[glom] libglom::layout_field_should_have_navigation(): Return Relationship not bool.

[Murray Cumming <murrayc src gnome org>]

commit cb515a74e3204ec8744bd96ed7101bc766007383
Author: Murray Cumming <murrayc murrayc com>
Date:   Tue Sep 27 12:05:40 2011 +0200

    libglom::layout_field_should_have_navigation(): Return Relationship not bool.
    
    	* glom/libglom/db_utils.[h|cc]: layout_field_should_have_navigation():
    	Make field_used_in_relationship_to_one() be a Relationship so it can
    	be used for actual navigation.
    	Also require that the LayoutItem_Field has full field information, instead
    	of updating it, so that it can be const.
    	* glom/mode_data/datawidget/datawidget.cc: Constructor: Adapted.
    	* glom/mode_data/box_data_details.cc:
      on_flowtable_field_open_details_requested(): Use it here instead of the
      copy/pasted code.

 ChangeLog                               |   14 ++++++++++++++
 glom/libglom/db_utils.cc                |   11 ++++-------
 glom/libglom/db_utils.h                 |    9 +++++++--
 glom/mode_data/box_data_details.cc      |   22 ++++++++++++++--------
 glom/mode_data/datawidget/datawidget.cc |    6 +++++-
 5 files changed, 44 insertions(+), 18 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 8cc9393..e1119f9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,19 @@
 2011-09-27  Murray Cumming  <murrayc murrayc com>
 
+	libglom::layout_field_should_have_navigation(): Return Relationship not bool.
+
+	* glom/libglom/db_utils.[h|cc]: layout_field_should_have_navigation():
+	Make field_used_in_relationship_to_one() be a Relationship so it can 
+	be used for actual navigation.
+	Also require that the LayoutItem_Field has full field information, instead 
+	of updating it, so that it can be const.
+	* glom/mode_data/datawidget/datawidget.cc: Constructor: Adapted.
+	* glom/mode_data/box_data_details.cc: 
+  on_flowtable_field_open_details_requested(): Use it here instead of the 
+  copy/pasted code.
+
+2011-09-27  Murray Cumming  <murrayc murrayc com>
+
 	Add libglom::layout_field_should_have_navigation().
 
 	* glom/mode_data/datawidget/datawidget.cc: Constructor: Moved decision code
diff --git a/glom/libglom/db_utils.cc b/glom/libglom/db_utils.cc
index 4b89292..2176403 100644
--- a/glom/libglom/db_utils.cc
+++ b/glom/libglom/db_utils.cc
@@ -1624,10 +1624,10 @@ void layout_item_fill_field_details(Document* document, const Glib::ustring& par
   layout_item->set_full_field_details( document->get_field(table_name, layout_item->get_name()) );
 }
 
-bool layout_field_should_have_navigation(const Glib::ustring& table_name, const sharedptr<LayoutItem_Field>& layout_item, const Document* document, bool& field_used_in_relationship_to_one)
+bool layout_field_should_have_navigation(const Glib::ustring& table_name, const sharedptr<const LayoutItem_Field>& layout_item, const Document* document, sharedptr<Relationship>& field_used_in_relationship_to_one)
 {
   //Initialize output parameter:
-  field_used_in_relationship_to_one = false;
+  field_used_in_relationship_to_one = sharedptr<Relationship>();
   
   if(!document)
   {
@@ -1646,16 +1646,13 @@ bool layout_field_should_have_navigation(const Glib::ustring& table_name, const
     std::cerr << G_STRFUNC << ": layout_item was null." << std::endl;
     return false;
   }
-  
-  layout_item->set_full_field_details(
-     document->get_field(layout_item->get_table_used(table_name), layout_item->get_name()) ); //Otherwise get_primary_key() returns false always.
-
 
   //Check whether the field controls a relationship,
   //meaning it identifies a record in another table.
-  field_used_in_relationship_to_one = 
+  sharedptr<const Relationship> const_relationship =
     document->get_field_used_in_relationship_to_one(table_name, layout_item);
   //std::cout << "DEBUG: table_name=" << table_name << ", table_used=" << field->get_table_used(table_name) << ", field=" << field->get_name() << ", field_used_in_relationship_to_one=" << field_used_in_relationship_to_one << std::endl;
+  field_used_in_relationship_to_one = sharedptr<Relationship>::cast_const(const_relationship); //This is just because we can't seem to have a sharedptr<const Relationship>& output parameter.
 
   //Check whether the field identifies a record in another table
   //just because it is a primary key in that table:
diff --git a/glom/libglom/db_utils.h b/glom/libglom/db_utils.h
index 5c013bd..a3439df 100644
--- a/glom/libglom/db_utils.h
+++ b/glom/libglom/db_utils.h
@@ -105,12 +105,17 @@ Gnome::Gda::Value get_next_auto_increment_value(const Glib::ustring& table_name,
 
 void layout_item_fill_field_details(Document* document, const Glib::ustring& parent_table_name, sharedptr<LayoutItem_Field>& layout_item);
 
+
+//TODO: It would be nice to use sharedptr<const Relationship>& instead of sharedptr<Relationship>&,
+//but it does not seem possible to pass a sharedptr<const Relationship> for a sharedptr<const Relationship>&.
+
 /** Decides whether a field should have an Open button next to it,
  * allowing the user to navigate to a related record.
  *
- * @param field_used_in_relationship_to_one Whether the field identifies a single record, so a Find button would also make sense, to choose the ID, in editing mode.
+ * @param layout_item A field on a layout. This must have full field details.
+ * @param field_used_in_relationship_to_one A relationship, if the field identifies a single record, so a Find button would also make sense, to choose the ID, in editing mode.
  */
-bool layout_field_should_have_navigation(const Glib::ustring& table_name, const sharedptr<LayoutItem_Field>& layout_item, const Document* document, bool& field_used_in_relationship_to_one);
+bool layout_field_should_have_navigation(const Glib::ustring& table_name, const sharedptr<const LayoutItem_Field>& layout_item, const Document* document, sharedptr<Relationship>& field_used_in_relationship_to_one);
 
 } //namespace DbUtils
 
diff --git a/glom/mode_data/box_data_details.cc b/glom/mode_data/box_data_details.cc
index b4f578b..8bfb30a 100644
--- a/glom/mode_data/box_data_details.cc
+++ b/glom/mode_data/box_data_details.cc
@@ -642,22 +642,28 @@ void Box_Data_Details::on_flowtable_field_open_details_requested(const sharedptr
   if(Conversions::value_is_empty(field_value))
     return; //Ignore empty ID fields.
 
+  //Updating doesn't seem necessary. The field details seem to be full already.
+  //Update the field details from the document:
+  ////sharedptr<LayoutItem_Field> unconst_field = sharedptr<LayoutItem_Field>::cast_const(layout_field); //A hack, because layout_field_should_have_navigation() needs to get full field details.
+  //unconst_field->set_full_field_details(
+  //  document->get_field(field->get_table_used(table_name), field->get_name()) ); //Otherwise get_primary_key() returns false always.
+      
+  sharedptr<Relationship> field_used_in_relationship_to_one;
+  const bool has_open_button = 
+    DbUtils::layout_field_should_have_navigation(m_table_name, layout_field, get_document(), 
+    field_used_in_relationship_to_one);
+         
   //If it's a simple field that is part of a relationship,
   //identifying a related record.
-  sharedptr<const Relationship> relationship = get_document()->get_field_used_in_relationship_to_one(m_table_name, layout_field);
-  if(relationship)
+  if(field_used_in_relationship_to_one)
   {
-    signal_requested_related_details().emit(relationship->get_to_table(), field_value);
+    signal_requested_related_details().emit(field_used_in_relationship_to_one->get_to_table(), field_value);
     return;
   }
 
   //If it is a related field that is a primary key,
   //meaning it identifies a record in another table:
-  sharedptr<const Field> field_info = layout_field->get_full_field_details();
-  const bool field_is_related_primary_key =
-    layout_field->get_has_relationship_name() &&
-    field_info && field_info->get_primary_key();
-  if(field_is_related_primary_key)
+  if(has_open_button)
   {
     signal_requested_related_details().emit(layout_field->get_table_used(m_table_name), field_value);
   }
diff --git a/glom/mode_data/datawidget/datawidget.cc b/glom/mode_data/datawidget/datawidget.cc
index 839df6a..4b13036 100644
--- a/glom/mode_data/datawidget/datawidget.cc
+++ b/glom/mode_data/datawidget/datawidget.cc
@@ -176,7 +176,11 @@ DataWidget::DataWidget(const sharedptr<LayoutItem_Field>& field, const Glib::ust
 
     bool child_added = false; //Don't use an extra container unless necessary.
 
-    bool field_used_in_relationship_to_one = false;
+    //Update the field details from the document:
+    field->set_full_field_details(
+      document->get_field(field->get_table_used(table_name), field->get_name()) ); //Otherwise get_primary_key() returns false always.
+
+    sharedptr<Relationship> field_used_in_relationship_to_one;
     const bool add_open_button = 
        DbUtils::layout_field_should_have_navigation(table_name, field, document, 
          field_used_in_relationship_to_one);