特定格式的JavaFX DatePicker getValue

Question

我目前正在使用 Scene Builder 制作 javafx 场景。我想以特定格式从日期选择器中获取值。只需使用 datePicker.getValue() 即可以 yyyy-mm-dd 形式返回日期值。我想要 MMM dd, yyyy 形式。有人可以帮我吗？

目前完整的datePickerController代码是这样的

package date.picker;

import java.net.URL;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Alert;
import javafx.scene.control.Alert.AlertType;
import javafx.scene.control.Button;
import javafx.scene.control.DatePicker;
import javafx.scene.control.TextField;
import javafx.util.StringConverter;

/**
 * FXML Controller class
 *
 * @author Dushyant Patel
 */
public class DatePickerController implements Initializable {

@FXML
private TextField display;
@FXML
private DatePicker datePicker;
@FXML
private Button getDateBtn;
@FXML
private Button setDateBtn;

@FXML
private void getDateAction(ActionEvent event) {

    LocalDate date = datePicker.getValue();
    if (date != null) {
        display.setText(date.toString());
    } else {
        display.setText("");
    }
}

@FXML
private void datePickerAction(ActionEvent event) {
    LocalDate date = datePicker.getValue();
    if (date != null) {
        display.setText(date.toString());
    } else {
        display.setText("");
    }
}

@FXML
private void setDateAction(ActionEvent event) {
    if (!display.getText().trim().equals("")) {
        if (display.getText().length() != 10) {
            Alert alert = new Alert(AlertType.ERROR);
            alert.setTitle("Error Dialog");
            alert.setHeaderText("Date Error");
            alert.setContentText("Please type date in the correct date format!");

            alert.showAndWait();
        } else {
            LocalDate date = LocalDate.parse(display.getText());
            datePicker.setValue(date);
        }
    } else {
        datePicker.setValue(null);
    }

}

/**
 * Initializes the controller class.
 */
@Override
public void initialize(URL url, ResourceBundle rb) {
    String pattern = "MMM dd, yyyy";
    StringConverter converter = new StringConverter<LocalDate>() {
        DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern(pattern);

        @Override
        public String toString(LocalDate date) {
            if (date != null) {
                return dateFormatter.format(date);
            } else {
                return "";
            }
        }

        @Override
        public LocalDate fromString(String string) {
            if (string != null && !string.isEmpty()) {
                return LocalDate.parse(string, dateFormatter);
            } else {
                return null;
            }
        }
    };

    datePicker.setConverter(converter);
}

}

Answer 1

DataPicker在数据选择器中引用转换器

 datePicker.setConverter(new StringConverter<LocalDate>() {
 String pattern = "yyyy-MM-dd";
 DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern(pattern);

 {
     datePicker.setPromptText(pattern.toLowerCase());
 }

 @Override public String toString(LocalDate date) {
     if (date != null) {
         return dateFormatter.format(date);
     } else {
         return "";
     }
 }

 @Override public LocalDate fromString(String string) {
     if (string != null && !string.isEmpty()) {
         return LocalDate.parse(string, dateFormatter);
     } else {
         return null;
     }
 }
});