Is there a way to use the GregorianCalendar on the JavaFX TableView?

Question

Is there a way to have a column in the TableView show a proper date instead of:

java.util.GregorianCalendar[time=?areFieldsSet=false...

I want to know because it's irritating having it displayed like that on the Date column I have and having to switch between Date and GregorianCalendar get's messy and annoying.

Answer 1

First, I would strongly recommend using the java.time API, instead of legacy classes such as java.util.Calendar and java.util.Date, etc.

In any case, you can change how data in cells in a given column are displayed by using a cell factory on the column. In the case where your cell value factory is generating Calendar instances, you presumably have

TableColumn<MyTableType, Calendar> dateColumn ;
// ...
dateColumn.setCellValueFactory(...);

You can additionally do

DateFormat dateFormat = DateFormat.getDateInstance();
dateColumn.setCellFactory(col -> new TableCell<MyTableType, Calendar>() {
    @Override
    protected void updateItem(Calendar date, boolean empty) {
        super.updateItem(date, empty);
        if (empty) {
            setText(null);
        } else {
            setText(dateFormat.format(date.getTime()));
        }
    }
});

If you use the aforementioned java.time API, you represent a date with LocalDate and use a DateTimeFormatter to do the formatting:

TableColumn<MyTableType, LocalDate> dateColumn ;
// ...
dateColumn.setCellValueFactory(...);
DateTimeFormatter dateFormat = DateTimeFormatter.ISO_LOCAL_DATE;
dateColumn.setCellFactory(col -> new TableCell<MyTableType, LocalDate>() {
    @Override
    protected void updateItem(LocalDate date, boolean empty) {
        super.updateItem(date, empty);
        if (empty) {
            setText(null);
        } else {
            setText(dateFormat.format(date));
        }
    }
});