表菜单按钮不显示保存为标签、JavaFx 的列的名称

Question

我按照here 的建议将我的列名转换为标签，以便我可以得到关于它们名称的工具提示：

        for (Entry<String, String> ent : dc.getSortedAssignedOrg().entrySet()) {

        TreeTableColumn<String, ArrayList<String>> col = new TreeTableColumn<>();
        Label label = new Label(ent.getValue());
        col.setGraphic(label);
        col.setEditable(false);
        col.setSortable(false);
        label.setTooltip(new Tooltip(label.getText()));// tooltip for column
            .
            .
            .

现在的问题是我的 TableMenuButton 没有显示列名，单击 treetableview 右上角的加号会打开一个列表，其中只有选中的符号，我可以删除或添加它。但名称本身并未显示。我该如何解决这个问题？

Answer 1

您可以创建自己的表格菜单。无论如何，您最好使用自定义菜单，因为内置菜单 e。 G。每次单击按钮时关闭。不幸的是，上下文菜单没有 getter，因此您必须通过反射或查找来访问它。

我通过reflection 和lookup 机制为自定义菜单创建了一个要点。也许对你有帮助。

对你来说相关的部分是

CheckBox cb = new CheckBox(tableColumn.getText());

您将菜单项设置为您偏好的文本，即。 e.标签的文本。

---

这是 TreeTableView 的查找版本：

CustomTreeTableMenuDemo.java

import java.util.Arrays;
import java.util.List;

import javafx.application.Application;
import javafx.beans.property.ReadOnlyStringWrapper;
import javafx.beans.property.SimpleStringProperty;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeTableColumn;
import javafx.scene.control.TreeTableView;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

public class CustomTreeTableMenuDemo extends Application {

    List<Employee> employees = Arrays.<Employee> asList(new Employee(
            "Ethan Williams", "ethan.williams@example.com"), new Employee(
            "Emma Jones", "emma.jones@example.com"), new Employee(
            "Michael Brown", "michael.brown@example.com"), new Employee(
            "Anna Black", "anna.black@example.com"), new Employee(
            "Rodger York", "roger.york@example.com"), new Employee(
            "Susan Collins", "susan.collins@example.com"));

    final TreeItem<Employee> root = new TreeItem<>(new Employee(
            "Sales Department", ""));

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

    @Override
    public void start(Stage stage) {

        stage.setTitle("Table Menu Demo");
        stage.setWidth(500);
        stage.setHeight(550);

        root.setExpanded(true);
        employees.stream().forEach((employee) -> {
            root.getChildren().add(new TreeItem<>(employee));
        });
        stage.setTitle("Tree Table View Sample");
        final Scene scene = new Scene(new Group(), 400, 400);
        scene.setFill(Color.LIGHTGRAY);
        Group sceneRoot = (Group) scene.getRoot();

        TreeTableColumn<Employee, String> empColumn = new TreeTableColumn<>(
                "Employee");
        empColumn.setPrefWidth(150);
        empColumn
                .setCellValueFactory((
                        TreeTableColumn.CellDataFeatures<Employee, String> param) -> new ReadOnlyStringWrapper(
                        param.getValue().getValue().getName()));

        TreeTableColumn<Employee, String> emailColumn = new TreeTableColumn<>(
                "Email");
        emailColumn.setPrefWidth(190);
        emailColumn
                .setCellValueFactory((
                        TreeTableColumn.CellDataFeatures<Employee, String> param) -> new ReadOnlyStringWrapper(
                        param.getValue().getValue().getEmail()));

        TreeTableView<Employee> treeTableView = new TreeTableView<>(root);
        treeTableView.getColumns().setAll(empColumn, emailColumn);

        sceneRoot.getChildren().add(treeTableView);

        stage.setScene(scene);
        stage.show();

        // enable table menu button and add a custom menu to it
        TreeTableUtils.addCustomTreeTableMenu(treeTableView);
    }

    public class Employee {

        private SimpleStringProperty name;
        private SimpleStringProperty email;

        public SimpleStringProperty nameProperty() {
            if (name == null) {
                name = new SimpleStringProperty(this, "name");
            }
            return name;
        }

        public SimpleStringProperty emailProperty() {
            if (email == null) {
                email = new SimpleStringProperty(this, "email");
            }
            return email;
        }

        private Employee(String name, String email) {
            this.name = new SimpleStringProperty(name);
            this.email = new SimpleStringProperty(email);
        }

        public String getName() {
            return name.get();
        }

        public void setName(String fName) {
            name.set(fName);
        }

        public String getEmail() {
            return email.get();
        }

        public void setEmail(String fName) {
            email.set(fName);
        }
    }
}

TreeTableUtils.java

import javafx.collections.ObservableList;
import javafx.event.EventHandler;
import javafx.geometry.Side;
import javafx.scene.Node;
import javafx.scene.control.CheckBox;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.CustomMenuItem;
import javafx.scene.control.Label;
import javafx.scene.control.SeparatorMenuItem;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TreeTableColumn;
import javafx.scene.control.TreeTableView;
import javafx.scene.input.MouseEvent;

import com.sun.javafx.scene.control.skin.TableHeaderRow;
import com.sun.javafx.scene.control.skin.TreeTableViewSkin;

public class TreeTableUtils {

    /**
     * Make table menu button visible and replace the context menu with a custom context menu via reflection.
     * The preferred height is modified so that an empty header row remains visible. This is needed in case you remove all columns, so that the menu button won't disappear with the row header.
     * IMPORTANT: Modification is only possible AFTER the table has been made visible, otherwise you'd get a NullPointerException
     * @param treeTableView
     */
    public static void addCustomTreeTableMenu( TreeTableView treeTableView) {

        // enable table menu
        treeTableView.setTableMenuButtonVisible(true);

        // replace internal mouse listener with custom listener 
        setCustomContextMenu( treeTableView);

    }

    private static void setCustomContextMenu( TreeTableView treeTableView) {

        TreeTableViewSkin<?> treeTableViewSkin = (TreeTableViewSkin<?>) treeTableView.getSkin();

        // get all children of the skin
        ObservableList<Node> children = treeTableViewSkin.getChildren();

        // find the TableHeaderRow child
        for (int i = 0; i < children.size(); i++) {

            Node node = children.get(i);

            if (node instanceof TableHeaderRow) {

                TableHeaderRow tableHeaderRow = (TableHeaderRow) node;

                // setting the preferred height for the table header row
                // if the preferred height isn't set, then the table header would disappear if there are no visible columns
                // and with it the table menu button
                // by setting the preferred height the header will always be visible
                // note: this may need adjustments in case you have different heights in columns (eg when you use grouping)
                double defaultHeight = tableHeaderRow.getHeight();
                tableHeaderRow.setPrefHeight(defaultHeight);

                for( Node child: tableHeaderRow.getChildren()) {

                    // child identified as cornerRegion in TableHeaderRow.java
                    if( child.getStyleClass().contains( "show-hide-columns-button")) {

                        // get the context menu
                        ContextMenu columnPopupMenu = createContextMenu( treeTableView);

                        // replace mouse listener
                        child.setOnMousePressed(me -> {
                            // show a popupMenu which lists all columns
                            columnPopupMenu.show(child, Side.BOTTOM, 0, 0);
                            me.consume();
                        });
                    }
                }

            }
        }
    }

    /**
     * Create a menu with custom items. The important thing is that the menu remains open while you click on the menu items.
     * @param cm
     * @param treeTableView
     */
    private static ContextMenu createContextMenu( TreeTableView treeTableView) {

        ContextMenu cm = new ContextMenu();

        // create new context menu
        CustomMenuItem cmi;

        // select all item
        Label showAll = new Label("Show all");
        showAll.addEventHandler(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {

            @Override
            public void handle(MouseEvent event) {
                for (Object obj : treeTableView.getColumns()) {
                    ((TableColumn<?, ?>) obj).setVisible(true);
                }
            }

        });

        cmi = new CustomMenuItem(showAll);
        cmi.setHideOnClick(false);
        cm.getItems().add(cmi);

        // deselect all item
        Label hideAll = new Label("Hide all");
        hideAll.addEventHandler(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {

            @Override
            public void handle(MouseEvent event) {

                for (Object obj : treeTableView.getColumns()) {
                    ((TableColumn<?, ?>) obj).setVisible(false);
                }
            }

        });

        cmi = new CustomMenuItem(hideAll);
        cmi.setHideOnClick(false);
        cm.getItems().add(cmi);

        // separator
        cm.getItems().add(new SeparatorMenuItem());

        // menu item for each of the available columns
        for (Object obj : treeTableView.getColumns()) {

            TreeTableColumn<?, ?> tableColumn = (TreeTableColumn<?, ?>) obj;

            CheckBox cb = new CheckBox(tableColumn.getText());
            cb.selectedProperty().bindBidirectional(tableColumn.visibleProperty());

            cmi = new CustomMenuItem(cb);
            cmi.setHideOnClick(false);

            cm.getItems().add(cmi);
        }

        return cm;
    }
}