[gnumeric] xlsx: better backplane handling.

[Morten Welinder <mortenw src gnome org>]

commit 646b53a2f27a2b35b98b95dde7046e0c12169396
Author: Morten Welinder <terra gnome org>
Date:   Sun Apr 5 14:12:05 2015 -0400

    xlsx: better backplane handling.

 plugins/excel/ChangeLog           |    5 ++++
 plugins/excel/xlsx-read-drawing.c |   42 ++++++++++++++++++------------------
 2 files changed, 26 insertions(+), 21 deletions(-)
---
diff --git a/plugins/excel/ChangeLog b/plugins/excel/ChangeLog
index 328754b..be35e2c 100644
--- a/plugins/excel/ChangeLog
+++ b/plugins/excel/ChangeLog
@@ -1,3 +1,8 @@
+2015-04-05  Morten Welinder  <terra gnome org>
+
+       * xlsx-read-drawing.c (xlsx_chart_add_plot): Add backplane here.
+       (xlsx_plot_area): Not here, but push a dummy object.
+
 2015-04-04  Morten Welinder  <terra gnome org>
 
        * xlsx-read-drawing.c (xlsx_plot_area_end): Get rid of the
diff --git a/plugins/excel/xlsx-read-drawing.c b/plugins/excel/xlsx-read-drawing.c
index 9504448..3e95de7 100644
--- a/plugins/excel/xlsx-read-drawing.c
+++ b/plugins/excel/xlsx-read-drawing.c
@@ -615,10 +615,28 @@ static void
 xlsx_chart_add_plot (GsfXMLIn *xin, char const *type)
 {
        XLSXReadState *state = (XLSXReadState *)xin->user_state;
-       if (NULL != (state->plot = (GogPlot*) gog_plot_new_by_name (type)))
+       if (NULL != (state->plot = (GogPlot*) gog_plot_new_by_name (type))) {
                /* Add _before_ setting styles so theme does not override */
                gog_object_add_by_name (GOG_OBJECT (state->chart),
                        "Plot", GOG_OBJECT (state->plot));
+
+               if (state->cur_obj == NULL) {
+                       /* Add a backplane if compatible with plot.  */
+
+                       const char *bp_name = "Backplane";
+                       GogObjectRole const *role =
+                               gog_object_find_role_by_name (GOG_OBJECT (state->chart),
+                                                             bp_name);
+                       if (role->can_add (GOG_OBJECT (state->chart))) {
+                               GogObject *bp = gog_object_add_by_name (GOG_OBJECT (state->chart),
+                                                                       bp_name,
+                                                                       NULL);
+                               /* Replace dummy object.  */
+                               xlsx_chart_pop_obj (state);
+                               xlsx_chart_push_obj (state, bp);
+                       }
+               }
+       }
 }
 
 /* shared with pie of pie, and bar of pie */
@@ -2086,33 +2104,15 @@ static void
 xlsx_plot_area (GsfXMLIn *xin, G_GNUC_UNUSED xmlChar const **attrs)
 {
        XLSXReadState *state = (XLSXReadState *)xin->user_state;
-       GogObject *backplane = gog_object_add_by_name (
-               GOG_OBJECT (state->chart), "Backplane", NULL);
-       xlsx_chart_push_obj (state, backplane);
+       /* Push a NULL object for backplane.  */
+       xlsx_chart_push_obj (state, NULL);
 }
 
 static void
 xlsx_plot_area_end (GsfXMLIn *xin, G_GNUC_UNUSED GsfXMLBlob *blob)
 {
        XLSXReadState *state = (XLSXReadState *)xin->user_state;
-       GogObject *bp = g_object_ref (state->cur_obj);
-       gboolean remove_backplane;
-
        xlsx_chart_pop_obj (state);
-
-       /*
-        * We added a backplane.  For pie and ring charts we don't need it.
-        * We might want to see if we can wait and only add it for plots
-        * that need it.
-        */
-       remove_backplane =
-               gog_chart_axis_set_is_valid (state->chart, GOG_AXIS_SET_NONE);
-       if (remove_backplane) {
-               gog_object_clear_parent (bp);
-               g_object_unref (bp);
-       }
-
-       g_object_unref (bp);
 }