如何根据 javafx 中的 Action 为同一个 tableview 提供上下文菜单？

Question

我有一个组合框和一个 table。组合框有两个项目，它们是 type1 和 type2。当我 select 来自组合的 type1 时，table 上下文菜单显示 "type1 menu"，当我 select 来自组合的 type2 时，table 上下文菜单显示 "type2 menu"。如何弄清楚这个数字？这是我的实验代码....但它不能正常工作..!

    import java.util.Arrays;

import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.beans.property.SimpleStringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.geometry.Insets;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.ComboBox;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.Label;
import javafx.scene.control.MenuItem;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableRow;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.layout.VBox;
import javafx.scene.text.Font;
import javafx.stage.Stage;


public class TableViewSample extends Application {

    private final TableView<Person> table = new TableView<>();
    private final ComboBox<String> combo = new ComboBox<>();
    private final ObservableList<Person> data =
        FXCollections.observableArrayList(
            new Person("Jacob", "Smith", "jacob.smith@example.com"),
            new Person("Isabella", "Johnson", "isabella.johnson@example.com"),
            new Person("Ethan", "Williams", "ethan.williams@example.com"),
            new Person("Emma", "Jones", "emma.jones@example.com"),
            new Person("Michael", "Brown", "michael.brown@example.com")
        );

    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(450);
        stage.setHeight(500);

        final Label label = new Label("Right Click a table Row");
        label.setFont(new Font("Arial", 20));

        combo.getItems().setAll("Type1","Type2");
        combo.getSelectionModel().select(0);

        table.setEditable(true);

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

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

        TableColumn<Person, String> emailCol = new TableColumn<>("Email");
        emailCol.setMinWidth(200);
        emailCol.setCellValueFactory(
                new PropertyValueFactory<>("email"));

        table.setItems(data);
        table.getColumns().addAll(Arrays.asList(firstNameCol, lastNameCol, emailCol));

        setTableMenu(0);  // You Can Comment This //

        combo.setOnAction(event -> {
            setTableMenu(combo.getSelectionModel().getSelectedIndex());
        });

        //-------------------------- Final Works ------------------------------//
        final VBox vbox = new VBox();
        vbox.setSpacing(5);
        vbox.setPadding(new Insets(10, 0, 0, 10));
        vbox.getChildren().addAll(label, combo, table);

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

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

    //---------- Set What ContextMenu according to the combobox -----------//
    private void setTableMenu(int selectedIndex) {
         table.setRowFactory((TableView<Person> tableView) -> {
            final TableRow<Person> row = new TableRow<>();
            switch(selectedIndex){
                case 0:
                    final ContextMenu contextMenu1 = new ContextMenu();
                    final MenuItem item1 = new MenuItem("Type1 menu");
                    item1.setOnAction((ActionEvent event) -> {
                        System.out.println("Type 1 menu selected");
                    });
                    contextMenu1.getItems().add(item1);

                    // Set context menu on row, but use a binding to make it only show for non-empty rows:
                    row.contextMenuProperty().bind(
                            Bindings.when(row.emptyProperty())
                            .then((ContextMenu) null)
                            .otherwise(contextMenu1)
                    );
                    break;
                 case 1:
                     final ContextMenu contextMenu2 = new ContextMenu();
                     final MenuItem item2 = new MenuItem("Type2 menu");
                     item2.setOnAction((ActionEvent event) -> {
                         System.out.println("Type 2 menu selected");
                     });
                     contextMenu2.getItems().add(item2);

                     // Set context menu on row, but use a binding to make it only show for non-empty rows:
                     row.contextMenuProperty().bind(
                             Bindings.when(row.emptyProperty())
                             .then((ContextMenu) null)
                             .otherwise(contextMenu2)
                     );
             }                     
            return row ;  
        });  
    }


    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);
        }
    }


}

Answer 1

更改 rowFactory 不会更新 TableRow。这些行仍将是最初创建的行 rowFactory 并且上下文菜单的类型在创建行时决定并且永远不会更改。

然而，您可以在 ContextMenu 显示之前准备它，并根据 ComboBox 的状态对其进行修改：

// in start method
table.setRowFactory((TableView<Person> tableView) -> {
    final TableRow<Person> row = new TableRow<>();
    final ContextMenu contextMenu = new ContextMenu();

    final MenuItem item1 = new MenuItem("Type1 menu");
    item1.setOnAction((ActionEvent event) -> {
        System.out.println("Type 1 menu selected");
    });

    contextMenu.getItems().add(item1);

    final MenuItem item2 = new MenuItem("Type2 menu");
    item2.setOnAction((ActionEvent event) -> {
        System.out.println("Type 2 menu selected");
    });

    row.contextMenuProperty().bind(
            Bindings.when(row.emptyProperty())
            .then((ContextMenu) null)
            .otherwise(contextMenu)
    );

    row.setOnContextMenuRequested(evt -> {
        // update menu when requested
        switch (combo.getSelectionModel().getSelectedIndex()) {
            case 0:
                contextMenu.getItems().setAll(item1);
                break;
            case 1:
                contextMenu.getItems().setAll(item2);
                break;
        }
    });

    return row;
});

/*setTableMenu(0);

combo.setOnAction(event -> {
    setTableMenu(combo.getSelectionModel().getSelectedIndex());
});*/

或者，您也可以对所有行使用相同的 ContextMenu，并在 ComboBox:

中的更改中修改它

// in start method
final MenuItem item1 = new MenuItem("Type1 menu");
item1.setOnAction((ActionEvent event) -> {
    System.out.println("Type 1 menu selected");
});

final ContextMenu contextMenu = new ContextMenu(item1);

final MenuItem item2 = new MenuItem("Type2 menu");
item2.setOnAction((ActionEvent event) -> {
    System.out.println("Type 2 menu selected");
});

combo.setOnAction(evt -> {
    switch (combo.getSelectionModel().getSelectedIndex()) {
        case 0:
            contextMenu.getItems().setAll(item1);
            break;
        case 1:
            contextMenu.getItems().setAll(item2);
            break;
    }
});

table.setRowFactory((TableView<Person> tableView) -> {
    final TableRow<Person> row = new TableRow<>();

    row.contextMenuProperty().bind(
            Bindings.when(row.emptyProperty())
            .then((ContextMenu) null)
            .otherwise(contextMenu)
    );

    return row;
});

/*setTableMenu(0);

combo.setOnAction(event -> {
    setTableMenu(combo.getSelectionModel().getSelectedIndex());
});*/

如何根据 javafx 中的 Action 为同一个 tableview 提供上下文菜单？

How to give a Contextmenu to same tableview according to Action in javafx?

combobox

javafx

contextmenu

uitableview

tableview