[gtk/stack-fixes: 6/7] stack sidebar: Use the selection model

[Matthias Clasen <matthiasc src gnome org>]

commit 0fc5d33bb502ad9f91eae5f06347daa12bf41a31
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Feb 8 18:27:10 2019 -0500

    stack sidebar: Use the selection model
    
    Make GtkStackSidebar and GtkStack communicate via
    the selection model that GtkStack now exposes.
    
    This is parallel to the GtkStackSwitcher changes
    in the previous commit.

 gtk/gtkstacksidebar.c | 241 +++++++++++++++++++++++---------------------------
 1 file changed, 109 insertions(+), 132 deletions(-)
---
diff --git a/gtk/gtkstacksidebar.c b/gtk/gtkstacksidebar.c
index bf1b13759d..77fabd66b2 100644
--- a/gtk/gtkstacksidebar.c
+++ b/gtk/gtkstacksidebar.c
@@ -28,6 +28,7 @@
 #include "gtkscrolledwindow.h"
 #include "gtkseparator.h"
 #include "gtkstylecontext.h"
+#include "gtkselectionmodel.h"
 #include "gtkprivate.h"
 #include "gtkintl.h"
 
@@ -58,8 +59,8 @@ struct _GtkStackSidebarPrivate
 {
   GtkListBox *list;
   GtkStack *stack;
+  GtkSelectionModel *pages;
   GHashTable *rows;
-  gboolean in_child_changed;
 };
 
 G_DEFINE_TYPE_WITH_PRIVATE (GtkStackSidebar, gtk_stack_sidebar, GTK_TYPE_BIN)
@@ -129,30 +130,14 @@ sort_list (GtkListBoxRow *row1,
            GtkListBoxRow *row2,
            gpointer       userdata)
 {
-  GtkStackSidebar *sidebar = GTK_STACK_SIDEBAR (userdata);
-  GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
-  GtkWidget *item;
-  GtkWidget *widget;
   gint left = 0; gint right = 0;
 
 
   if (row1)
-    {
-      item = gtk_bin_get_child (GTK_BIN (row1));
-      widget = g_object_get_data (G_OBJECT (item), "stack-child");
-      g_object_get (gtk_stack_get_page (GTK_STACK (priv->stack), widget),
-                               "position", &left,
-                               NULL);
-    }
+    left = GPOINTER_TO_UINT (g_object_get_data (G_OBJECT (row1), "child-index"));
 
   if (row2)
-    {
-      item = gtk_bin_get_child (GTK_BIN (row2));
-      widget = g_object_get_data (G_OBJECT (item), "stack-child");
-      g_object_get (gtk_stack_get_page (GTK_STACK (priv->stack), widget),
-                               "position", &right,
-                               NULL);
-    }
+    right = GPOINTER_TO_UINT (g_object_get_data (G_OBJECT (row2), "child-index"));
 
   if (left < right)
     return  -1;
@@ -170,18 +155,13 @@ gtk_stack_sidebar_row_selected (GtkListBox    *box,
 {
   GtkStackSidebar *sidebar = GTK_STACK_SIDEBAR (userdata);
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
-  GtkWidget *item;
-  GtkWidget *widget;
+  guint index;
 
-  if (priv->in_child_changed)
+  if (row == NULL)
     return;
 
-  if (!row)
-    return;
-
-  item = gtk_bin_get_child (GTK_BIN (row));
-  widget = g_object_get_data (G_OBJECT (item), "stack-child");
-  gtk_stack_set_visible_child (priv->stack, widget);
+  index = GPOINTER_TO_UINT (g_object_get_data (G_OBJECT (row), "child-index"));
+  gtk_selection_model_select_item (priv->pages, index, TRUE);
 }
 
 static void
@@ -247,174 +227,182 @@ update_row (GtkStackSidebar *sidebar,
 }
 
 static void
-on_position_updated (GtkWidget       *widget,
-                     GParamSpec      *pspec,
-                     GtkStackSidebar *sidebar)
+on_visible_updated (GtkWidget        *widget,
+                    GParamSpec       *pspec,
+                    GtkStackSidebar *sidebar)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
+  GtkWidget *row;
 
-  gtk_list_box_invalidate_sort (priv->list);
+  row = g_hash_table_lookup (priv->rows, widget);
+  update_row (sidebar, widget, row);
 }
 
 static void
-on_child_updated (GtkWidget       *widget,
-                  GParamSpec      *pspec,
-                  GtkStackSidebar *sidebar)
+on_page_updated (GtkStackPage    *page,
+                 GParamSpec      *pspec,
+                 GtkStackSidebar *sidebar)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
+  GtkWidget *widget;
   GtkWidget *row;
 
+  widget = gtk_stack_page_get_child (page);
   row = g_hash_table_lookup (priv->rows, widget);
   update_row (sidebar, widget, row);
 }
 
 static void
-add_child (GtkWidget       *widget,
+add_child (guint            position,
            GtkStackSidebar *sidebar)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
   GtkWidget *item;
   GtkWidget *row;
+  GtkWidget *widget;
   GtkStackPage *page;
 
-  /* Check we don't actually already know about this widget */
-  if (g_hash_table_lookup (priv->rows, widget))
-    return;
-
   /* Make a pretty item when we add kids */
   item = gtk_label_new ("");
   gtk_widget_set_halign (item, GTK_ALIGN_START);
   gtk_widget_set_valign (item, GTK_ALIGN_CENTER);
   row = gtk_list_box_row_new ();
   gtk_container_add (GTK_CONTAINER (row), item);
-  gtk_widget_show (item);
 
+  widget = g_list_model_get_item (G_LIST_MODEL (priv->pages), position);
   update_row (sidebar, widget, row);
 
-  /* Hook up for events */
+  gtk_container_add (GTK_CONTAINER (priv->list), row);
+
+  g_object_set_data (G_OBJECT (row), "child-index", GUINT_TO_POINTER (position));
+  if (gtk_selection_model_is_selected (priv->pages, position))
+    gtk_list_box_select_row (priv->list, GTK_LIST_BOX_ROW (row));
+  else
+    gtk_list_box_unselect_row (priv->list, GTK_LIST_BOX_ROW (row));
+
   page = gtk_stack_get_page (GTK_STACK (priv->stack), widget);
-  g_signal_connect (widget, "notify::visible",
-                    G_CALLBACK (on_child_updated), sidebar);
-  g_signal_connect (page, "notify::title",
-                    G_CALLBACK (on_child_updated), sidebar);
-  g_signal_connect (page, "notify::needs-attention",
-                    G_CALLBACK (on_child_updated), sidebar);
-  g_signal_connect (page, "notify::position",
-                    G_CALLBACK (on_position_updated), sidebar);
-
-  g_object_set_data (G_OBJECT (item), I_("stack-child"), widget);
+  g_signal_connect (widget, "notify::visible", G_CALLBACK (on_visible_updated), sidebar);
+  g_signal_connect (page, "notify", G_CALLBACK (on_page_updated), sidebar);
+
   g_hash_table_insert (priv->rows, widget, row);
-  gtk_container_add (GTK_CONTAINER (priv->list), row);
+
+  g_object_unref (widget);
 }
 
 static void
-remove_child (GtkWidget       *widget,
-              GtkStackSidebar *sidebar)
+populate_sidebar (GtkStackSidebar *sidebar)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
-  GtkWidget *row;
-
-  row = g_hash_table_lookup (priv->rows, widget);
-  if (!row)
-    return;
+  guint i;
 
-  if (priv->stack)
-    {
-      GtkStackPage *page = gtk_stack_get_page (GTK_STACK (priv->stack), widget);
-      if (page)
-        {
-          g_signal_handlers_disconnect_by_func (page, on_child_updated, sidebar);
-          g_signal_handlers_disconnect_by_func (page, on_position_updated, sidebar);
-        }
-    }
-
-  gtk_container_remove (GTK_CONTAINER (priv->list), row);
-  g_hash_table_remove (priv->rows, widget);
+  for (i = 0; i < g_list_model_get_n_items (G_LIST_MODEL (priv->pages)); i++)
+    add_child (i, sidebar);
 }
 
 static void
-populate_sidebar (GtkStackSidebar *sidebar)
+clear_sidebar (GtkStackSidebar *sidebar)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
-  GtkWidget *widget, *row;
-
-  gtk_container_foreach (GTK_CONTAINER (priv->stack), (GtkCallback)add_child, sidebar);
+  GHashTableIter iter;
+  GtkWidget *widget;
+  GtkWidget *row;
 
-  widget = gtk_stack_get_visible_child (priv->stack);
-  if (widget)
+  g_hash_table_iter_init (&iter, priv->rows);
+  while (g_hash_table_iter_next (&iter, (gpointer *)&widget, (gpointer *)&row))
     {
-      row = g_hash_table_lookup (priv->rows, widget);
-      gtk_list_box_select_row (priv->list, GTK_LIST_BOX_ROW (row));
+      gtk_container_remove (GTK_CONTAINER (priv->list), row);
+      g_hash_table_iter_remove (&iter);
+      if (priv->stack)
+        {
+          GtkStackPage *page = gtk_stack_get_page (priv->stack, widget);
+          if (page)
+            g_signal_handlers_disconnect_by_func (page, on_page_updated, sidebar);
+          g_signal_handlers_disconnect_by_func (widget, on_visible_updated, sidebar);
+        }
     }
 }
 
 static void
-clear_sidebar (GtkStackSidebar *sidebar)
+items_changed_cb (GListModel       *model,
+                  guint             position,
+                  guint             removed,
+                  guint             added,
+                  GtkStackSidebar  *sidebar)
 {
-  GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
-
-  gtk_container_foreach (GTK_CONTAINER (priv->stack), (GtkCallback)remove_child, sidebar);
+  /* FIXME: we can do better */
+  clear_sidebar (sidebar);
+  populate_sidebar (sidebar);
 }
 
 static void
-on_child_changed (GtkWidget       *widget,
-                  GParamSpec      *pspec,
-                  GtkStackSidebar *sidebar)
+selection_changed_cb (GtkSelectionModel *model,
+                      guint              position,
+                      guint              n_items,
+                      GtkStackSidebar   *sidebar)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
-  GtkWidget *child;
-  GtkWidget *row;
+  guint i;
 
-  child = gtk_stack_get_visible_child (GTK_STACK (widget));
-  row = g_hash_table_lookup (priv->rows, child);
-  if (row != NULL)
+  for (i = position; i < position + n_items; i++)
     {
-      priv->in_child_changed = TRUE;
-      gtk_list_box_select_row (priv->list, GTK_LIST_BOX_ROW (row));
-      priv->in_child_changed = FALSE;
+      GtkWidget *child;
+      GtkWidget *row;
+
+      child = g_list_model_get_item (G_LIST_MODEL (priv->pages), i);
+      row = g_hash_table_lookup (priv->rows, child);
+      if (gtk_selection_model_is_selected (priv->pages, i))
+        gtk_list_box_select_row (priv->list, GTK_LIST_BOX_ROW (row));
+      else
+        gtk_list_box_unselect_row (priv->list, GTK_LIST_BOX_ROW (row));
+      g_object_unref (child);
     }
 }
 
 static void
-on_stack_child_added (GtkContainer    *container,
-                      GtkWidget       *widget,
-                      GtkStackSidebar *sidebar)
+disconnect_stack_signals (GtkStackSidebar *sidebar)
 {
-  add_child (widget, sidebar);
+  GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
+
+  g_signal_handlers_disconnect_by_func (priv->pages, items_changed_cb, sidebar);
+  g_signal_handlers_disconnect_by_func (priv->pages, selection_changed_cb, sidebar);
 }
 
 static void
-on_stack_child_removed (GtkContainer    *container,
-                        GtkWidget       *widget,
-                        GtkStackSidebar *sidebar)
+connect_stack_signals (GtkStackSidebar *sidebar)
 {
-  remove_child (widget, sidebar);
+  GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
+
+  g_signal_connect (priv->pages, "items-changed", G_CALLBACK (items_changed_cb), sidebar);
+  g_signal_connect (priv->pages, "selection-changed", G_CALLBACK (selection_changed_cb), sidebar);
 }
 
 static void
-disconnect_stack_signals (GtkStackSidebar *sidebar)
+set_stack (GtkStackSidebar *sidebar,
+           GtkStack        *stack)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
 
-  g_signal_handlers_disconnect_by_func (priv->stack, on_stack_child_added, sidebar);
-  g_signal_handlers_disconnect_by_func (priv->stack, on_stack_child_removed, sidebar);
-  g_signal_handlers_disconnect_by_func (priv->stack, on_child_changed, sidebar);
-  g_signal_handlers_disconnect_by_func (priv->stack, disconnect_stack_signals, sidebar);
+  if (stack)
+    {
+      priv->stack = g_object_ref (stack);
+      priv->pages = gtk_stack_get_pages (stack);
+      populate_sidebar (sidebar);
+      connect_stack_signals (sidebar);
+    }
 }
 
 static void
-connect_stack_signals (GtkStackSidebar *sidebar)
+unset_stack (GtkStackSidebar *sidebar)
 {
   GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
 
-  g_signal_connect_after (priv->stack, "add",
-                          G_CALLBACK (on_stack_child_added), sidebar);
-  g_signal_connect_after (priv->stack, "remove",
-                          G_CALLBACK (on_stack_child_removed), sidebar);
-  g_signal_connect (priv->stack, "notify::visible-child",
-                    G_CALLBACK (on_child_changed), sidebar);
-  g_signal_connect_swapped (priv->stack, "destroy",
-                            G_CALLBACK (disconnect_stack_signals), sidebar);
+  if (priv->stack)
+    {
+      disconnect_stack_signals (sidebar);
+      clear_sidebar (sidebar);
+      g_clear_object (&priv->stack);
+      g_clear_object (&priv->pages);
+    }
 }
 
 static void
@@ -422,7 +410,7 @@ gtk_stack_sidebar_dispose (GObject *object)
 {
   GtkStackSidebar *sidebar = GTK_STACK_SIDEBAR (object);
 
-  gtk_stack_sidebar_set_stack (sidebar, NULL);
+  unset_stack (sidebar);
 
   G_OBJECT_CLASS (gtk_stack_sidebar_parent_class)->dispose (object);
 }
@@ -487,28 +475,17 @@ void
 gtk_stack_sidebar_set_stack (GtkStackSidebar *sidebar,
                              GtkStack        *stack)
 {
-  GtkStackSidebarPrivate *priv;
+  GtkStackSidebarPrivate *priv = gtk_stack_sidebar_get_instance_private (sidebar);
 
   g_return_if_fail (GTK_IS_STACK_SIDEBAR (sidebar));
   g_return_if_fail (GTK_IS_STACK (stack) || stack == NULL);
 
-  priv = gtk_stack_sidebar_get_instance_private (sidebar);
 
   if (priv->stack == stack)
     return;
 
-  if (priv->stack)
-    {
-      disconnect_stack_signals (sidebar);
-      clear_sidebar (sidebar);
-      g_clear_object (&priv->stack);
-    }
-  if (stack)
-    {
-      priv->stack = g_object_ref (stack);
-      populate_sidebar (sidebar);
-      connect_stack_signals (sidebar);
-    }
+  unset_stack (sidebar);
+  set_stack (sidebar, stack);
 
   gtk_widget_queue_resize (GTK_WIDGET (sidebar));