Implemended column header mouse clicks.

Ascending/descending sorting.
  Setting the little arrow indicator for ascending
    and desceding sorting.
  Generic stubs.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@41659 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/datavgen.cpp

@@ -617,11 +617,29 @@ void wxDataViewColumn::SetAlignment( wxAlignment WXUNUSED(align) )
     // TODO
 }
 
+void wxDataViewColumn::SetSortable( bool WXUNUSED(sortable) )
+{
+    // TODO
+}
+
+bool wxDataViewColumn::GetSortable()
+{   
+    // TODO
+    return false;
+}
+
 void wxDataViewColumn::SetSortOrder( bool WXUNUSED(ascending) )
 {
     // TODO
 }
 
+bool wxDataViewColumn::IsSortOrderAscending()
+{
+    // TODO
+    return true;
+}
+
+
 wxDataViewColumn::~wxDataViewColumn()
 {
 }