JavaFx UI控件2 - JavaFX DatePicker - 《JavaSE 阶段》

DatePicker创建
自定义日期选择器
DateCell
示例

JavaFX DatePicker允许从给定日历中选择一天。DatePicker控件包含一个带有日期字段和日期选择器的组合框。JavaFX DatePicker控件使用JDK8日期时间API。

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.DatePicker;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class Main extends Application {
    public static void main(String[] args) {
        launch(args);
    }
    @Override
    public void start(Stage stage) {
        VBox vbox = new VBox(20);
        Scene scene = new Scene(vbox, 400, 400);
        stage.setScene(scene);
        DatePicker checkInDatePicker = new DatePicker();
        vbox.getChildren().add(checkInDatePicker);
        stage.show();
    }
}

DatePicker创建

我们可以创建一个DatePicker并在类构造函数中设置一个特定的日期值。

dateP = new DatePicker(LocalDate.of(2018, 10, 8));

还可以使用setValue()方法设置日期值。

checkInDatePicker.setValue(LocalDate.of(2014, 10, 8));
checkInDatePicker.setValue(LocalDate.now());

以下代码使用setValue()向结束DatePicker添加更多时间。

import java.time.LocalDate;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.DatePicker;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class Main extends Application {
    public static void main(String[] args) {
        launch(args);
    }
    @Override
    public void start(Stage stage) {
        VBox vbox = new VBox(20);
        Scene scene = new Scene(vbox, 400, 400);
        stage.setScene(scene);
        DatePicker startDatePicker = new DatePicker();
        DatePicker endDatePicker = new DatePicker();
        startDatePicker.setValue(LocalDate.now());
        endDatePicker.setValue(startDatePicker.getValue().plusDays(1));
        vbox.getChildren().add(new Label("Start Date:"));
        vbox.getChildren().add(startDatePicker);
        vbox.getChildren().add(new Label("End Date:"));
        vbox.getChildren().add(endDatePicker);
        stage.show();
    }
}

自定义日期选择器

可以通过使用setShowWeekNumbers()方法来启用和禁用在DatePicker中显示ISO周数。

dateP.setShowWeekNumbers(true);

默认情况下，DatePicker使用系统区域设置和ISO日历系统定义的日期格式

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.DatePicker;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.StringConverter;
public class Main extends Application {
    public static void main(String[] args) {
        launch(args);
    }
    @Override
    public void start(Stage stage) {
        String pattern = "yyyy-MM-dd";
        VBox vbox = new VBox(20);
        Scene scene = new Scene(vbox, 400, 400);
        stage.setScene(scene);
        DatePicker checkInDatePicker = new DatePicker();
        StringConverter<LocalDate> 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;
                }
            }
        };
        checkInDatePicker.setConverter(converter);
        checkInDatePicker.setPromptText(pattern.toLowerCase());
        vbox.getChildren().add(checkInDatePicker);
        checkInDatePicker.requestFocus();
        stage.show();
    }
}

DateCell

默认情况下，日历元素中的所有单元格都可供选择。可以使用日期单元工厂禁用单元格。

import java.time.LocalDate;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.DateCell;
import javafx.scene.control.DatePicker;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.Callback;
public class Main extends Application {
    public static void main(String[] args) {
        launch(args);
    }
    @Override
    public void start(Stage stage) {
        VBox vbox = new VBox(20);
        Scene scene = new Scene(vbox, 400, 400);
        stage.setScene(scene);
        DatePicker startDatePicker = new DatePicker();
        DatePicker endDatePicker = new DatePicker();
        startDatePicker.setValue(LocalDate.now());
        final Callback<DatePicker, DateCell> dayCellFactory = new Callback<DatePicker, DateCell>() {
            @Override
            public DateCell call(final DatePicker datePicker) {
                return new DateCell() {
                    @Override
                    public void updateItem(LocalDate item, boolean empty) {
                        super.updateItem(item, empty);
                        if (item.isBefore(startDatePicker.getValue().plusDays(1))) {
                            setDisable(true);
                            setStyle("-fx-background-color: #EEEEEE;");
                        }
                    }
                };
            }
        };
        endDatePicker.setDayCellFactory(dayCellFactory);
        endDatePicker.setValue(startDatePicker.getValue().plusDays(1));
        vbox.getChildren().add(new Label("Start Date:"));
        vbox.getChildren().add(startDatePicker);
        vbox.getChildren().add(new Label("End Date:"));
        vbox.getChildren().add(endDatePicker);
        stage.show();
    }
}

示例

为每个日期单元格安装工具提示。

import java.time.LocalDate;
import java.time.temporal.ChronoUnit;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.DateCell;
import javafx.scene.control.DatePicker;
import javafx.scene.control.Label;
import javafx.scene.control.Tooltip;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.Callback;
public class Main extends Application {
    public static void main(String[] args) {
        launch(args);
    }
    @Override
    public void start(Stage stage) {
        VBox vbox = new VBox(20);
        Scene scene = new Scene(vbox, 400, 400);
        stage.setScene(scene);
        final DatePicker startDatePicker = new DatePicker();
        DatePicker endDatePicker = new DatePicker();
        startDatePicker.setValue(LocalDate.now());
        final Callback<DatePicker, DateCell> dayCellFactory = new Callback<DatePicker, DateCell>() {
            @Override
            public DateCell call(final DatePicker datePicker) {
                return new DateCell() {
                    @Override
                    public void updateItem(LocalDate item, boolean empty) {
                        super.updateItem(item, empty);
                        long p = ChronoUnit.DAYS.between(startDatePicker.getValue(), item);
                        setTooltip(new Tooltip("You're about to stay for " + p + " days"));
                    }
                };
            }
        };
        endDatePicker.setDayCellFactory(dayCellFactory);
        endDatePicker.setValue(startDatePicker.getValue().plusDays(1));
        vbox.getChildren().add(new Label("Start Date:"));
        vbox.getChildren().add(startDatePicker);
        vbox.getChildren().add(new Label("End Date:"));
        vbox.getChildren().add(endDatePicker);
        stage.show();
    }
}