Merge pull request #6531 from JabRef/fixEntryTypeMissing

Allow entrytype as sorting criterion

CHANGELOG.md

@@ -24,6 +24,7 @@ Note that this project **does not** adhere to [Semantic Versioning](http://semve
 - We fixed the bug when strike the delete key in the text field. [#6421](https://github.com/JabRef/jabref/issues/6421)
 - We added a BibTex key modifier for truncating strings. [#3915](https://github.com/JabRef/jabref/issues/3915)
 - We added support for jumping to target entry when typing letter/digit after sorting a column in maintable [#6146](https://github.com/JabRef/jabref/issues/6146)
+- We added the field "entrytype" to the export sort criteria [#6531](https://github.com/JabRef/jabref/pull/6531)
 
 ### Changed
 

src/main/java/org/jabref/gui/libraryproperties/LibraryPropertiesDialogViewModel.java

@@ -26,6 +26,7 @@
 import org.jabref.model.database.shared.DatabaseLocation;
 import org.jabref.model.entry.field.Field;
 import org.jabref.model.entry.field.FieldFactory;
+import org.jabref.model.entry.field.InternalField;
 import org.jabref.model.metadata.MetaData;
 import org.jabref.model.metadata.SaveOrderConfig;
 import org.jabref.preferences.PreferencesService;
@@ -106,6 +107,8 @@ void setValues() {
         }
 
         Set<Field> fieldNames = FieldFactory.getCommonFields();
+        // allow entrytype field as sort criterion
+        fieldNames.add(InternalField.TYPE_HEADER);
         primarySortFieldsProperty.addAll(fieldNames);
         secondarySortFieldsProperty.addAll(fieldNames);
         tertiarySortFieldsProperty.addAll(fieldNames);