在 javafx 中单击组合框时如何刷新数据？

Question

每次我按下时，Combobox我都想从每个不同的值中刷新数据database

但是我每次按下组合框时得到的是，数据会继续增加而不是刷新

截图

public void initialize(URL url, ResourceBundle rb) {

        con = new DBConnect();

        con.connect();

        depart();

    }   

void init(Stage stage) {

        this.stage = stage;

    }

    public void depart(){

        String sql = "SELECT DISTINCT b.nama_bandara FROM departure as depart "

                + "INNER JOIN bandara as b on b.kode_bandara = depart.kode_bandara";

        try {

            pst = con.conn.prepareStatement(sql);

            con.rs = pst.executeQuery();

            while(con.rs.next()){

                combo.getItems().addAll(con.rs.getString(1));

            }

        } catch (SQLException ex) {

            Logger.getLogger(FXMLDocumentController.class.getName()).log(Level.SEVERE, null, ex);

        }

    }

每次我点击，数据总是增加

@FXML

    private void CB(ActionEvent event) {

        String depart = combo.getValue();

        String sql = "SELECT b.kota, bb.kota, single.harga FROM single_trip as single \n" +

                    "INNER JOIN departure as depart ON depart.kode_departure = single.kode_departure \n" +

                    "INNER JOIN bandara as b on b.kode_bandara = depart.kode_bandara \n" +

                    "INNER JOIN arrived as arrive on arrive.kode_arrived = single.kode_arrived \n" +

                    "INNER JOIN bandara as bb on bb.kode_bandara = arrive.kode_bandara \n" +

                    "WHERE b.nama_bandara = '"+depart+"'";

Answer 1

您正在使用 addAll - 添加到列表中。尝试改用setAll