edit

XLAB2/MainWindowViewModel.cs

@@ -206,6 +206,11 @@ namespace XLAB2
             }
         }
 
+        public bool IsDocumentLinesReadOnly
+        {
+            get { return !CanModifySelectedDocument(); }
+        }
+
         public DateTime? HeaderIssuedOn
         {
             get { return _headerIssuedOn; }
@@ -228,6 +233,7 @@ namespace XLAB2
                     RaiseCommandStates();
                     OnPropertyChanged("IsCustomerEditable");
                     OnPropertyChanged("IsDocumentHeaderEditable");
+                    OnPropertyChanged("IsDocumentLinesReadOnly");
                 }
             }
         }
@@ -293,6 +299,7 @@ namespace XLAB2
                     RaiseCommandStates();
                     OnPropertyChanged("IsCustomerEditable");
                     OnPropertyChanged("IsDocumentHeaderEditable");
+                    OnPropertyChanged("IsDocumentLinesReadOnly");
                     LoadSelectedDocumentAsync();
                 }
             }
@@ -2537,7 +2544,8 @@ namespace XLAB2
                 var wasDraft = selectedDocument.IsDraft;
                 var closingNow = !selectedDocument.IssuedOn.HasValue && request.IssuedOn.HasValue;
                 var printDocument = closingNow ? CreateSavedDocumentSummaryForPrint(selectedDocument, request) : null;
-                var result = await Task.Run(delegate { return _service.SaveDocument(currentDocumentNumber, request, pendingLines); });
+                var documentLinesSnapshot = DocumentLines.ToList();
+                var result = await Task.Run(delegate { return _service.SaveDocument(currentDocumentNumber, request, documentLinesSnapshot); });
 
                 _pendingLinesByDocumentKey.Remove(documentKey);
                 if (wasDraft)