Function setOnKeyPressed is not working on DatePicker in Javafx?

问题

Function setOnKeyPressed is not working on DatePicker. I want to change the focus from first datepicker(startYear) to second datepicker(endyear) whenever Enter or Down key is pressed, but its not working. I'hv tried the following code. Please help me out...!!

package datedemo;

import com.sun.javafx.robot.FXRobot;
import com.sun.javafx.robot.FXRobotFactory;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.Calendar;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.DatePicker;
import javafx.scene.control.Label;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.Priority;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

/**
 *
 * @author vikassingh
 */
public class DateDemo extends Application {

    DatePicker startYear = new DatePicker();
    DatePicker endYear = new DatePicker();

    @Override
    public void start(Stage primaryStage) {
        /* Button btn = new Button();
         btn.setText("Say 'Hello World'");
         btn.setOnAction(new EventHandler<ActionEvent>() {

         @Override
         public void handle(ActionEvent event) {
         System.out.println("Hello World!");
         }
         }); */

        // Year Start and END 
        int start_year = 0;
        int end_year = 0;
        Calendar cal = Calendar.getInstance();
        int year = cal.get(cal.YEAR);
        int month = cal.get(cal.MONTH) + 1; //zero-based
        System.out.println("year = " + year + "\nmonth = " + month);
        if (month < 4) {
            start_year = year - 1;
            end_year = year;
        } else {
            start_year = year;
            end_year = year + 1;
        }

        String start_year_date = "01/04/" + start_year;
        String end_year_date = "31/03/" + end_year;

        //Get Start & End Date;
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
        LocalDate startDate = LocalDate.parse(start_year_date, formatter);
        LocalDate endDate = LocalDate.parse(end_year_date, formatter);

        VBox box = new VBox();
        VBox.setVgrow(box, Priority.ALWAYS);

        Label startYearLabel = new Label("Start Year * :");
        box.getChildren().add(startYearLabel);

        startYear.setValue(startDate);
        startYear.setPromptText("DD/MM/YYYY");
        box.getChildren().add(startYear);
        Label endYearLabel = new Label("End Year * :");
        box.getChildren().add(endYearLabel);
        endYear.setValue(endDate);
        endYear.setPromptText("DD/MM/YYYY");
        box.getChildren().add(endYear);

        StackPane root = new StackPane();
        root.getChildren().add(box);

        Scene scene = new Scene(root, 300, 250);

        primaryStage.setTitle("Date Demo");
        primaryStage.setScene(scene);
        primaryStage.show();

        // Listner
        startYear.setOnKeyPressed(new EventHandler<KeyEvent>() {
            public void handle(KeyEvent event) {
                if (event.getCode() == KeyCode.ENTER || event.getCode() == KeyCode.TAB || event.getCode() == KeyCode.DOWN) {
                    endYear.requestFocus();
                    event.consume();
                }
                if (event.getCode() == KeyCode.UP) {
                    // do something
                    event.consume();
                }
            }
        });

        endYear.setOnKeyPressed(new EventHandler<KeyEvent>() {
            public void handle(KeyEvent event) {
                if (event.getCode() == KeyCode.ENTER || event.getCode() == KeyCode.TAB || event.getCode() == KeyCode.DOWN) {
                   // do something
                    event.consume();
                }
                if (event.getCode() == KeyCode.UP) {
                    startYear.requestFocus();
                    event.consume();
                }
            }
        });
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        launch(args);
    }

}

回答1:

Use an EventFilter, i. e.

startYear.addEventFilter(KeyEvent.KEY_PRESSED, event -> {
...
});

endYear.addEventFilter(KeyEvent.KEY_PRESSED, event -> {
...
});

i. e.

startYear.addEventFilter(KeyEvent.KEY_PRESSED, event -> {

        if (event.getCode() == KeyCode.ENTER || event.getCode() == KeyCode.TAB || event.getCode() == KeyCode.DOWN) {
            endYear.requestFocus();
            event.consume();
        }
        if (event.getCode() == KeyCode.UP) {
            // do something
            event.consume();
        }
});

endYear.addEventFilter(KeyEvent.KEY_PRESSED, event -> {
        if (event.getCode() == KeyCode.ENTER || event.getCode() == KeyCode.TAB || event.getCode() == KeyCode.DOWN) {
           // do something
            event.consume();
        }
        if (event.getCode() == KeyCode.UP) {
            startYear.requestFocus();
            event.consume();
        }
});

来源：https://stackoverflow.com/questions/34690099/function-setonkeypressed-is-not-working-on-datepicker-in-javafx