--- a/FileApplicationNoteBook.st	Sun Sep 08 16:29:11 2019 +0200
+++ b/FileApplicationNoteBook.st	Sun Sep 08 16:33:59 2019 +0200
@@ -2113,7 +2113,7 @@
 
     self canViewFile ifFalse:[^ self].
     master := self masterApplication.
-    self selection size = 1 ifFalse:[
+    self selection size == 1 ifFalse:[
         Dialog warn:'only one file has to be selected'.
         ^ self.
     ].
@@ -2833,10 +2833,7 @@
 !
 
 hasOneSelectionInList
-
-    | sel |
-    sel := self selection.
-    ^ (sel notNil and:[sel notEmpty and:[sel size = 1]])
+    ^ self selection size == 1
 
     "Modified: / 21-06-2018 / 15:05:50 / Claus Gittinger"
 !