rebuild all serialization to use string concatenation instead of nokogiri.

1 files changed, 12 insertions, 15 deletions

diff --git a/lib/axlsx/drawing/series_title.rb b/lib/axlsx/drawing/series_title.rb
index b13cec89..39ec10d5 100644
--- a/lib/axlsx/drawing/series_title.rb
+++ b/lib/axlsx/drawing/series_title.rb
@@ -3,21 +3,18 @@ module Axlsx
   # A series title is a Title with a slightly different serialization than chart titles.
   class SeriesTitle < Title
 
-    # Serializes the series title
-    # @param [Nokogiri::XML::Builder] xml The document builder instance this objects xml will be added to.
-    # @return [String]
-    def to_xml(xml)
-      xml[:c].tx {
-        xml[:c].strRef {
-          xml[:c].f Axlsx::cell_range([@cell])
-          xml[:c].strCache {
-            xml[:c].ptCount :val=>1
-            xml[:c].pt(:idx=>0) {
-              xml[:c].v @text
-            }
-          }
-        }
-      }
+    def to_xml_string(str = '')
+      str << '<c:tx>'
+      str << '<c:strRef>'
+      str << '<c:f>' << Axlsx::cell_range([@cell]) << '</c:f>'
+      str << '<c:strCache>'
+      str << '<c:ptCount val="1"/>'
+      str << '<c:pt idx="0">'
+      str << '<c:v>' << @text << '</c:v>'
+      str << '</c:pt>'
+      str << '</c:strCache>'
+      str << '</c:strRef>'
+      str << '</c:tx>'
     end
   end
 end