javafx - Adapt TableView menu button

Question

Problem

The setTableMenuButtonVisible of a TableView provides a mechanism to change the visibility of a table column. However that functionality leaves a lot to be desired:

• The menu should remain open. I have e. g. 15 table columns and it's a pain to click menu open -> click column -> click menu open -> click next column -> ... It's a pain to change the visibility of multiple columns

• There should be a select all / deselect all functionality

• There should be a way to extend the menu with custom items

• After you deselected all columns there's no way to reselect a column because the header is gone and with it the table menu

In other words: The current implementation of the table menu is rather useless.

Question

Does anyone know of a way about how to replace the existing tableview menu with a proper one? I've seen a solution with a ".show-hide-columns-button" style lookup and adding an event filter. However that was 2 years ago, maybe things changed.

Thank you very much!

This is how I'd like to have it, demonstrated via ContextMenu (i. e. right mouse button click on table):

public class TableViewSample extends Application {

    private final TableView table = new TableView();
    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage stage) {
        Scene scene = new Scene(new Group());
        stage.setTitle("Table View Sample");
        stage.setWidth(300);
        stage.setHeight(500);

        // create table columns
        TableColumn firstNameCol = new TableColumn("First Name");
        TableColumn lastNameCol = new TableColumn("Last Name");
        TableColumn emailCol = new TableColumn("Email");

        table.getColumns().addAll(firstNameCol, lastNameCol, emailCol);

        // add context menu
        CustomMenuItem cmi;
        ContextMenu cm = new ContextMenu();

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

            @Override
            public void handle(MouseEvent event) {
                for( Object obj: table.getColumns()) {
                    ((TableColumn) obj).setVisible(true);
                }           }

        });

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

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

            @Override
            public void handle(MouseEvent event) {
                for (Object obj : table.getColumns()) {
                    ((TableColumn) obj).setVisible(false);
                }
            }

        });

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

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

        // menu item for all columns
        for( Object obj: table.getColumns()) {

            TableColumn tableColumn = (TableColumn) obj; 

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

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

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

        // set context menu
        table.setContextMenu(cm);

        final VBox vbox = new VBox();
        vbox.setSpacing(5);
        vbox.setPadding(new Insets(10, 0, 0, 10));
        vbox.getChildren().addAll(table);

        ((Group) scene.getRoot()).getChildren().addAll(vbox);

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

Answer 1

Inspired by the solution of ControlsFX I solved the problem myself using reflection. If someone has a better idea and cleaner way without reflection, I'm all ears. I created a utils class in order to distinguish from the sample code.

import java.lang.reflect.Field;

import javafx.collections.ObservableList;
import javafx.event.EventHandler;
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.TableView;
import javafx.scene.input.MouseEvent;

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

public class TableViewUtils {

    /**
     * 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 tableView
     */
    public static void addCustomTableMenu( TableView tableView) {

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

        // get the table  header row
        TableHeaderRow tableHeaderRow = getTableHeaderRow((TableViewSkin) tableView.getSkin());

        // get context menu via reflection
        ContextMenu contextMenu = getContextMenu(tableHeaderRow);

        // 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);

        // modify the table menu
        contextMenu.getItems().clear();

        addCustomMenuItems( contextMenu, tableView);

    }

    /**
     * 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 table
     */
    private static void addCustomMenuItems( ContextMenu cm, TableView table) {

        // create new context menu
        CustomMenuItem cmi;

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

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

        });

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

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

            @Override
            public void handle(MouseEvent event) {

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

        });

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

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

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

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

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

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

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

    }

    /**
     * Find the TableHeaderRow of the TableViewSkin
     * 
     * @param tableSkin
     * @return
     */
    private static TableHeaderRow getTableHeaderRow(TableViewSkin<?> tableSkin) {

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

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

            Node node = children.get(i);

            if (node instanceof TableHeaderRow) {
                return (TableHeaderRow) node;
            }

        }
        return null;
    }

    /**
     * Get the table menu, i. e. the ContextMenu of the given TableHeaderRow via
     * reflection
     * 
     * @param headerRow
     * @return
     */
    private static ContextMenu getContextMenu(TableHeaderRow headerRow) {

        try {

            // get columnPopupMenu field
            Field privateContextMenuField = TableHeaderRow.class.getDeclaredField("columnPopupMenu");

            // make field public
            privateContextMenuField.setAccessible(true);

            // get field
            ContextMenu contextMenu = (ContextMenu) privateContextMenuField.get(headerRow);

            return contextMenu;

        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

}

Example usage:

import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.VBox;
import javafx.scene.text.Text;
import javafx.stage.Stage;

public class CustomTableMenuDemo extends Application {

    private final ObservableList<Person> data =
            FXCollections.observableArrayList( 
            new Person("Jacob", "Smith", "[email protected]"),
            new Person("Isabella", "Johnson", "[email protected]"),
            new Person("Ethan", "Williams", "[email protected]"),
            new Person("Emma", "Jones", "[email protected]"),
            new Person("Isabella", "Johnson", "[email protected]"),
            new Person("Ethan", "Williams", "[email protected]"),
            new Person("Emma", "Jones", "[email protected]"),
            new Person("Isabella", "Johnson", "[email protected]"),
            new Person("Ethan", "Williams", "[email protected]"),
            new Person("Emma", "Jones", "[email protected]"),
            new Person("Isabella", "Johnson", "[email protected]"),
            new Person("Ethan", "Williams", "[email protected]"),
            new Person("Emma", "Jones", "[email protected]"),
            new Person("Isabella", "Johnson", "[email protected]"),
            new Person("Ethan", "Williams", "[email protected]"),
            new Person("Emma", "Jones", "[email protected]"),
            new Person("Isabella", "Johnson", "[email protected]"),
            new Person("Ethan", "Williams", "[email protected]"),
            new Person("Emma", "Jones", "[email protected]"),
            new Person("Michael", "Brown", "[email protected]"));

    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);

        // create table columns
        TableColumn<Person, String> firstNameCol = new TableColumn<Person, String>("First Name");
        firstNameCol.setMinWidth(100);
        firstNameCol.setCellValueFactory(new PropertyValueFactory<Person, String>("firstName"));

        TableColumn<Person, String> lastNameCol = new TableColumn<Person, String>("Last Name");
        lastNameCol.setMinWidth(100);
        lastNameCol.setCellValueFactory(new PropertyValueFactory<Person, String>("lastName"));

        TableColumn<Person, String> emailCol = new TableColumn<Person, String>("Email");
        emailCol.setMinWidth(180);
        emailCol.setCellValueFactory(new PropertyValueFactory<Person, String>("email"));


        TableView<Person> tableView = new TableView<>();
        tableView.setPlaceholder(new Text("No content in table"));
        tableView.setItems(data);
        tableView.getColumns().addAll(firstNameCol, lastNameCol, emailCol);

        final VBox vbox = new VBox();
        vbox.setSpacing(5);
        vbox.setPadding(new Insets(10, 10, 10, 10));

        BorderPane borderPane = new BorderPane();
        borderPane.setCenter( tableView);

        vbox.getChildren().addAll( borderPane);

        Scene scene = new Scene( vbox);


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

        // enable table menu button and add a custom menu to it
        TableViewUtils.addCustomTableMenu(tableView);
    }


    public static class Person {

        private final SimpleStringProperty firstName;
        private final SimpleStringProperty lastName;
        private final SimpleStringProperty email;

        private Person(String fName, String lName, String email) {
            this.firstName = new SimpleStringProperty(fName);
            this.lastName = new SimpleStringProperty(lName);
            this.email = new SimpleStringProperty(email);
        }

        public String getFirstName() {
            return firstName.get();
        }

        public void setFirstName(String fName) {
            firstName.set(fName);
        }

        public String getLastName() {
            return lastName.get();
        }

        public void setLastName(String fName) {
            lastName.set(fName);
        }

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

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

}

Screenshots:

Custom table menu in action, the menu remains open while you click the buttons:

Custom table menu still available, even though no columns are visible:

Edit: And here's a version that instead of reflection uses some heuristic and replaces the internal mouse event handler (see the source of JavaFX's TableHeaderRow class if you want to know more):

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.TableView;
import javafx.scene.input.MouseEvent;

import