复选框和组合框 javaFX [关闭]

Question

我想知道，哪些复选框被选中，哪些未被选中。 此外，我想了解如何在 ChomboBox、E.G. 中添加标签。有数字可供选择，1-9有标题“弱”，10-20有标题“强”，但只能从数字中选择，不能从标题中选择。

感谢您的建议

import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.fxml.Initializable;
import javafx.scene.control.*;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.text.Font;

import java.net.URL;
import java.util.ResourceBundle;

public class Controller implements Initializable {
    public Label l1,l2,l3,l4,l5,l6,l7,l8;
    public Button generovatB;
    public TextField jtxt1;
    public ComboBox cbox1;
    public CheckBox cb1,cb2,cb3,cb4,cb7;
    public Font x2;
    public ImageView imgvBck;
    //created by Z.K. =
    private char[] lower = {'a','b','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};
    private char[] upper = {'A','B','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
    private char[] special = {'#','&','@','{','}','[',']','+','-','*','/','?','.',':','!','§',')','(','/','%','=',';','<','>','ß','$'};
    private char[] numbers = {'1','2','3','4','5','6','7','8','9','0'};
    private String[] words = new String[1000];



    public void generovatB(ActionEvent actionEvent) {


    }


    public void naplnPole(){


}

    @Override
    public void initialize(URL location, ResourceBundle resources) {
        Image pozadi = new Image("obr.png",650,500,true,false,false);
        imgvBck.setImage(pozadi);
        ObservableList<String> options =
                FXCollections.observableArrayList("5","7","9","15","18"
                );
        cbox1.setItems(options);

    }
}

Answer 1

我会使用 ListCell 来修改 ComboBox 中的文本：

cbox1.getSelectionModel().selectedItemProperty().addListener((ObservableValue< ? extends String> observable, String oldValue, String newValue) -> {
        ListCell<String> lc = new ListCell<>();
        if (Integer.valueOf(newValue) < 10) {
            lc.setText("Weak (" + newValue + ")");
        } else if (Integer.valueOf(newValue) < 21) {
            lc.setText("Strong (" + newValue + ")");
        } else {
            lc.setText("");
        }
        cbox1.setButtonCell(lc);
    });

对于您的其他问题，有多个选项可用于获取选中和未选中复选框的方法。最简单的方法是将您的 CheckBoxes 添加到 Array 和循环中。根据具体需求，还有许多其他方法可以实现这一目标。如果您添加更多详细信息，我可能会尽力提供帮助。

Answer 2

我可能不确定，但如果我正确理解您的问题，您希望将组合框中的数字与标题分组，并让用户使用复选框来选择它们。您还可以找到选择了哪些数字。

如果这是您的问题，正如@Daniel 建议的那样，您必须使用 ListCell 来修改单元格中的内容。首先，我建议为组合框设置一个单独的模型来处理选择。这比检查所选项目的所有 CheckBox 更容易处理。

class Level {
        private IntegerProperty level = new SimpleIntegerProperty();
        private BooleanProperty selected = new SimpleBooleanProperty();
        ...
}

为了实现 CheckBox，您可以使用 CheckBoxListCell，但由于您需要额外的要求来显示组标题，所以这可能不正确。所以我建议根据需求创建自定义单元工厂。

// Implementing with CheckBoxListCell
Callback<ListView<Level>, ListCell<Level>> forListView = CheckBoxListCell.forListView(Level::selectedProperty);
comboBox.setCellFactory(forListView);

您需要考虑的另一个步骤是关闭单击任何单元格时弹出的自动隐藏功能。这将允许您在不关闭弹出窗口的情况下进行多项选择。

final ComboBox<Level> comboBox = new ComboBox<Level>(items) {
            protected javafx.scene.control.Skin<?> createDefaultSkin() {
                return new ComboBoxListViewSkin<Level>(this) {
                    @Override
                    protected boolean isHideOnClickEnabled() {
                        return false;
                    }
                };
            }
        };

要查找选定的数字，您只需遍历 ComboBox 中的项目并检查模型的选定值。

comboBox.getItems().stream().filter(Level::isSelected).forEach(selectedItem->{
      // Do with your selected item
});

考虑到以上所有，根据我对问题的理解，下面是一个工作演示。

import com.sun.javafx.scene.control.skin.ComboBoxListViewSkin;
import javafx.application.Application;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.VBox;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javafx.util.Callback;

import java.util.stream.Collectors;

public class HeadingInComboBoxDemo extends Application {

    private final int WEAK_INDEX = -1;
    private final int STRONG_INDEX = -2;

    @Override
    public void start(Stage stage) throws Exception {
        VBox root = new VBox();
        root.setSpacing(15);
        root.setPadding(new Insets(25));
        root.setAlignment(Pos.TOP_LEFT);
        Scene sc = new Scene(root, 600, 600);
        stage.setScene(sc);
        stage.show();

        final ObservableList<Level> items = FXCollections.observableArrayList();
        for (int i = 1; i < 11; i++) {
            if (i == 1) {
                items.add(new Level(WEAK_INDEX));
            } else if (i == 6) {
                items.add(new Level(STRONG_INDEX));
            }
            items.add(new Level(i));
        }

        final ComboBox<Level> comboBox = new ComboBox<Level>(items) {
            protected javafx.scene.control.Skin<?> createDefaultSkin() {
                return new ComboBoxListViewSkin<Level>(this) {
                    @Override
                    protected boolean isHideOnClickEnabled() {
                        return false;
                    }
                };
            }
        };
        comboBox.setPrefWidth(150);
        comboBox.setItems(items);
        comboBox.setCellFactory(new Callback<ListView<Level>, ListCell<Level>>() {
            @Override
            public ListCell<Level> call(ListView<Level> param) {
                return new ListCell<Level>() {
                    private CheckBox cb = new CheckBox();
                    private BooleanProperty booleanProperty;

                    {
                        cb.setOnAction(e->getListView().getSelectionModel().select(getItem()));
                    }
                    @Override
                    protected void updateItem(Level item, boolean empty) {
                        super.updateItem(item, empty);
                        if (!empty) {
                            if (item.getLevel() == WEAK_INDEX || item.getLevel() == STRONG_INDEX) {
                                Label lbl = new Label(item.getLevel() == WEAK_INDEX ? "Weak" : "Strong");
                                lbl.setStyle("-fx-font-size:14px;-fx-font-weight:bold;");
                                setGraphic(lbl);
                                setText(null);
                            } else {
                                if (booleanProperty != null) {
                                    cb.selectedProperty().unbindBidirectional(booleanProperty);
                                }
                                booleanProperty = item.selectedProperty();
                                cb.selectedProperty().bindBidirectional(booleanProperty);
                                setGraphic(cb);
                                setText(item.getLevel() + "");
                            }
                        } else {
                            setGraphic(null);
                            setText(null);
                        }
                    }
                };
            }
        });

        comboBox.setButtonCell(new ListCell<Level>() {
            @Override
            protected void updateItem(Level item, boolean empty) {
                super.updateItem(item, empty);
                String selected = comboBox.getItems().stream().filter(i -> i.isSelected())
                        .map(i -> i.getLevel()).sorted()
                        .map(i -> i + "").collect(Collectors.joining(","));
                setText(selected);
            }
        });

        Text txt = new Text();
        Button show = new Button("Show Selected");
        show.setOnAction(e->{
            StringBuilder sb = new StringBuilder();
            comboBox.getItems().stream().filter(Level::isSelected).forEach(item->{
                sb.append(item.getLevel()).append("\n");
            });
            txt.setText(sb.toString());
        });

        root.getChildren().addAll(comboBox,show,txt);
    }

    public static void main(String[] args) {
        Application.launch(args);
    }

    class Level {
        private IntegerProperty level = new SimpleIntegerProperty();
        private BooleanProperty selected = new SimpleBooleanProperty();

        public Level(int level) {
            setLevel(level);
        }

        public int getLevel() {
            return level.get();
        }

        public IntegerProperty levelProperty() {
            return level;
        }

        public void setLevel(int level) {
            this.level.set(level);
        }

        public boolean isSelected() {
            return selected.get();
        }

        public BooleanProperty selectedProperty() {
            return selected;
        }

        public void setSelected(boolean selected) {
            this.selected.set(selected);
        }
    }
}