[nautilus/wip/antoniof/gtk4-preparation-step-event-controllers: 7/13] window: Use controller for handling key events

[António Fernandes <antoniof src gnome org>]

commit 134beed7aba42625c334b4fd0b62486abe5fc2b3
Author: António Fernandes <antoniof gnome org>
Date:   Sun Aug 8 16:20:27 2021 +0100

    window: Use controller for handling key events
    
    When overriding the ::key-press-event we are able to do things both
    before and after chaining up in a single funtion.
    
    As the ::event-press-event is going away with GTK4, we are porting to
    event controllers. However, they don't have a chaining up mechanism.
    
    Instead, split the logic into two event controller signal handlers,
    one for "before" (capture phase) and one for "after" (bubble phase).
    This ensures behavior is preserved with relation to accelerators.
    
    Inspired by Ernestas Kulik's earlier port.

 src/nautilus-window.c | 64 +++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 49 insertions(+), 15 deletions(-)
---
diff --git a/src/nautilus-window.c b/src/nautilus-window.c
index 7eed61e79..4d92b384b 100644
--- a/src/nautilus-window.c
+++ b/src/nautilus-window.c
@@ -151,6 +151,8 @@ struct _NautilusWindow
 
     GtkGesture *multi_press_gesture;
     GtkGesture *notebook_multi_press_gesture;
+    GtkEventController *key_capture_controller;
+    GtkEventController *key_bubble_controller;
 };
 
 enum
@@ -2207,6 +2209,9 @@ nautilus_window_dispose (GObject *object)
     g_clear_object (&window->notebook_multi_press_gesture);
     g_clear_object (&window->pad_controller);
 
+    g_clear_object (&window->key_capture_controller);
+    g_clear_object (&window->key_bubble_controller);
+
     G_OBJECT_CLASS (nautilus_window_parent_class)->dispose (object);
 }
 
@@ -2359,33 +2364,49 @@ nautilus_window_realize (GtkWidget *widget)
 }
 
 static gboolean
-nautilus_window_key_press_event (GtkWidget   *widget,
-                                 GdkEventKey *event)
+nautilus_window_key_capture (GtkEventControllerKey *controller,
+                             unsigned int           keyval,
+                             unsigned int           keycode,
+                             GdkModifierType        state,
+                             gpointer               user_data)
 {
-    NautilusWindow *window;
-    guint keyval;
+    g_autoptr (GdkEvent) event = NULL;
+    GtkWidget *widget;
     GtkWidget *focus_widget;
 
-    window = NAUTILUS_WINDOW (widget);
-
-    if (G_UNLIKELY (!gdk_event_get_keyval ((GdkEvent *) event, &keyval)))
-    {
-        g_return_val_if_reached (GDK_EVENT_PROPAGATE);
-    }
-
-    focus_widget = gtk_window_get_focus (GTK_WINDOW (window));
+    event = gtk_get_current_event ();
+    widget = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (controller));
+    focus_widget = gtk_window_get_focus (GTK_WINDOW (widget));
     if (focus_widget != NULL && GTK_IS_EDITABLE (focus_widget))
     {
         /* if we have input focus on a GtkEditable (e.g. a GtkEntry), forward
-         * the event to it before activating accelerator bindings too.
+         * the event to it before activating accelerators. This allows, e.g.,
+         * typing a tilde without activating the prompt-home-location action.
          */
-        if (gtk_window_propagate_key_event (GTK_WINDOW (window),
+        if (gtk_window_propagate_key_event (GTK_WINDOW (widget),
                                             (GdkEventKey *) event))
         {
             return GDK_EVENT_STOP;
         }
     }
 
+    return GDK_EVENT_PROPAGATE;
+}
+
+static gboolean
+nautilus_window_key_bubble (GtkEventControllerKey *controller,
+                            unsigned int           keyval,
+                            unsigned int           keycode,
+                            GdkModifierType        state,
+                            gpointer               user_data)
+{
+    g_autoptr (GdkEvent) event = NULL;
+    GtkWidget *widget;
+    NautilusWindow *window;
+
+    event = gtk_get_current_event ();
+    widget = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (controller));
+    window = NAUTILUS_WINDOW (widget);
     if (window->active_slot != NULL &&
         nautilus_window_slot_handle_event (window->active_slot, (GdkEvent *) event))
     {
@@ -2683,6 +2704,20 @@ nautilus_window_init (NautilusWindow *window)
                                                 GTK_PHASE_CAPTURE);
     gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (window->notebook_multi_press_gesture),
                                    GDK_BUTTON_SECONDARY);
+
+    window->key_capture_controller = gtk_event_controller_key_new (GTK_WIDGET (window));
+    gtk_event_controller_set_propagation_phase (window->key_capture_controller,
+                                                GTK_PHASE_CAPTURE);
+    g_signal_connect (window->key_capture_controller,
+                      "key-pressed", G_CALLBACK (nautilus_window_key_capture),
+                      NULL);
+
+    window->key_bubble_controller = gtk_event_controller_key_new (GTK_WIDGET (window));
+    gtk_event_controller_set_propagation_phase (window->key_bubble_controller,
+                                                GTK_PHASE_BUBBLE);
+    g_signal_connect (window->key_bubble_controller,
+                      "key-pressed", G_CALLBACK (nautilus_window_key_bubble),
+                      NULL);
 }
 
 static void
@@ -2697,7 +2732,6 @@ nautilus_window_class_init (NautilusWindowClass *class)
 
     wclass->show = nautilus_window_show;
     wclass->realize = nautilus_window_realize;
-    wclass->key_press_event = nautilus_window_key_press_event;
     wclass->delete_event = nautilus_window_delete_event;
     wclass->grab_focus = nautilus_window_grab_focus;