CheckIn:Bug 167201

Before dataset design is saved, the activation of FileSelectionWizardPage must be judged
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.flatfile.ui/src/org/eclipse/datatools/connectivity/oda/flatfile/ui/wizards/FileSelectionWizardPage.java b/plugins/org.eclipse.datatools.connectivity.oda.flatfile.ui/src/org/eclipse/datatools/connectivity/oda/flatfile/ui/wizards/FileSelectionWizardPage.java
index 3738029..ad18c5c 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.flatfile.ui/src/org/eclipse/datatools/connectivity/oda/flatfile/ui/wizards/FileSelectionWizardPage.java
+++ b/plugins/org.eclipse.datatools.connectivity.oda.flatfile.ui/src/org/eclipse/datatools/connectivity/oda/flatfile/ui/wizards/FileSelectionWizardPage.java
@@ -257,6 +257,10 @@
 	 */
 	protected DataSetDesign collectDataSetDesign( DataSetDesign design )
 	{
+		//if this page in DataSetEditor hasn't been activated
+		if ( fileViewer == null )
+			return design;
+		
 		savePage( design );
 		return design;
 	}