Question

我想使用箭头/输入键来遍历TableView中的单元格，但是，如果我尝试在自定义EditCell类中实现它，则似乎无法正常工作。有没有办法做到这一点？我在TextField上尝试了一个侦听器，但实际上并没有在实际单元格中开始聚焦。

这是我的代码：

Tester.java

package tester;

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableRow;
import javafx.scene.control.TableView;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
import javafx.util.Callback;

public class Tester extends Application
{

    @Override
    public void start(Stage primaryStage)
    {

        TableView<LineItem> table = new TableView<>();

        Callback<TableColumn<LineItem, String>, TableCell<LineItem, String>> textFactoryEditable = (TableColumn<LineItem, String> p) -> new EditableTextCell();

        TableColumn<LineItem, String> column1 = new TableColumn<>("Test1");
        column1.setCellValueFactory(cellData -> cellData.getValue().getString1Property());
        column1.setEditable(true);
        column1.setCellFactory(textFactoryEditable);

        table.getColumns().add(column1);

        TableColumn<LineItem, String> column2 = new TableColumn<>("Test2");
        column2.setCellValueFactory(cellData -> cellData.getValue().getString2Property());
        column2.setEditable(true);
        column2.setCellFactory(textFactoryEditable);

        table.getColumns().add(column2);

        table.getItems().add(new LineItem());
        table.getItems().add(new LineItem());
        table.getItems().add(new LineItem());

        table.setPrefWidth(500);

        HBox root = new HBox();
        root.getChildren().addAll(table);

        Scene scene = new Scene(root, 500, 500);

        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)
    {
        launch(args);
    }

}

LineItem.java

package tester;

import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;

public class LineItem
{

    private final StringProperty string1;
    private final StringProperty string2;

    public LineItem()
    {
        this.string1 = new SimpleStringProperty();
        this.string2 = new SimpleStringProperty();
    }

    public final StringProperty getString1Property()
    {
        return this.string1;
    }

    public final StringProperty getString2Property()
    {
        return this.string2;
    }
}

EditableTextCell.java

package tester;

import java.util.Objects;
import javafx.beans.value.ObservableValue;
import javafx.beans.value.WritableValue;
import javafx.geometry.Pos;
import javafx.scene.control.TableCell;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyEvent;

public class EditableTextCell<E> extends TableCell<E, String>
{

    private final TextField textField;
    private boolean updating = false;

    public EditableTextCell()
    {
        textField = new TextField();
        textField.setAlignment(Pos.CENTER_RIGHT);


        textField.textProperty().addListener((ObservableValue<? extends String> o, String oldValue, String newValue) ->
        {

            if (!updating)
            {
                ((WritableValue<String>) getTableColumn().getCellObservableValue((E) getTableRow().getItem())).setValue(newValue);
                getTableView().scrollTo(getTableRow().getIndex());
                getTableView().scrollToColumn(getTableColumn());
            }

        });

        textField.setOnKeyPressed((KeyEvent ke) ->
        {
            switch (ke.getCode())
            {
                case DOWN:
                    getTableView().getFocusModel().focusBelowCell();
                    break;
                case UP:
                    getTableView().getFocusModel().focusAboveCell();
                    break;
                case RIGHT:
                    getTableView().getFocusModel().focusRightCell();
                    break;
                case LEFT:
                    getTableView().getFocusModel().focusLeftCell();
                    break;
                default:
                    break;
            }
        });

    }

    @Override
    protected void updateItem(String item, boolean empty)
    {
        super.updateItem(item, empty);
        if (empty)
        {
            setGraphic(null);
        } else
        {
            setGraphic(textField);
            if (!Objects.equals(textField.getText(), item))
            {
                // prevent own updates from moving the cursor
                updating = true;
                textField.setText(item);
                updating = false;

            }
        }
    }
}

Answer 1

行选择模式

尽管my comment，但您似乎不需要为此启用cell selection。从CheckBoxTableCell的实现中汲取灵感，您的自定义TableCell应该采取某种形式的回调来获取模型属性；它也可能需要StringConverter，使您可以将TableCell不仅用于String。这是一个示例：

import java.util.Objects;
import java.util.function.IntFunction;
import javafx.beans.binding.Bindings;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.Property;
import javafx.beans.property.SimpleObjectProperty;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView.TableViewFocusModel;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyEvent;
import javafx.util.Callback;
import javafx.util.StringConverter;
import javafx.util.converter.DefaultStringConverter;

public class CustomTableCell<S, T> extends TableCell<S, T> {

    public static <S> Callback<TableColumn<S, String>, TableCell<S, String>> forTableColumn(
            IntFunction<Property<String>> extractor) {
        return forTableColumn(extractor, new DefaultStringConverter());
    }

    public static <S, T> Callback<TableColumn<S, T>, TableCell<S, T>> forTableColumn(
            IntFunction<Property<T>> extractor, StringConverter<T> converter) {
        Objects.requireNonNull(extractor);
        Objects.requireNonNull(converter);
        return column -> new CustomTableCell<>(extractor, converter);
    }

    private final ObjectProperty<IntFunction<Property<T>>> extractor = new SimpleObjectProperty<>(this, "extractor");
    public final void setExtractor(IntFunction<Property<T>> callback) { extractor.set(callback); }
    public final IntFunction<Property<T>> getExtractor() { return extractor.get(); }
    public final ObjectProperty<IntFunction<Property<T>>> extractorProperty() { return extractor; }

    private final ObjectProperty<StringConverter<T>> converter = new SimpleObjectProperty<>(this, "converter");
    public final void setConverter(StringConverter<T> converter) { this.converter.set(converter); }
    public final StringConverter<T> getConverter() { return converter.get(); }
    public final ObjectProperty<StringConverter<T>> converterProperty() { return converter; }

    private Property<T> property;
    private TextField textField;

    public CustomTableCell(IntFunction<Property<T>> extractor, StringConverter<T> converter) {
        setExtractor(extractor);
        setConverter(converter);

        // Assumes this TableCell will never become part of a different TableView
        // after the first one. Also assumes the focus model of the TableView will
        // never change. These are not great assumptions (especially the latter),
        // but this is only an example.
        tableViewProperty().addListener((obs, oldTable, newTable) ->
                newTable.getFocusModel().focusedCellProperty().addListener((obs2, oldPos, newPos) -> {
                    if (getIndex() == newPos.getRow() && getTableColumn() == newPos.getTableColumn()) {
                        textField.requestFocus();
                    }
                })
        );
    }

    @Override
    protected void updateItem(T item, boolean empty) {
        super.updateItem(item, empty);
        if (empty) {
            setText(null);
            setGraphic(null);
            cleanUpProperty();
        } else {
            initializeTextField();
            cleanUpProperty();

            property = getExtractor().apply(getIndex());
            Bindings.bindBidirectional(textField.textProperty(), property, getConverter());

            setGraphic(textField);
            if (getTableView().getFocusModel().isFocused(getIndex(), getTableColumn())) {
                textField.requestFocus();
            }
        }
    }

    private void cleanUpProperty() {
        if (property != null) {
            Bindings.unbindBidirectional(textField.textProperty(), property);
            property = null;
        }
    }

    private void initializeTextField() {
        if (textField == null) {
            textField = new TextField();
            textField.addEventFilter(KeyEvent.KEY_PRESSED, this::processArrowKeys);
            textField.focusedProperty().addListener((observable, wasFocused, isFocused) -> {
                if (isFocused) {
                    getTableView().getFocusModel().focus(getIndex(), getTableColumn());
                }
            });
        }
    }

    private void processArrowKeys(KeyEvent event) {
        if (event.getCode().isArrowKey()) {
            event.consume();

            TableViewFocusModel<S> model = getTableView().getFocusModel();
            switch (event.getCode()) {
                case UP:
                    model.focusAboveCell();
                    break;
                case RIGHT:
                    model.focusRightCell();
                    break;
                case DOWN:
                    model.focusBelowCell();
                    break;
                case LEFT:
                    model.focusLeftCell();
                    break;
                default:
                    throw new AssertionError(event.getCode().name());
            }
            getTableView().scrollTo(model.getFocusedCell().getRow());
            getTableView().scrollToColumnIndex(model.getFocusedCell().getColumn());
        }
    }

}

该示例并非详尽无遗，并做出了无法保证的假设，但这只是一个示例，因此我需要您做任何调整。这样的改进之一可能是以某种方式包含了TextFormatter。就是说，我相信它提供了您正在寻找的基本功能。

要使用此单元格，只需设置每个cellFactory的{{1}}。不必设置TableColumn，这实际上可能是有害的，具体取决于如何调用cellValueFactory。基本上，它看起来像：

updateItem

单元格选择模式

您尝试实现的这种行为似乎本质上是基于单元格的，因此启用单元格选择可能更好。这允许自定义TableView<YourModel> table = ...; TableColumn<YourModel, String> column = new TableColumn<>("Column"); column.setCellFactory(CustomTableCell.forTableColumn(i -> table.getItems().get(i).someProperty())); table.getColumns().add(column);将其行为基于选择而不是焦点，并将箭头键处理留给TableCell。这是上面示例的稍作修改的版本：

TableView

注释

使用import java.util.Objects; import java.util.function.IntFunction; import javafx.beans.binding.Bindings; import javafx.beans.property.ObjectProperty; import javafx.beans.property.Property; import javafx.beans.property.SimpleObjectProperty; import javafx.event.EventDispatcher; import javafx.scene.control.TableCell; import javafx.scene.control.TableColumn; import javafx.scene.control.TextField; import javafx.scene.input.KeyEvent; import javafx.util.Callback; import javafx.util.StringConverter; import javafx.util.converter.DefaultStringConverter; public class CustomTableCell<S, T> extends TableCell<S, T> { /* * -- CODE OMITTED -- * * The factory methods (forTableColumn) and properties (extractor * and converter) have been omitted for brevity. They are defined * and used exactly the same way as in the previous example. */ private Property<T> property; private TextField textField; public CustomTableCell(IntFunction<Property<T>> extractor, StringConverter<T> converter) { setExtractor(extractor); setConverter(converter); } @Override public void updateSelected(boolean selected) { super.updateSelected(selected); if (selected && !isEmpty()) { textField.requestFocus(); } } @Override protected void updateItem(T item, boolean empty) { super.updateItem(item, empty); if (empty) { setText(null); setGraphic(null); clearProperty(); } else { initializeTextField(); clearProperty(); property = getExtractor().apply(getIndex()); Bindings.bindBidirectional(textField.textProperty(), property, getConverter()); setGraphic(textField); if (isSelected()) { textField.requestFocus(); } } } private void clearProperty() { if (property != null) { Bindings.unbindBidirectional(textField.textProperty(), property); textField.setText(null); property = null; } } private void initializeTextField() { if (textField == null) { textField = new TextField(); textField.focusedProperty().addListener((observable, wasFocused, isFocused) -> { if (isFocused && !isSelected()) { getTableView().getSelectionModel().clearAndSelect(getIndex(), getTableColumn()); } }); /* * TableView has key handlers that will select cells based on arrow keys being * pressed, scrolling to them if necessary. I find this mechanism looks cleaner * because, unlike TableView#scrollTo, it doesn't cause the cell to jump to the * top of the TableView. * * The way this works is by bypassing the TextField if, and only if, the event * is a KEY_PRESSED event and the pressed key is an arrow key. This lets the * event bubble up back to the TableView and let it do what it needs to. All * other key events are given to the TextField for normal processing. * * NOTE: The behavior being relied upon here is added by the default TableViewSkin * and its corresponding TableViewBehavior. This may not work if a custom * TableViewSkin skin is used. */ EventDispatcher oldDispatcher = textField.getEventDispatcher(); textField.setEventDispatcher((event, tail) -> { if (event.getEventType() == KeyEvent.KEY_PRESSED && ((KeyEvent) event).getCode().isArrowKey()) { return event; } else { return oldDispatcher.dispatchEvent(event, tail); } }); } } }（并实际上选择多个行/单元格）时，两种方法都无法很好地工作。
在SelectionMode.MULTIPLE上设置的ObservableList不能定义extractor。由于某些原因，这会导致您在键入TableView时表格选择右下一个单元格。
仅使用JavaFX 12测试了这两种方法。

Answer 2

感谢Slaw弄清楚了。

首先启用单元格选择，table.getSelectionModel().setCellSelectionEnabled(true);

然后在EditableTextCell.java类中：

        this.focusedProperty().addListener((ObservableValue<? extends Boolean> o, Boolean oldValue, Boolean newValue) ->
        {
            if (newValue)
            {
                textField.requestFocus();
            }

        });

        textField.focusedProperty().addListener((ObservableValue<? extends Boolean> o, Boolean oldValue, Boolean newValue) ->
        {
            if (newValue)
            {
                getTableView().getFocusModel().focus(getTableRow().getIndex(), getTableColumn());
            }
        }


        textField.setOnKeyPressed((KeyEvent ke) ->
        {
            switch (ke.getCode())
            {
                case DOWN:
                    getTableView().getFocusModel().focusBelowCell();
                    ke.consume();
                    break;
                case ENTER:
                    getTableView().getFocusModel().focusBelowCell();
                    ke.consume();
                    break;
                case UP:
                    getTableView().getFocusModel().focusAboveCell();
                    ke.consume();
                    break;
                case RIGHT:
                    getTableView().getFocusModel().focusRightCell();
                    ke.consume();
                    break;
                case LEFT:
                    getTableView().getFocusModel().focusLeftCell();
                    ke.consume();
                    break;
                default:
                    break;
            }
        });

如何使用箭头按钮在TableView的编辑模式下遍历单元格

2 个答案:

行选择模式

单元格选择模式

注释