Introduce DocxExport::getBackground()

Does the same as part of DocxExport::WriteMainText() and
DocxExport::WriteSettings().

Change-Id: I5597edc2c3a84bd2058ee8c4cfdc21241e471bd3

sw/source/filter/ww8/docxexport.cxx

@@ -692,10 +692,7 @@ void DocxExport::WriteSettings()
     pFS->singleElementNS(XML_w, XML_zoom, FSNS(XML_w, XML_percent), aZoom.getStr(), FSEND);
 
     // Display Background Shape
-    const SwFrmFmt &rFmt = pDoc->GetPageDesc(0).GetMaster();
-    const SfxPoolItem* pItem = 0;
-    SfxItemState eState = rFmt.GetItemState(RES_BACKGROUND, true, &pItem);
-    if (SFX_ITEM_SET == eState && pItem)
+    if (boost::optional<const SvxBrushItem*> oBrush = getBackground())
     {
         // Turn on the 'displayBackgroundShape'
         pFS->singleElementNS( XML_w, XML_displayBackgroundShape, FSEND );
@@ -738,20 +735,31 @@ VMLExport& DocxExport::VMLExporter()
     return *m_pVMLExport;
 }
 
-void DocxExport::WriteMainText()
+boost::optional<const SvxBrushItem*> DocxExport::getBackground()
 {
-    // setup the namespaces
-    m_pDocumentFS->startElementNS( XML_w, XML_document, MainXmlNamespaces( m_pDocumentFS ));
-
-    // Write background page color
+    boost::optional<const SvxBrushItem*> oRet;
     const SwFrmFmt &rFmt = pDoc->GetPageDesc(0).GetMaster();
     const SfxPoolItem* pItem = 0;
     SfxItemState eState = rFmt.GetItemState(RES_BACKGROUND, true, &pItem);
+
     if (SFX_ITEM_SET == eState && pItem)
     {
         // The 'color' is set for the first page style - take it and use it as the background color of the entire DOCX
         const SvxBrushItem* pBrush = (const SvxBrushItem*)pItem;
-        Color backgroundColor = pBrush->GetColor();
+        oRet.reset(pBrush);
+    }
+    return oRet;
+}
+
+void DocxExport::WriteMainText()
+{
+    // setup the namespaces
+    m_pDocumentFS->startElementNS( XML_w, XML_document, MainXmlNamespaces( m_pDocumentFS ));
+
+    // Write background page color
+    if (boost::optional<const SvxBrushItem*> oBrush = getBackground())
+    {
+        Color backgroundColor = (*oBrush)->GetColor();
         OString aBackgroundColorStr = msfilter::util::ConvertColor(backgroundColor);
 
         m_pDocumentFS->singleElementNS( XML_w, XML_background, FSNS( XML_w, XML_color ), aBackgroundColorStr, FSEND );

sw/source/filter/ww8/docxexport.hxx

@@ -28,6 +28,7 @@
 
 #include <cstdio>
 #include <vector>
+#include <boost/optional.hpp>
 
 class DocxAttributeOutput;
 class DocxExportFilter;
@@ -206,6 +207,9 @@ private:
     /// All xml namespaces to be used at the top of any text .xml file (main doc, headers, footers,...)
     sax_fastparser::XFastAttributeListRef MainXmlNamespaces( sax_fastparser::FSHelperPtr serializer );
 
+    /// Get background color of the document, if there is one.
+    boost::optional<const SvxBrushItem*> getBackground();
+
 public:
     /// FIXME this is temporary, remotely reminding the method of the same
     /// name in WW8Export.