[glom] Print Layout: Cache the selected item.

[Murray Cumming <murrayc src gnome org>]

commit cd70cae1baa83903e17e94b94e1298595e04900c
Author: Murray Cumming <murrayc murrayc com>
Date:   Sat Aug 6 14:15:19 2011 +0200

    Print Layout: Cache the selected item.
    
    * glom/mode_design/print_layouts/window_print_layout_edit.[h|cc]:
    Store the selected item, when it changes, instead of repeatedly
    requesting it, which requires iteration.

 ChangeLog                                          |    8 +++
 .../print_layouts/window_print_layout_edit.cc      |   49 +++++++-------------
 .../print_layouts/window_print_layout_edit.h       |    5 ++
 3 files changed, 30 insertions(+), 32 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index faba16b..608b675 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2011-08-06  Murray Cumming  <murrayc murrayc com>
 
+	Print Layout: Cache the selected item.
+
+	* glom/mode_design/print_layouts/window_print_layout_edit.[h|cc]:
+	Store the selected item, when it changes, instead of repeatedly 
+	requesting it, which requires iteration.
+
+2011-08-06  Murray Cumming  <murrayc murrayc com>
+
 	Print Layout: Allow editing of positions and size numerically,
 
 	* ui/developer/window_print_layout_edit.glade: Add a row of SpinButtons
diff --git a/glom/mode_design/print_layouts/window_print_layout_edit.cc b/glom/mode_design/print_layouts/window_print_layout_edit.cc
index 8d12363..66dd309 100644
--- a/glom/mode_design/print_layouts/window_print_layout_edit.cc
+++ b/glom/mode_design/print_layouts/window_print_layout_edit.cc
@@ -990,80 +990,65 @@ void Window_PrintLayout_Edit::on_canvas_selection_changed()
   //TODO: Let the user resize groups of items.
   const bool enable = (items.size() == 1);
   m_box_item_position->set_sensitive(enable);
+
+  if(enable)
+    m_layout_item_selected = items[0];
+  else
+    m_layout_item_selected.reset();
 }
 
 void Window_PrintLayout_Edit::on_spinbutton_x()
 {
-  Canvas_PrintLayout::type_vec_items items = m_canvas.get_selected_items();
-  if(items.empty())
-    return;
-
-  Glib::RefPtr<CanvasLayoutItem> item = items[0];
-  if(!item)
+  if(!m_layout_item_selected)
     return;
 
   double x = 0;
   double y = 0;
-  item->get_xy(x, y);
+  m_layout_item_selected->get_xy(x, y);
 
-  item->set_xy(
+  m_layout_item_selected->set_xy(
     m_spinbutton_x->get_value(),
     y);
 }
 
 void Window_PrintLayout_Edit::on_spinbutton_y()
 {
-  Canvas_PrintLayout::type_vec_items items = m_canvas.get_selected_items();
-  if(items.empty())
-    return;
-
-  Glib::RefPtr<CanvasLayoutItem> item = items[0];
-  if(!item)
+  if(!m_layout_item_selected)
     return;
 
   double x = 0;
   double y = 0;
-  item->get_xy(x, y);
+  m_layout_item_selected->get_xy(x, y);
 
-  item->set_xy(
+  m_layout_item_selected->set_xy(
     x,
     m_spinbutton_y->get_value());
 }
 
 void Window_PrintLayout_Edit::on_spinbutton_width()
 {
-  Canvas_PrintLayout::type_vec_items items = m_canvas.get_selected_items();
-  if(items.empty())
-    return;
-
-  Glib::RefPtr<CanvasLayoutItem> item = items[0];
-  if(!item)
+  if(!m_layout_item_selected)
     return;
 
   double width = 0;
   double height = 0;
-  item->get_width_height(width, height);
+  m_layout_item_selected->get_width_height(width, height);
 
-  item->set_width_height(
+  m_layout_item_selected->set_width_height(
     m_spinbutton_width->get_value(),
     height);
 }
 
 void Window_PrintLayout_Edit::on_spinbutton_height()
 {
-  Canvas_PrintLayout::type_vec_items items = m_canvas.get_selected_items();
-  if(items.empty())
-    return;
-
-  Glib::RefPtr<CanvasLayoutItem> item = items[0];
-  if(!item)
+  if(!m_layout_item_selected)
     return;
 
   double width = 0;
   double height = 0;
-  item->get_width_height(width, height);
+  m_layout_item_selected->get_width_height(width, height);
 
-  item->set_width_height(
+  m_layout_item_selected->set_width_height(
     width,
     m_spinbutton_height->get_value());
 }
diff --git a/glom/mode_design/print_layouts/window_print_layout_edit.h b/glom/mode_design/print_layouts/window_print_layout_edit.h
index 9284971..d5fad86 100644
--- a/glom/mode_design/print_layouts/window_print_layout_edit.h
+++ b/glom/mode_design/print_layouts/window_print_layout_edit.h
@@ -140,6 +140,10 @@ private:
   bool m_drag_preview_requested;
   Glib::RefPtr<CanvasLayoutItem> m_layout_item_dropping;
 
+  //A cache of the selected item,
+  //to avoid repeatedly requesting it:
+  Glib::RefPtr<CanvasLayoutItem> m_layout_item_selected;
+
   GimpRuler* m_vruler;
   GimpRuler* m_hruler;
 
@@ -158,6 +162,7 @@ private:
   Gtk::Menu* m_context_menu;
   Glib::RefPtr<Gtk::ActionGroup> m_context_menu_action_group;
   Glib::RefPtr<Gtk::UIManager> m_context_menu_uimanager;
+
 };
 
 } //namespace Glom