Add a check for undefined value

Author: andreh11

CHANGELOG.md

@@ -5,6 +5,7 @@ All notable changes to this project will be documented in this file.
 ## Unreleased
 
 ### Added
+  - *Field map* − Add button, menu and shortcuts to expand/collapse location level. 
   - Keyboard shortcuts for the most common actions (see user guide in the wiki
    for more details).
   - *Settings* − Add restart snackbar.
@@ -19,7 +20,6 @@ All notable changes to this project will be documented in this file.
     version. Each script will applied successively to reach the latest version.
 
 ### Changed
-  - *Field map* − Add shortcut to show/hide the plantings pane.
   - *Field map* − Attach show/hide button to the plantings pane.
   - Update French translation.
 

desktop/qml/LocationsPage.qml

@@ -311,6 +311,8 @@ Page {
                             text: index + 1
                             checkable: true
                             checked: expandButton.expandBoolList[index]
+                                     ? expandButton.expandBoolList[index]
+                                     : false
                             onTriggered: expandButton.expandLevel(index)
                         }
                     }