[glom] Clean up the code to load/save portal navigation options.

[Murray Cumming <murrayc src gnome org>]

commit a25beff23fa5850a0d5aeb8f1b15ae1df8111a6d
Author: Murray Cumming <murrayc murrayc com>
Date:   Thu Jun 4 16:35:38 2009 +0200

    Clean up the code to load/save portal navigation options.
    
    * glom/libglom/document/document.cc: load_after_layout_group():
    Loading the portal's navigation options: Use == instead of
    ustring::compare() because this is not C.
    Explicitly default to automatic, removing the comment about defaulting
    to the default in the Portal's class to preserve the deprecated file
    format. This is more obvious.
    save_before_layout_group(): Simplify the code.
    Do not write GLOM_ATTRIBUTE_PORTAL_NAVIGATIONRELATIONSHIP_MAIN because
    a) It is deprecated (should be read but not written) and b) It is not
    read or used anywhere else anyway.
    Use constants for the possible attribute values, instead of copy/pasting
    the same string constants in several places.
---
 ChangeLog                         |   17 ++++++++++
 glom/libglom/document/document.cc |   60 ++++++++++++++++++++----------------
 2 files changed, 50 insertions(+), 27 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 4c483d1..178d3b8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,22 @@
 2009-06-04  Murray Cumming  <murrayc murrayc-x61>
 
+	Clean up the code to load/save portal navigation options.
+
+	* glom/libglom/document/document.cc: load_after_layout_group(): 
+	Loading the portal's navigation options: Use == instead of 
+	ustring::compare() because this is not C.
+	Explicitly default to automatic, removing the comment about defaulting 
+	to the default in the Portal's class to preserve the deprecated file 
+	format. This is more obvious.
+	save_before_layout_group(): Simplify the code.
+	Do not write GLOM_ATTRIBUTE_PORTAL_NAVIGATIONRELATIONSHIP_MAIN because 
+	a) It is deprecated (should be read but not written) and b) It is not 
+	read or used anywhere else anyway.
+	Use constants for the possible attribute values, instead of copy/pasting 
+	the same string constants in several places.
+
+2009-06-04  Murray Cumming  <murrayc murrayc-x61>
+
 	Store script module code in child text nodes.
 
 	* glom/libglom/document/document.cc: load_after(), save_before(): 
diff --git a/glom/libglom/document/document.cc b/glom/libglom/document/document.cc
index a0ddcf8..c9dda05 100644
--- a/glom/libglom/document/document.cc
+++ b/glom/libglom/document/document.cc
@@ -71,10 +71,14 @@ namespace Glom
 #define GLOM_ATTRIBUTE_PARENT_TABLE_NAME "parent_table"
 
 #define GLOM_NODE_DATA_LAYOUT_NOTEBOOK "data_layout_notebook"
+
 #define GLOM_NODE_DATA_LAYOUT_PORTAL "data_layout_portal"
 #define GLOM_NODE_DATA_LAYOUT_PORTAL_NAVIGATIONRELATIONSHIP "portal_navigation_relationship"
-#define GLOM_ATTRIBUTE_PORTAL_NAVIGATIONRELATIONSHIP_MAIN "navigation_main"
 #define GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE "navigation_type"
+#define GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_AUTOMATIC "automatic"
+#define GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_SPECIFIC "specific"
+#define GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_NONE "none"
+
 #define GLOM_NODE_DATA_LAYOUT_CALENDAR_PORTAL "data_layout_calendar_portal"
 #define GLOM_ATTRIBUTE_PORTAL_PRINT_LAYOUT_ROW_HEIGHT "row_height"
 #define GLOM_ATTRIBUTE_PORTAL_CALENDAR_DATE_FIELD "date_field"
@@ -2174,22 +2178,21 @@ void Document::load_after_layout_group(const xmlpp::Element* node, const Glib::u
         xmlpp::Element* elementNavigationRelationshipSpecific = get_node_child_named(element, GLOM_NODE_DATA_LAYOUT_PORTAL_NAVIGATIONRELATIONSHIP);
         if(elementNavigationRelationshipSpecific)
         {
-          const Glib::ustring navigation_type_as_string = get_node_attribute_value(elementNavigationRelationshipSpecific, GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE);
-          // If no GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE was found, or if the
-          // string it contains could not be mapped then we stick with the
-          // portal class' default for its navigation_type member,
-          // LayoutItem_Portal::NAVIGATION_AUTOMATIC. This keeps us
-          // read-compatible with older versions of Glom files.
-          if(0 == navigation_type_as_string.compare("automatic"))
+          const Glib::ustring navigation_type_as_string = 
+            get_node_attribute_value(elementNavigationRelationshipSpecific, 
+            GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE);
+          if(navigation_type_as_string.empty() || 
+             navigation_type_as_string == GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_AUTOMATIC)
           {
             portal->set_navigation_type(LayoutItem_Portal::NAVIGATION_AUTOMATIC);
           }
-          else if(0 == navigation_type_as_string.compare("none"))
+          else if(navigation_type_as_string == GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_NONE)
           {
             portal->set_navigation_type(LayoutItem_Portal::NAVIGATION_NONE);
           }
-          else if(0 == navigation_type_as_string.compare("specific"))
+          else if(navigation_type_as_string == GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_SPECIFIC)
           {
+            //Read the specified relationship name:
             sharedptr<UsesRelationship>relationship_navigation_specific = sharedptr<UsesRelationship>::create();
             load_after_layout_item_usesrelationship(elementNavigationRelationshipSpecific, portal->get_table_used(table_name), relationship_navigation_specific);
             portal->set_navigation_relationship_specific(relationship_navigation_specific);
@@ -3041,25 +3044,28 @@ void Document::save_before_layout_group(xmlpp::Element* node, const sharedptr<co
 
               //Portal navigation details:
               xmlpp::Element* child_navigation_relationship = child->add_child(GLOM_NODE_DATA_LAYOUT_PORTAL_NAVIGATIONRELATIONSHIP);
-              if(portal->get_navigation_type() == LayoutItem_Portal::NAVIGATION_AUTOMATIC)
-              {
-                sharedptr<const UsesRelationship> relationship_navigation_none;
-                save_before_layout_item_usesrelationship(child_navigation_relationship, relationship_navigation_none);
-                set_node_attribute_value(child_navigation_relationship, GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE, "automatic");
-              }
-              else if(portal->get_navigation_type() == LayoutItem_Portal::NAVIGATION_NONE)
-              {
-                sharedptr<const UsesRelationship> relationship_navigation_none;
-                save_before_layout_item_usesrelationship(child_navigation_relationship, relationship_navigation_none);
-                set_node_attribute_value(child_navigation_relationship, GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE, "none");
-              }
-              else if(portal->get_navigation_type() == LayoutItem_Portal::NAVIGATION_SPECIFIC)
+
+              Glib::ustring navigation_type_string = GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_AUTOMATIC; //Default.
+              sharedptr<const UsesRelationship> relationship_navigation_specific;
+
+              switch(portal->get_navigation_type())
               {
-                sharedptr<const UsesRelationship> relationship_navigation_specific = portal->get_navigation_relationship_specific();
-                save_before_layout_item_usesrelationship(child_navigation_relationship, relationship_navigation_specific);
-                set_node_attribute_value_as_bool(child_navigation_relationship, GLOM_ATTRIBUTE_PORTAL_NAVIGATIONRELATIONSHIP_MAIN, false);
-                set_node_attribute_value(child_navigation_relationship, GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE, "specific");
+                case LayoutItem_Portal::NAVIGATION_AUTOMATIC:
+                  navigation_type_string = GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_AUTOMATIC;
+                  break;
+                case LayoutItem_Portal::NAVIGATION_NONE:
+                  navigation_type_string = GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_NONE;
+                  break;
+                case LayoutItem_Portal::NAVIGATION_SPECIFIC:
+                  navigation_type_string = GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE_SPECIFIC;
+                  break;
+                default:
+                  break;
               }
+   
+              save_before_layout_item_usesrelationship(child_navigation_relationship, relationship_navigation_specific);
+              set_node_attribute_value(child_navigation_relationship, 
+                GLOM_ATTRIBUTE_PORTAL_NAVIGATION_TYPE, navigation_type_string);
 
               //Print Layout specific stuff:
               set_node_attribute_value_as_decimal(child, GLOM_ATTRIBUTE_PORTAL_PRINT_LAYOUT_ROW_HEIGHT, portal->get_print_layout_row_height());