toolbar: Handle modal-like entry focus

When the location entry is shown, we remember the previous focus widget
to restore the focus back into it when the location entry is hidden.

This only happens before or after asking the toolbar to show/hide it,
so, we can instead have the toolbar handle this behavior itself.

Replace the setter with explicit open and close methods which handle
the focus. These can also be conveniently used as callbacks.

This way, when the toolbar gets reused in the upcoming FileChooser
window, this behavior will also exist there.

Part of: https://gitlab.gnome.org/GNOME/nautilus/-/work_items/3431

src/nautilus-toolbar.c

@@ -51,6 +51,7 @@ struct _NautilusToolbar
     GtkWidget *search_button_placeholder;
 
     gboolean show_location_entry;
+    GtkWidget *focus_before_location_entry;
 
     GtkWidget *sidebar_button;
     gboolean show_sidebar_button;
@@ -110,11 +111,43 @@ toolbar_update_appearance (NautilusToolbar *self)
                                  search_global ? self->history_controls_placeholder : self->history_controls);
 }
 
-static void
-on_location_entry_close (GtkWidget       *close_button,
-                         NautilusToolbar *self)
+void
+nautilus_toolbar_open_location_entry (NautilusToolbar *self)
 {
-    nautilus_toolbar_set_show_location_entry (self, FALSE);
+    if (self->show_location_entry)
+    {
+        return;
+    }
+
+    /* Remember focus widget. */
+    GtkRoot *root = gtk_widget_get_root (GTK_WIDGET (self));
+    GtkWidget *focus_widget = (root != NULL) ? gtk_root_get_focus (root) : NULL;
+
+    g_set_weak_pointer (&self->focus_before_location_entry, focus_widget);
+
+    self->show_location_entry = TRUE;
+    toolbar_update_appearance (self);
+
+    gtk_widget_grab_focus (self->location_entry);
+}
+
+void
+nautilus_toolbar_close_location_entry (NautilusToolbar *self)
+{
+    if (!self->show_location_entry)
+    {
+        return;
+    }
+
+    self->show_location_entry = FALSE;
+    toolbar_update_appearance (self);
+
+    if (self->focus_before_location_entry != NULL)
+    {
+        /* Restore focus widget. */
+        gtk_widget_grab_focus (self->focus_before_location_entry);
+        g_clear_weak_pointer (&self->focus_before_location_entry);
+    }
 }
 
 static void
@@ -142,7 +175,7 @@ on_location_entry_focus_leave (GtkEventControllerFocus *controller,
         return;
     }
 
-    nautilus_toolbar_set_show_location_entry (toolbar, FALSE);
+    nautilus_toolbar_close_location_entry (toolbar);
 }
 
 static void
@@ -279,6 +312,8 @@ nautilus_toolbar_finalize (GObject *obj)
 {
     NautilusToolbar *self = NAUTILUS_TOOLBAR (obj);
 
+    g_clear_weak_pointer (&self->focus_before_location_entry);
+
     g_signal_handlers_disconnect_by_func (nautilus_preferences,
                                           toolbar_update_appearance, self);
 
@@ -340,7 +375,7 @@ nautilus_toolbar_class_init (NautilusToolbarClass *klass)
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, search_button);
     gtk_widget_class_bind_template_child (widget_class, NautilusToolbar, search_button_placeholder);
 
-    gtk_widget_class_bind_template_callback (widget_class, on_location_entry_close);
+    gtk_widget_class_bind_template_callback (widget_class, nautilus_toolbar_close_location_entry);
 
     gtk_widget_class_set_accessible_role (widget_class, GTK_ACCESSIBLE_ROLE_TOOLBAR);
 }
@@ -364,17 +399,6 @@ nautilus_toolbar_get_location_entry (NautilusToolbar *self)
     return self->location_entry;
 }
 
-void
-nautilus_toolbar_set_show_location_entry (NautilusToolbar *self,
-                                          gboolean         show_location_entry)
-{
-    if (show_location_entry != self->show_location_entry)
-    {
-        self->show_location_entry = show_location_entry;
-        toolbar_update_appearance (self);
-    }
-}
-
 static void
 box_remove_all_children (GtkBox *box)
 {

src/nautilus-toolbar.h

@@ -39,8 +39,8 @@ GtkWidget *nautilus_toolbar_new (void);
 GtkWidget *nautilus_toolbar_get_path_bar (NautilusToolbar *self);
 GtkWidget *nautilus_toolbar_get_location_entry (NautilusToolbar *self);
 
-void       nautilus_toolbar_set_show_location_entry (NautilusToolbar *self,
-                                                     gboolean show_location_entry);
+void       nautilus_toolbar_open_location_entry (NautilusToolbar *self);
+void       nautilus_toolbar_close_location_entry (NautilusToolbar *self);
 
 void       nautilus_toolbar_set_active_slot    (NautilusToolbar    *toolbar,
                                                 NautilusWindowSlot *slot);

src/nautilus-window.c

@@ -120,9 +120,6 @@ struct _NautilusWindow
 
     GtkWidget *network_address_bar;
 
-    /* focus widget before the location bar has been shown temporarily */
-    GtkWidget *last_focus_widget;
-
     guint sidebar_width_handler_id;
     gulong bookmarks_id;
     gulong starred_id;
@@ -631,33 +628,6 @@ nautilus_window_open_location_full (NautilusWindow     *window,
     nautilus_window_slot_open_location_full (target_slot, location, flags, selection);
 }
 
-static void
-unset_focus_widget (NautilusWindow *window)
-{
-    if (window->last_focus_widget != NULL)
-    {
-        g_object_remove_weak_pointer (G_OBJECT (window->last_focus_widget),
-                                      (gpointer *) &window->last_focus_widget);
-        window->last_focus_widget = NULL;
-    }
-}
-
-static void
-remember_focus_widget (NautilusWindow *window)
-{
-    GtkWidget *focus_widget;
-
-    focus_widget = gtk_window_get_focus (GTK_WINDOW (window));
-    if (focus_widget != NULL)
-    {
-        unset_focus_widget (window);
-
-        window->last_focus_widget = focus_widget;
-        g_object_add_weak_pointer (G_OBJECT (focus_widget),
-                                   (gpointer *) &(window->last_focus_widget));
-    }
-}
-
 static gboolean
 nautilus_window_grab_focus (GtkWidget *widget)
 {
@@ -673,23 +643,11 @@ nautilus_window_grab_focus (GtkWidget *widget)
     return GTK_WIDGET_CLASS (nautilus_window_parent_class)->grab_focus (widget);
 }
 
-static void
-restore_focus_widget (NautilusWindow *window)
-{
-    if (window->last_focus_widget != NULL)
-    {
-        gtk_widget_grab_focus (window->last_focus_widget);
-        unset_focus_widget (window);
-    }
-}
-
 static void
 location_entry_cancel_callback (GtkWidget      *widget,
                                 NautilusWindow *window)
 {
-    nautilus_toolbar_set_show_location_entry (NAUTILUS_TOOLBAR (window->toolbar), FALSE);
-
-    restore_focus_widget (window);
+    nautilus_toolbar_close_location_entry (NAUTILUS_TOOLBAR (window->toolbar));
 }
 
 static void
@@ -697,9 +655,7 @@ location_entry_location_changed_callback (GtkWidget      *widget,
                                           GFile          *location,
                                           NautilusWindow *window)
 {
-    nautilus_toolbar_set_show_location_entry (NAUTILUS_TOOLBAR (window->toolbar), FALSE);
-
-    restore_focus_widget (window);
+    nautilus_toolbar_close_location_entry (NAUTILUS_TOOLBAR (window->toolbar));
 
     nautilus_window_open_location_full (window, location, 0, NULL, NULL);
 }
@@ -1080,12 +1036,9 @@ nautilus_window_ensure_location_entry (NautilusWindow *window)
 {
     GtkWidget *location_entry;
 
-    remember_focus_widget (window);
-
-    nautilus_toolbar_set_show_location_entry (NAUTILUS_TOOLBAR (window->toolbar), TRUE);
+    nautilus_toolbar_open_location_entry (NAUTILUS_TOOLBAR (window->toolbar));
 
     location_entry = nautilus_toolbar_get_location_entry (NAUTILUS_TOOLBAR (window->toolbar));
-    gtk_widget_grab_focus (location_entry);
 
     return location_entry;
 }

src/resources/ui/nautilus-toolbar.ui

@@ -39,7 +39,7 @@
                           <object class="GtkButton">
                             <property name="icon-name">window-close-symbolic</property>
                             <property name="tooltip_text" translatable="yes">Cancel</property>
-                            <signal name="clicked" handler="on_location_entry_close"/>
+                            <signal name="clicked" handler="nautilus_toolbar_close_location_entry" swapped="true"/>
                           </object>
                         </child>
                       </object>