JavaFX ComboBox - Display text but return ID on selection

Question

I have a Database table with airports, each airport has a name and an ID.

In JavaFX I have a form, with a ComboBox, the combobox needs to display all the ai

Answer 1

Your Airport Class.. .

public class Airport {

private int id;
private String name;

public Airport(int id, String name) {
    super();
    this.id = id;
    this.name = name;
}

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

}// class Airport

Create Observable list of Airport

ObservableList<AirPort> airports = FXCollections.observableArrayList();
airports.add(new Airport(1, "Beijing Capital International Airport"));
airports.add(new Airport(2, "Los Angeles International Airport"));
airports.add(new Airport(3, "London Heathrow Airport"));

Set item of your combo box. .

combo.setItems(airports);

After this when you run your program you get the output like this. ..

To get name of Airports you have to need to override toString method in Airport class.

@Override
public String toString() {
    return this.getName();
}

After this you will get output like.. .

---

Now to get the id of selected airport you can set an event handler. .

private void setEventOnAirport() {
    combo.setOnKeyReleased(event -> {
        if (event.getCode().equals(KeyCode.ENTER)) {
            Airport airport = combo.getSelectionModel().getSelectedItem();
            System.out.println(airport.getId());
        }
    });
}

By this function you can see the ID of selected Airport. . .

Answer 2

You can create e.g. an AirPort class with ID and name members and a ComboBox that displays these objects: ComboBox<AirPort>.

AirPort class:

public class AirPort {
    private int ID;
    private String name;

    public AirPort(int id, String name) {
        this.ID = id;
        this.name = name;
    }

    public int getID() { return ID; }
    public String getName() { return name; }
}

Get the items from the DB and create the ComboBox:

// Fill the list from the DataBase
ObservableList<AirPort> airports = FXCollections.observableArrayList();
airports.addAll(new AirPort(0, "Heathrow"), 
    new AirPort(1, "Frankfurt"),
    new AirPort(2, "NewYork"));

ComboBox<AirPort> combo = new ComboBox<>();
combo.setItems(airports);

Finally to display the name of the objects you can use for example a StringConverter:

combo.setConverter(new StringConverter<AirPort>() {

    @Override
    public String toString(AirPort object) {
        return object.getName();
    }

    @Override
    public AirPort fromString(String string) {
        return combo.getItems().stream().filter(ap -> 
            ap.getName().equals(string)).findFirst().orElse(null);
    }
});

And then when the value is changing you get back AirPort objects which contains the needed ID:

combo.valueProperty().addListener((obs, oldval, newval) -> {
    if(newval != null)
        System.out.println("Selected airport: " + newval.getName() 
            + ". ID: " + newval.getID());
});