获取 ComboBoxTableCell 的值

Question

我使用此代码将一个 ComboBoxCell 放入我的 Table 命名为 "ComboTable"。前两列的数据由此代码下方的数据库连接给出。

 ComboTable.setEditable(true);
        col1.setCellValueFactory(new PropertyValueFactory<model, String>("rCol1"));
        col2.setCellValueFactory(new PropertyValueFactory<model, String>("rCol2"));
        col3.setCellValueFactory(new PropertyValueFactory<model, String>("rCol3"));
        col3.setCellFactory(ComboBoxTableCell.forTableColumn(cbValues));

        // ChangeListener
        ComboTable.getSelectionModel().selectedItemProperty().addListener(new ChangeListener<Object>() { 
        @Override
        public void changed (ObservableValue<?> oValue, Object oldValue, Object newValue) {
            tableIndexProperty.set(tableData.indexOf(newValue));
            tableIndex = (tableData.indexOf(newValue));
            System.out.println("Index:\t" + tableIndex);
            System.out.println(col3.getCellData(tableIndex));
        }});

所以现在我想通过使用更改侦听器在 table 中设置值后接收值。在我为组合框tablecell:

选择一个值后，我认为这段代码给了我值

System.out.println(col3.getCellData(tableIndex));

如果是我的程序，我在这部分哪里出错了，还是获取值的方式不对？

顺便说一句，这是我的程序的输出：

*** Loaded Oracle-Driver ***
*** Connected with Database ***
Index of Databaserow:   1
Daten1:  one            Daten2: two
Index of Databaserow:   2
Daten1:  tree           Daten2: four

*** Database data saved to Observable List named 'data' ***
*** Table Items setted ***

我点击了此处的 table 行 -> ChangeListener：

Index:  1
null
Index:  0
null
Index:  1
null
Index:  0
null

型号：

package model;

import controller.main_controller.ComboValues;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;

public class model {

     private StringProperty rCol1 = new SimpleStringProperty();
     private StringProperty rCol2 = new SimpleStringProperty();
     private ObjectProperty<ComboValues> rCol3 = new SimpleObjectProperty<>();


     public model(String sCol1, String sCol2, ComboValues sCol3) {
         setCol1(sCol1);
         setCol2(sCol2);
         setComboValues(sCol3);
     }

     public final StringProperty col1Property() {
         return this.rCol1;
     }

     public final String setCol1() {
         return this.col1Property().get();
     }

     public final void setCol1(final String col1) {
         this.col1Property().set(col1);
     }

     public final StringProperty col2Property() {
         return this.rCol2;
     }

     public final String setCol2() {
         return this.col2Property().get();
     }

     public final void setCol2(final String col2) {
         this.col1Property().set(col2);
     }

     public final ObjectProperty<ComboValues> combovaluesProperty() {
         return this.rCol3;
     }

     public final ComboValues getComboValues() {
         return this.combovaluesProperty().get();
     }

     public final void setComboValues(final ComboValues rCol3) {
         this.combovaluesProperty().set(rCol3);
     }

}

Answer 1

问题似乎是您尚未为该列设置 cellValueFactory，因此没有与之关联的数据。因此，当您调用 getCellData(...) 以查找单元格的值时，它（当然）是 returns null。只需在映射到模型中的列上设置一个 cellValueFactory，就像使用默认值 cellFactory 对列所做的一样。

这是一个示例，使用 Oracle 教程中的标准联系人 table：

import java.util.Arrays;

import javafx.application.Application;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.ComboBoxTableCell;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

public class TableViewWithComboColumn extends Application {

    public enum Category { Friends, Family, Work, Other }

    @Override
    public void start(Stage primaryStage) {
        TableView<Person> table = new TableView<>();
        table.setEditable(true);

        TableColumn<Person, String> firstNameCol = new TableColumn<>("First name");
        TableColumn<Person, String> lastNameCol = new TableColumn<>("Last name");
        TableColumn<Person, String> emailCol = new TableColumn<>("Email");
        TableColumn<Person, Category> categoryCol = new TableColumn<>("Category");


        firstNameCol.setCellValueFactory(cellData -> cellData.getValue().firstNameProperty());
        // or firstNameCol.setCellValueFactory(new PropertyValueFactory<>("firstName")); etc

        lastNameCol.setCellValueFactory(cellData -> cellData.getValue().lastNameProperty());
        emailCol.setCellValueFactory(cellData -> cellData.getValue().emailProperty());

        categoryCol.setCellValueFactory(cellData -> cellData.getValue().categoryProperty());
        categoryCol.setCellFactory(ComboBoxTableCell.forTableColumn(Category.values()));

        ObservableList<Person> tableData = createData();
        table.setItems(tableData);

        table.getSelectionModel().selectedItemProperty().addListener((obs, oldSelectedPerson, newSelectedPerson) -> {
            int tableIndex = tableData.indexOf(newSelectedPerson) ;
            System.out.println("Index:\t" + tableIndex);
            System.out.println(categoryCol.getCellData(tableIndex));
            // better: just get the data from the model:
            System.out.println(newSelectedPerson.getCategory());
        });

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

        primaryStage.setScene(new Scene(new BorderPane(table), 800, 600));
        primaryStage.show();

    }

    private ObservableList<Person> createData() {
        return FXCollections.observableArrayList(
            new Person("Jacob", "Smith", "jacob.smith@example.com", Category.Family),
            new Person("Isabella", "Johnson", "isabella.johnson@example.com", Category.Friends),
            new Person("Ethan", "Williams", "ethan.williams@example.com", Category.Work),
            new Person("Emma", "Jones", "emma.jones@example.com", Category.Work),
            new Person("Michael", "Brown", "michael.brown@example.com", Category.Other)
        );
    }

    public static class Person {

        private final StringProperty firstName = new SimpleStringProperty();
        private final StringProperty lastName = new SimpleStringProperty();
        private final StringProperty email = new SimpleStringProperty() ;
        private final ObjectProperty<Category> category = new SimpleObjectProperty<>();

        public Person(String firstName, String lastName, String email, Category category) {
            setFirstName(firstName);
            setLastName(lastName);
            setEmail(email);
            setCategory(category);
        }

        public final StringProperty firstNameProperty() {
            return this.firstName;
        }

        public final String getFirstName() {
            return this.firstNameProperty().get();
        }

        public final void setFirstName(final String firstName) {
            this.firstNameProperty().set(firstName);
        }

        public final StringProperty lastNameProperty() {
            return this.lastName;
        }

        public final String getLastName() {
            return this.lastNameProperty().get();
        }

        public final void setLastName(final String lastName) {
            this.lastNameProperty().set(lastName);
        }

        public final StringProperty emailProperty() {
            return this.email;
        }

        public final String getEmail() {
            return this.emailProperty().get();
        }

        public final void setEmail(final String email) {
            this.emailProperty().set(email);
        }

        public final ObjectProperty<Category> categoryProperty() {
            return this.category;
        }

        public final Category getCategory() {
            return this.categoryProperty().get();
        }

        public final void setCategory(final Category category) {
            this.categoryProperty().set(category);
        }


    }

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

获取 ComboBoxTableCell 的值

Get value of a ComboBoxTableCell

combobox

javafx

tableview