null, out wy, null, null);

        return (py >= wy);
    }
    
    private bool on_check_toolbar_invocation() {
        waiting_for_invoke = false;
        
        if (is_toolbar_shown)
            return false;
        
        if (!is_pointer_in_toolbar())
            return false;
        
        invoke_toolbar();
        
        return false;
    }
    
    private void invoke_toolbar() {
        toolbar.show_all();

        is_toolbar_shown = true;
        
        Timeout.add(TOOLBAR_CHECK_DISMISSAL_MSEC, on_check_toolbar_dismissal);
    }
    
    private bool on_check_toolbar_dismissal() {
        if (!is_toolbar_shown)
            return false;
        
        // if dismissal is disabled, keep open but keep checking
        if ((!is_toolbar_dismissal_enabled))
            return true;
        
        // if the pointer is in toolbar range, keep it alive, but keep checking
        if (is_pointer_in_toolbar()) {
            left_toolbar_time = 0;

            return true;
        }
        
        // if this is the first time noticed, start the timer and keep checking
        if (left_toolbar_time == 0) {
            left_toolbar_time = time_t();
            
            return true;
        }
        
        // see if enough time has elapsed
        time_t now = time_t();
        assert(now >= left_toolbar_time);

        if (now - left_toolbar_time < TOOLBAR_DISMISSAL_SEC)
            return true;
        
        hide_toolbar();
        
        return false;
    }
    
    private void hide_toolbar() {
        toolbar.hide();
        is_toolbar_shown = false;
    }
}

// PageWindow is a Gtk.Window with essential functions for hosting a Page.  There may be more than
// one PageWindow in the system, and closing one does not imply exiting the application.
//
// PageWindow offers support for hosting a single Page; multiple Pages must be handled by the
// subclass.  A subclass should set current_page to the user-visible Page for it to receive
// various notifications.  It is the responsibility of the subclass to notify Pages when they're
// switched to and from, and other aspects of the Page interface.
public abstract class PageWindow : Gtk.ApplicationWindow {
    private Page current_page = null;
    private int busy_counter = 0;
    
    protected virtual void switched_pages(Page? old_page, Page? new_page) {
    }
    
    public PageWindow() {
        Object (application: Application.get_instance().get_system_app ());

        // the current page needs to know when modifier keys are pressed
        add_events(Gdk.EventMask.KEY_PRESS_MASK | Gdk.EventMask.KEY_RELEASE_MASK
            | Gdk.EventMask.STRUCTURE_MASK);
        set_show_menubar (true);
    }
    
    public Page? get_current_page() {
        return current_page;
    }
    
    public virtual void set_current_page(Page page) {
        if (current_page != null)
            current_page.clear_container();
        
        Page? old_page = current_page;
        current_page = page;
        current_page.set_container(this);
        
        switched_pages(old_page, page);
    }
    
    public virtual void clear_current_page() {
        if (current_page != null)
            current_page.clear_container();
        
        Page? old_page = current_page;
        current_page = null;
        
        switched_pages(old_page, null);
    }
    
    public override bool key_press_event(Gdk.EventKey event) {
        if (get_focus() is Gtk.Entry && get_focus().key_press_event(event))
            return true;
        
        if (current_page != null && current_page.notify_app_key_pressed(event))
            return true;
        
        return (base.key_press_event != null) ? base.key_press_event(event) : false;
    }
    
    public override bool key_release_event(Gdk.EventKey event) {
        if (get_focus() is Gtk.Entry && get_focus().key_release_event(event))
            return true;
       
        if (current_page != null && current_page.notify_app_key_released(event))
                return true;
        
        return (base.key_release_event != null) ? base.key_release_event(event) : false;
    }

    public override bool focus_in_event(Gdk.EventFocus event) {
        if (current_page != null && current_page.notify_app_focus_in(event))
                return true;
        
        return (base.focus_in_event != null) ? base.focus_in_event(event) : false;
    }

    public override bool focus_out_event(Gdk.EventFocus event) {
        if (current_page != null && current_page.notify_app_focus_out(event))
                return true;
        
        return (base.focus_out_event != null) ? base.focus_out_event(event) : false;
    }
    
    public override bool configure_event(Gdk.EventConfigure event) {
        if (current_page != null) {
            if (current_page.notify_configure_event(event))
                return true;
        }

        return (base.configure_event != null) ? base.configure_event(event) : false;
    }

    public void set_busy_cursor() {
        if (busy_counter++ > 0)
            return;

        var display = get_window ().get_display ();
        var cursor = new Gdk.Cursor.for_display (display, Gdk.CursorType.WATCH);
        get_window().set_cursor (cursor);
        spin_event_loop();
    }
    
    public void set_normal_cursor() {
        if (busy_counter <= 0) {
            busy_counter = 0;
            return;
        } else if (--busy_counter > 0) {
            return;
        }
        
        var display = get_window ().get_display ();
        var cursor = new Gdk.Cursor.for_display (display, Gdk.CursorType.LEFT_PTR);
        get_window().set_cursor (cursor);
        spin_event_loop();
    }
    
}

// AppWindow is the parent window for most windows in Shotwell (FullscreenWindow is the exception).
// There are multiple types of AppWindows (LibraryWindow, DirectWindow) for different tasks, but only 
// one AppWindow may exist per process.  Thus, if the user closes an AppWindow, the program exits.
//
// AppWindow also offers support for going into fullscreen mode.  It handles the interface
// notifications Page is expecting when switching back and forth.
public abstract class AppWindow : PageWindow {
    public const int DND_ICON_SCALE = 128;
    
    protected static AppWindow instance = null;
    
    private static FullscreenWindow fullscreen_window = null;
    private static CommandManager command_manager = null;
    
    // the AppWindow maintains its own UI manager because the first UIManager an action group is
    // added to is the one that claims its accelerators
    protected bool maximized = false;
    protected Dimensions dimensions;
    protected int pos_x = 0;
    protected int pos_y = 0;
    
    public AppWindow() {
        // although there are multiple AppWindow types, only one may exist per-process
        assert(instance == null);
        instance = this;

        title = Resources.APP_TITLE;
        set_default_icon_name("shotwell");

        // restore previous size and maximization state
        if (this is LibraryWindow) {
            Config.Facade.get_instance().get_library_window_state(out maximized, out dimensions);
        } else {
            assert(this is DirectWindow);
            Config.Facade.get_instance().get_direct_window_state(out maximized, out dimensions);
        }

        set_default_size(dimensions.width, dimensions.height);

        if (maximized)
            maximize();

        assert(command_manager == null);
        command_manager = new CommandManager();
        command_manager.altered.connect(on_command_manager_altered);
        
        // Because the first UIManager to associated with an ActionGroup claims the accelerators,
        // need to create the AppWindow's ActionGroup early on and add it to an application-wide
        // UIManager.  In order to activate those accelerators, we need to create a dummy UI string
        // that lists all the common actions.  We build it on-the-fly from the actions associated
        // with each ActionGroup while we're adding the groups to the UIManager.

        add_actions ();
        
        Gtk.CssProvider provider = new Gtk.CssProvider();
        try {
            provider.load_from_data(Resources.CUSTOM_CSS, -1);
            Gtk.StyleContext.add_provider_for_screen(Gdk.Screen.get_default(), provider, Gtk.STYLE_PROVIDER_PRIORITY_APPLICATION);
        } catch (Error err) {
            debug("Unable to load custom CSS: %s", err.message);
        }
    }

    private const GLib.ActionEntry[] common_actions = {
        { "CommonAbout", on_about },
        { "CommonQuit", on_quit },
        { "CommonFullscreen", on_fullscreen },
        { "CommonHelpContents", on_help_contents },
        { "CommonHelpFAQ", on_help_faq },
        { "CommonHelpReportProblem", on_help_report_problem },
        { "CommonUndo", on_undo },
        { "CommonRedo", on_redo },
        { "CommonJumpToFile", on_jump_to_file },
        { "CommonSelectAll", on_select_all },
        { "CommonSelectNone", on_select_none }
    };

    protected abstract void on_fullscreen();
    
    public static bool has_instance() {
        return instance != null;
    }
    
    public static AppWindow get_instance() {
        return instance;
    }

    public static FullscreenWindow get_fullscreen() {
        return fullscreen_window;
    }

    public static Gtk.Builder create_builder(string glade_filename = "shotwell.ui", void *user = null) {
        Gtk.Builder builder = new Gtk.Builder();
        try {
            builder.add_from_resource(Resources.get_ui(glade_filename));
        } catch(GLib.Error error) {
            warning("Unable to create Gtk.Builder: %s\n", error.message);
        }
        
        builder.connect_signals(user);
        
        return builder;
    }
    
    public static void error_message(string message, Gtk.Window? parent = null) {
        error_message_with_title(Resources.APP_TITLE, message, parent);
    }
    
    public static void error_message_with_title(string title, string message, Gtk.Window? parent = null, bool should_escape = true) {
        // Per the Gnome HIG (http://library.gnome.org/devel/hig-book/2.32/windows-alert.html.en),            
        // alert-style dialogs mustn't have titles; we use the title as the primary text, and the
        // existing message as the secondary text.
        Gtk.MessageDialog dialog = new Gtk.MessageDialog.with_markup((parent != null) ? parent : get_instance(),
            Gtk.DialogFlags.MODAL, Gtk.MessageType.ERROR, Gtk.ButtonsType.OK, "%s", build_alert_body_text(title, message, should_escape));
            
        // Occasionally, with_markup doesn't actually do anything, but set_markup always works.
        dialog.set_markup(build_alert_body_text(title, message, should_escape));

        dialog.use_markup = true;
        dialog.run();
        dialog.destroy();
    }
    
    public static bool negate_affirm_question(string message, string negative, string affirmative,
        string? title = null, Gtk.Window? parent = null) {
        Gtk.MessageDialog dialog = new Gtk.MessageDialog((parent != null) ? parent : get_instance(),
            Gtk.DialogFlags.MODAL, Gtk.MessageType.QUESTION, Gtk.ButtonsType.NONE, "%s", build_alert_body_text(title, message));

        dialog.set_markup(build_alert_body_text(title, message));
        dialog.add_buttons(negative, Gtk.ResponseType.NO, affirmative, Gtk.ResponseType.YES);
        dialog.set_urgency_hint(true);
        
        bool response = (dialog.run() == Gtk.ResponseType.YES);

        dialog.destroy();
        
        return response;
    }

    public static Gtk.ResponseType negate_affirm_cancel_question(string message, string negative,
        string affirmative, string? title = null, Gtk.Window? parent = null) {
        Gtk.MessageDialog dialog = new Gtk.MessageDialog.with_markup((parent != null) ? parent : get_instance(),
            Gtk.DialogFlags.MODAL, Gtk.MessageType.QUESTION, Gtk.ButtonsType.NONE, "%s", build_alert_body_text(title, message));

        dialog.add_buttons(negative, Gtk.ResponseType.NO, affirmative, Gtk.ResponseType.YES,
            _("_Cancel"), Gtk.ResponseType.CANCEL);
        
        // Occasionally, with_markup doesn't actually enable markup, but set_markup always works.
        dialog.set_markup(build_alert_body_text(title, message));
        dialog.use_markup = true;

        int response = dialog.run();
        
        dialog.destroy();
        
        return (Gtk.ResponseType) response;
    }
    
    public static Gtk.ResponseType affirm_cancel_question(string message, string affirmative,
        string? title = null, Gtk.Window? parent = null) {
        Gtk.MessageDialog dialog = new Gtk.MessageDialog.with_markup((parent != null) ? parent : get_instance(),
            Gtk.DialogFlags.MODAL, Gtk.MessageType.QUESTION, Gtk.ButtonsType.NONE, "%s", message);
        // Occasionally, with_markup doesn't actually enable markup...? Force the issue.
        dialog.set_markup(message);
        dialog.use_markup = true;
        dialog.title = (title != null) ? title : Resources.APP_TITLE;
        dialog.add_buttons(affirmative, Gtk.ResponseType.YES, _("_Cancel"),
            Gtk.ResponseType.CANCEL);
        
        int response = dialog.run();
        
        dialog.destroy();
        
        return (Gtk.ResponseType) response;
    }
    
    public static Gtk.ResponseType negate_affirm_all_cancel_question(string message, 
        string negative, string affirmative, string affirmative_all, string? title = null,
        Gtk.Window? parent = null) {
        Gtk.MessageDialog dialog = new Gtk.MessageDialog((parent != null) ? parent : get_instance(),
            Gtk.DialogFlags.MODAL, Gtk.MessageType.QUESTION, Gtk.ButtonsType.NONE, "%s", message);
        dialog.title = (title != null) ? title : Resources.APP_TITLE;
        dialog.add_buttons(negative, Gtk.ResponseType.NO, affirmative, Gtk.ResponseType.YES,
            affirmative_all, Gtk.ResponseType.APPLY,  _("_Cancel"), Gtk.ResponseType.CANCEL);
        
        int response = dialog.run();
        
        dialog.destroy();
        
        return (Gtk.ResponseType) response;
    }
    
    public static void database_error(DatabaseError err) {
        panic(_("A fatal error occurred when accessing Shotwell’s library. Shotwell cannot continue.\n\n%s").printf(
            err.message));
    }
    
    public static void panic(string msg) {
        critical(msg);
        error_message(msg);
        
        Application.get_instance().panic();
    }
    
    public abstract string get_app_role();

    protected void on_about() {
        const string[] artists = { "Aachen logo under public domain license https://www.flickr.com/photos/30784528@N04/10860988196/", null };
        Gtk.show_about_dialog(this,
            // translators: %s will be replaced by application version
            "version", _("%s \u2013 “Aachen”".printf(Resources.APP_VERSION)),
            "comments", get_app_role(),
            "copyright", Resources.COPYRIGHT,
            "website", Resources.HOME_URL,
            "license", Resources.LICENSE,
            "website-label", _("Visit the Shotwell web site"),
            "authors", Resources.AUTHORS,
            "logo", Resources.get_icon(Resources.ICON_ABOUT_LOGO, -1),
            "artists", artists,
            "translator-credits", _("translator-credits"),
            null
        );
    }

    private void on_help_contents() {
        try {
            Resources.launch_help(get_screen());
        } catch (Error err) {
            error_message(_("Unable to display help: %s").printf(err.message));
        }
    }

    private void on_help_report_problem() {
        try {
            show_uri(Resources.BUG_DB_URL);
        } catch (Error err) {
            error_message(_("Unable to navigate to bug database: %s").printf(err.message));
        }
    }
    
    private void on_help_faq() {
        try {
            show_uri(Resources.FAQ_URL);
        } catch (Error err) {
            error_message(_("Unable to display FAQ: %s").printf(err.message));
        }
    }
    
    protected virtual void on_quit() {
        Application.get_instance().exit();
    }

    protected void on_jump_to_file() {
        if (get_current_page().get_view().get_selected_count() != 1)
            return;

        MediaSource? media = get_current_page().get_view().get_selected_at(0).get_source()
            as MediaSource;
        if (media == null)
            return;
        
        try {
           AppWindow.get_instance().show_file_uri(media.get_master_file());
        } catch (Error err) {
            AppWindow.error_message(Resources.jump_to_file_failed(err));
        }
    }
    
    protected override void destroy() {
        on_quit();
    }
    
    public void show_file_uri(File file) throws Error {
        string tmp;
        
        // if file manager is nautilus then pass the full path to file; otherwise pass
        // the enclosing directory
        if(get_nautilus_install_location() != null) {
            tmp = file.get_uri().replace("'","\\\'");
            show_file_in_nautilus(tmp);
        } else {
            tmp = file.get_parent().get_uri().replace("'","\\\'");
            show_uri(tmp);
        }
    }
    
    public void show_uri(string url) throws Error {
        sys_show_uri(get_window().get_screen(), url);
    }
    
    protected virtual void add_actions () {
        this.add_action_entries (AppWindow.common_actions, this);
    }

    public void go_fullscreen(Page page) {
        // if already fullscreen, use that
        if (fullscreen_window != null) {
            fullscreen_window.present();
            
            return;
        }

        get_position(out pos_x, out pos_y);
        hide();
        
        FullscreenWindow fsw = new FullscreenWindow(page);
        
        if (get_current_page() != null)
            get_current_page().switching_to_fullscreen(fsw);
        
        fullscreen_window = fsw;
        fullscreen_window.present();
    }
    
    public void end_fullscreen() {
        if (fullscreen_window == null)
            return;
        
        move(pos_x, pos_y);

        show_all();
        
        if (get_current_page() != null)
            get_current_page().returning_from_fullscreen(fullscreen_window);
        
        fullscreen_window.hide();
        fullscreen_window.destroy();
        fullscreen_window = null;
        
        present();
    }
    
    public GLib.Action? get_common_action(string name) {
        return lookup_action (name);
    }
    
    public void set_common_action_sensitive(string name, bool sensitive) {
        var action = get_common_action(name) as GLib.SimpleAction;
        if (action != null)
            action.set_enabled (sensitive);
    }
    
    public void set_common_action_important(string name, bool important) {
        var action = get_common_action(name) as GLib.SimpleAction;
        if (action != null)
            action.set_enabled (sensitive);
    }
    
    public void set_common_action_visible(string name, bool visible) {
        var action = get_common_action(name) as GLib.SimpleAction;
        if (action != null)
            action.set_enabled (sensitive);
    }
    
    protected override void switched_pages(Page? old_page, Page? new_page) {
        update_common_action_availability(old_page, new_page);
        
        if (old_page != null) {
            old_page.get_view().contents_altered.disconnect(on_update_common_actions);
            old_page.get_view().selection_group_altered.disconnect(on_update_common_actions);
            old_page.get_view().items_state_changed.disconnect(on_update_common_actions);
        }
        
        if (new_page != null) {
            new_page.get_view().contents_altered.connect(on_update_common_actions);
            new_page.get_view().selection_group_altered.connect(on_update_common_actions);
            new_page.get_view().items_state_changed.connect(on_update_common_actions);
            
            update_common_actions(new_page, new_page.get_view().get_selected_count(),
                new_page.get_view().get_count());
        }
        
        base.switched_pages(old_page, new_page);
    }
    
    // This is called when a Page is switched out and certain common actions are simply
    // unavailable for the new one.  This is different than update_common_actions() in that that
    // call is made when state within the Page has changed.
    protected virtual void update_common_action_availability(Page? old_page, Page? new_page) {
        bool is_checkerboard = new_page is CheckerboardPage;
        
        set_common_action_sensitive("CommonSelectAll", is_checkerboard);
        set_common_action_sensitive("CommonSelectNone", is_checkerboard);
    }
    
    // This is a counterpart to Page.update_actions(), but for common Gtk.Actions
    // NOTE: Although CommonFullscreen is declared here, it's implementation is up to the subclasses,
    // therefore they need to update its action.
    protected virtual void update_common_actions(Page page, int selected_count, int count) {
        if (page is CheckerboardPage)
            set_common_action_sensitive("CommonSelectAll", count > 0);
        set_common_action_sensitive("CommonJumpToFile", selected_count == 1);
        
        decorate_undo_action();
        decorate_redo_action();
    }
    
    private void on_update_common_actions() {
        Page? page = get_current_page();
        if (page != null)
            update_common_actions(page, page.get_view().get_selected_count(), page.get_view().get_count());
    }

    public void update_menu_item_label (string id,
                                         string new_label) {
        var bar = this.get_current_page().get_menubar() as GLib.Menu;

        if (bar == null) {
            return;
        }

        var items = bar.get_n_items ();
        for (var i = 0; i< items; i++) {
            var model = bar.get_item_link (i, GLib.Menu.LINK_SUBMENU);
            if (bar == null) {
                continue;
            }

            var model_items = model.get_n_items ();
            for (var j = 0; j < model_items; j++) {
                var subsection = model.get_item_link (j, GLib.Menu.LINK_SECTION);

                if (subsection == null)
                    continue;

                // Recurse into submenus
                var sub_items = subsection.get_n_items ();
                for (var k = 0; k < sub_items; k++) {
                    var it = subsection.iterate_item_attributes (k);
                    while (it.next ()) {
                        if ((it.get_name() == "id" && it.get_value ().get_string () == id) ||
                            (it.get_name() == "action" && it.get_value().get_string().has_suffix("." + id))) {
                            var md = subsection as GLib.Menu;
                            var m = new GLib.MenuItem.from_model (subsection, k);
                            m.set_label (new_label);
                            md.remove (k);
                            md.insert_item (k, m);

                            return;
                        }
                    }
                }
            }
        }
    }


    
    public static CommandManager get_command_manager() {
        return command_manager;
    }
    
    private void on_command_manager_altered() {
        decorate_undo_action();
        decorate_redo_action();
    }
    
    private void decorate_command_manager_action(string name, string prefix,
        string default_explanation, CommandDescription? desc) {
        var action = get_common_action(name) as GLib.SimpleAction;
        if (action == null) {
            return;
        }

        string label = prefix;

        if (desc != null) {
            label += " " + desc.get_name();
            action.set_enabled(true);
        } else {
            label = prefix;
            action.set_enabled(false);
        }
        this.update_menu_item_label(name, label);
    }
    
    public void decorate_undo_action() {
        decorate_command_manager_action("CommonUndo", Resources.UNDO_MENU, "",
            get_command_manager().get_undo_description());
    }
    
    public void decorate_redo_action() {
        decorate_command_manager_action("CommonRedo", Resources.REDO_MENU, "",
            get_command_manager().get_redo_description());
    }
    
    private void on_undo() {
        command_manager.undo();
    }
    
    private void on_redo() {
        command_manager.redo();
    }
    
    private void on_select_all() {
        Page? page = get_current_page() as CheckerboardPage;
        if (page != null)
            page.get_view().select_all();
    }
    
    private void on_select_none() {
        Page? page = get_current_page() as CheckerboardPage;
        if (page != null)
            page.get_view().unselect_all();
    }
    
    public override bool configure_event(Gdk.EventConfigure event) {
        maximized = (get_window().get_state() == Gdk.WindowState.MAXIMIZED);

        if (!maximized)
            get_size(out dimensions.width, out dimensions.height);

        return base.configure_event(event);
    }
    
}