added a method in the vectordata provider which returns an index from a field name

git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@5459 c8812cc2-4d05-0410-92ff-de0c093fc19c

Author: mhugent

src/core/qgsvectordataprovider.cpp

@@ -16,6 +16,7 @@
 
 #include "qgsvectordataprovider.h"
 #include "qgsfeature.h"
+#include "qgsfield.h"
 #include "qgssearchtreenode.h"
 
 QgsVectorDataProvider::QgsVectorDataProvider()
@@ -197,3 +198,19 @@ bool QgsVectorDataProvider::setAttributeFilter(const QgsSearchString& attributeF
   // TODO: maybe check if all referenced columns are there, return false if not
   return true;
 }
+
+int QgsVectorDataProvider::indexFromFieldName(const QString& fieldName) const
+{
+  const std::vector<QgsField> theFields = fields();
+  int counter = 0;
+
+  for(std::vector<QgsField>::const_iterator it = theFields.begin(); it != theFields.end(); ++it)
+    {
+      if(it->name() == fieldName)
+	{
+	  return counter;
+	}
+      ++counter;
+    }
+  return -1;
+}

src/core/qgsvectordataprovider.h

@@ -304,6 +304,9 @@ class QgsVectorDataProvider : public QgsDataProvider
        */
       virtual void setWKT(QString wkt){};
 
+      /**Returns the index of a field name or -1 if the field does not exist*/
+      int indexFromFieldName(const QString& fieldName) const;
+
     protected:
       /**Encoding*/
       QTextCodec* mEncoding;

src/gui/qgsvectorlayer.cpp

@@ -3170,6 +3170,7 @@ void QgsVectorLayer::saveAsShapefile()
   dataProvider->saveAsShapefile();
   //  QMessageBox::information(0,"Save As Shapefile", "Someday...");
 }
+
 void QgsVectorLayer::setCoordinateSystem()
 {
   delete mCoordinateTransform;