CommitEdit-Funktion wird beim Erstellen der Tabelle ausgeführt

Question

Ich habe eine benutzerdefinierte bearbeitbare Tabellenzelle für meine Tabellenansicht. Nun, das Problem, das ich habe, ist, dass die commitEdit() Funktion ausgeführt wird, wenn die Tabelle erstellt wird. Das Problem ist, dass es das Programm verlangsamt, während ich Elemente in meiner Datenbank aktualisiere und jedes einzelne Element aktualisiert wird.

public class ChoiceBoxCell extends TableCell<Student, Classroom> { 

    ChoiceBox<Classroom> classroomChoiceBox; 

    public ChoiceBoxCell(ObservableList<Classroom> classroomObservableList) { 
     classroomChoiceBox = new ChoiceBox<>(); 
     classroomChoiceBox.setItems(classroomObservableList); 

     classroomChoiceBox.getSelectionModel().selectedItemProperty().addListener((obs, oldValue, newValue) -> { 
      if (newValue != null) { 
       processEdit(newValue); 
      } 
     }); 
    } 
    private void processEdit(Classroom value) { 
     commitEdit(value); 
     classroomChoiceBox.setValue(value); 
     setGraphic(classroomChoiceBox); 
    } 

    @Override 
    public void cancelEdit() { 
     super.cancelEdit(); 
     setGraphic(classroomChoiceBox); 
    } 

    @Override 
    public void commitEdit(Classroom value) { // gets executed on start up 
     super.commitEdit(value); 
     Student student = (Student) getTableRow().getItem(); 
     student.setClassroom(value); 
     new StudentDao().updateStudent(student); // students get updated for no reason 
     classroomChoiceBox.setValue(value); 
     setGraphic(classroomChoiceBox); 
    } 

    @Override 
    public void startEdit() { 
     super.startEdit(); 
     Classroom value = getItem(); 
     if (value != null) { 
      classroomChoiceBox.setValue(value); 
      setGraphic(classroomChoiceBox); 
     } 
    } 

    @Override 
    protected void updateItem(Classroom item, boolean empty) { 
     super.updateItem(item, empty); 
     if (item == null || empty) { 
      setGraphic(null); 
     } else { 
      classroomChoiceBox.setValue(item); 
      setGraphic(classroomChoiceBox); 
     } 
    } 
} 

EDIT: Lösung - dank

classroomChoiceBox.getSelectionModel().selectedItemProperty().addListener((obs, oldValue, newValue) -> { 
     if (newValue != null && newValue != getItem()) { 
      processEdit(newValue); 
     } 
    }); 

Answer 1

Lösung @James_D - dank James_D

classroomChoiceBox.getSelectionModel().selectedItemProperty().addListener((obs, oldValue, newValue) -> { 
     if (newValue != null && newValue != getItem()) { 
      processEdit(newValue); 
     } 
    });