format - JavaFX Table Cell Formatting

Question

    TableColumn<Event,Date> releaseTime  = new TableColumn<>("Release Time");
    releaseTime.setCellValueFactory(
                new PropertyValueFactory<Event,Date>("releaseTime")
            );

How can I change the format of releaseTime? At the moment it calls a simple toString on the Date object.

Answer 1

If you want to preserve the sorting capabilities of your TableColumn, none of the solutions above is valid: if you convert your Date to a String and show it that way in your TableView; the table will sort it as such (so incorrectly).

The solution I found was subclassing the Date class in order to override the toString() method. There is a caveat here though: the TableView uses java.sql.Date instead of java.util.Date; so you need to subclass the former.

import java.text.SimpleDateFormat;

public class CustomDate extends java.sql.Date {

    public CustomDate(long date) {
        super(date);
    }

    @Override
    public String toString() {
        return new SimpleDateFormat("dd/MM/yyyy").format(this);
    }
}

The table will call that method in order to print the date.

Of course, you need to change too your Date class in the TableColumn declaration to the new subclass:

@FXML
TableColumn<MyObject, CustomDate> myDateColumn;

Same thing when you attach your object attribute to the column of your table:

myDateColumn.setCellValueFactory(new PropertyValueFactory< MyObject, CustomDate>("myDateAttr"));

And finally, for the shake of clarity this is how you declare the getter in your object class:

public CustomDate getMyDateAttr() {
    return new CustomDate(myDateAttr.getTime()); //myDateAttr is a java.util.Date           
}

It took me a while to figure out this due to the fact that it uses java.sql.Date behind the scenes; so hopefully this will save other people some time!