[balsa/gtk3] Scroll on open in an idle handler

[Peter Bloomfield <PeterB src gnome org>]

commit c6cf9de8cbfd95b0fa9e158d62caf63f814dd0ba
Author: Peter Bloomfield <PeterBloomfield bellsouth net>
Date:   Mon Apr 22 19:26:59 2013 -0400

    Scroll on open in an idle handler
    
        * src/balsa-index.c (bndx_scroll_on_open_idle),
        (balsa_index_scroll_on_open): scroll in an idle handler, after
        the mailbox has been opened.

 ChangeLog         |  6 ++++
 src/balsa-index.c | 91 ++++++++++++++++++++++---------------------------------
 2 files changed, 43 insertions(+), 54 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index b7e5861..f7b55bf 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2013-04-22  Peter Bloomfield
+
+       * src/balsa-index.c (bndx_scroll_on_open_idle),
+       (balsa_index_scroll_on_open): scroll in an idle handler, after
+       the mailbox has been opened.
+
 2013-04-16  Peter Bloomfield
 
        * libbalsa/address-view.c (lbav_drop_down_activated_cb),
diff --git a/src/balsa-index.c b/src/balsa-index.c
index a83920e..2453754 100644
--- a/src/balsa-index.c
+++ b/src/balsa-index.c
@@ -808,58 +808,25 @@ balsa_index_new(void)
  * thread only. And we also check whether the mailbox hasn't been
  * destroyed by now, of course.
  */
-struct view_on_open_data {
-    BalsaIndex *bindex;
-    GtkTreeRowReference *reference;
-    gboolean select;
-};
 
 static gboolean
-bi_view_on_open(struct view_on_open_data *data)
-{
-    GtkTreeView *tree_view;
-    GtkTreePath *path;
-
-    tree_view = GTK_TREE_VIEW(data->bindex);
-    path = gtk_tree_row_reference_get_path(data->reference);
-    gtk_tree_row_reference_free(data->reference);
-
-    if (gtk_tree_view_get_model(tree_view)) {
-        if (data->select)
-            bndx_select_row(data->bindex, path);
-        else {
-            GtkTreeSelection *selection;
-            gulong changed_id = data->bindex->selection_changed_id;
-
-            selection = gtk_tree_view_get_selection(tree_view);
-            g_signal_handler_block(selection, changed_id);
-            gtk_tree_view_set_cursor(tree_view, path, NULL, FALSE);
-            gtk_tree_selection_unselect_all(selection);
-            g_signal_handler_unblock(selection, changed_id);
-        }
-    }
-    gtk_tree_path_free(path);
-    g_object_unref(data->bindex);
-    g_free(data);
-
-    return FALSE;
-}
-
-void
-balsa_index_scroll_on_open(BalsaIndex *index)
+bndx_scroll_on_open_idle(BalsaIndex *index)
 {
-    LibBalsaMailbox *mailbox = index->mailbox_node->mailbox;
+    LibBalsaMailbox *mailbox;
     GtkTreeView *tree_view = GTK_TREE_VIEW(index);
-    GtkTreePath *path = NULL;
+    GtkTreePath *path;
     gpointer view_on_open;
-    struct view_on_open_data *data;
+
+    if (bndx_clear_if_last_ref(&index))
+        return FALSE;
 
     balsa_index_update_tree(index, balsa_app.expand_tree);
+    mailbox = index->mailbox_node->mailbox;
     if (mailbox->first_unread) {
        unsigned msgno = mailbox->first_unread;
        mailbox->first_unread = 0;
         if(!libbalsa_mailbox_msgno_find(mailbox, msgno, &path, NULL))
-            return; /* Oops! */
+            return FALSE; /* Oops! */
     } else {
         /* we want to scroll to the last one in current order. The
            alternative which is to scroll to the most recently
@@ -868,28 +835,44 @@ balsa_index_scroll_on_open(BalsaIndex *index)
         int total = gtk_tree_model_iter_n_children
             (GTK_TREE_MODEL(mailbox), NULL);
         if(total == 0)
-            return;
+            return FALSE;
         path = gtk_tree_path_new_from_indices(total - 1, -1);
     }
 
     bndx_expand_to_row(index, path);
-    /* Scroll now, not in the idle handler, to make sure the initial
-     * view is correct. */
     gtk_tree_view_scroll_to_cell(tree_view, path, NULL, FALSE, 0, 0);
 
     view_on_open =
         g_object_get_data(G_OBJECT(mailbox), BALSA_INDEX_VIEW_ON_OPEN);
-    g_object_set_data(G_OBJECT(mailbox),
-                      BALSA_INDEX_VIEW_ON_OPEN,
-                      GINT_TO_POINTER(FALSE));
-    data = g_new(struct view_on_open_data,1);
-    data->bindex = g_object_ref(index);
-    data->reference =
-        gtk_tree_row_reference_new(GTK_TREE_MODEL(mailbox), path);
+    g_object_set_data(G_OBJECT(mailbox), BALSA_INDEX_VIEW_ON_OPEN, NULL);
+
+    if (gtk_tree_view_get_model(tree_view)) {
+        if ((view_on_open && GPOINTER_TO_INT(view_on_open))
+            || balsa_app.view_message_on_open)
+            bndx_select_row(index, path);
+        else {
+            GtkTreeSelection *selection;
+            gulong changed_id = index->selection_changed_id;
+
+            selection = gtk_tree_view_get_selection(tree_view);
+            g_signal_handler_block(selection, changed_id);
+            gtk_tree_view_set_cursor(tree_view, path, NULL, FALSE);
+            gtk_tree_selection_unselect_all(selection);
+            g_signal_handler_unblock(selection, changed_id);
+        }
+    }
     gtk_tree_path_free(path);
-    data->select = (view_on_open && GPOINTER_TO_INT(view_on_open))
-        || balsa_app.view_message_on_open;
-    g_idle_add((GSourceFunc)bi_view_on_open, data);
+
+    return FALSE;
+}
+
+void
+balsa_index_scroll_on_open(BalsaIndex * bindex)
+{
+    /* Scroll in an idle handler, because the mailbox is perhaps being
+     * opened in its own idle handler. */
+    g_idle_add((GSourceFunc) bndx_scroll_on_open_idle,
+               g_object_ref(bindex));
 }
 
 static LibBalsaCondition *cond_undeleted;