X-Git-Url: http://source.jalview.org/gitweb/?p=jalview.git;a=blobdiff_plain;f=src%2Fjalview%2Fdatamodel%2FAlignment.java;h=0f51b7e538b9c3c25e7d397f7df51fb21d072e61;hp=11d28a007df16faaf6f7d9366e7fb523a788fe26;hb=985fd5ff517f3eb5221a7aefec88138341514779;hpb=92c2fd083f7f5844693878f946441d75241f13bb

diff --git a/src/jalview/datamodel/Alignment.java b/src/jalview/datamodel/Alignment.java
index 11d28a0..0f51b7e 100755
--- a/src/jalview/datamodel/Alignment.java
+++ b/src/jalview/datamodel/Alignment.java
@@ -1908,9 +1908,12 @@ public class Alignment implements AlignmentI
   }
 
   @Override
-  public void setHiddenColumns(HiddenColumns cols)
+  public boolean setHiddenColumns(HiddenColumns cols)
   {
+    boolean changed = cols == null ? hiddenCols != null
+            : !cols.equals(hiddenCols);
     hiddenCols = cols;
+    return changed;
   }
 
   @Override