sg might be null if mouse released after coloumns removed

diff --git a/src/jalview/gui/ScalePanel.java b/src/jalview/gui/ScalePanel.java
index 7ed0146..99b8620 100755 (executable)
--- a/src/jalview/gui/ScalePanel.java
+++ b/src/jalview/gui/ScalePanel.java
@@ -196,15 +196,16 @@ public class ScalePanel extends JPanel implements MouseMotionListener, MouseList
 \r
         SequenceGroup sg = av.getSelectionGroup();\r
 \r
-        if (res > sg.getStartRes())\r
-        {\r
+        if(sg!=null){\r
+          if (res > sg.getStartRes())\r
+          {\r
             sg.setEndRes(res);\r
-        }\r
-        else if (res < sg.getStartRes())\r
-        {\r
+          }\r
+          else if (res < sg.getStartRes())\r
+          {\r
             sg.setStartRes(res);\r
+          }\r
         }\r
-\r
         stretchingGroup = false;\r
         ap.repaint();\r
     }\r