Question

我有一个tableView，其中每个表行代表一个对象，每列代表该对象的属性。在tableView中，我定义了一个setRowFactory。

在setRowFactory中，我希望能够访问该行中的特定单元格并通过执行以下操作突出显示它：ThisCellofThisRow.pseudoClassStateChanged(...)

问题是：我不知道如何引用此ThisCellofThisRow。

Answer 1

不确定您想要做什么，但您可以更改行的伪类状态，然后使用CSS选择特定列。这样行工厂根本不必访问单元。

示例：

高亮细胞在-row.css：

/*
** Gives a yellow background to a table cell with style class "value-cell"
** that is inside a row with the "high" psuedoclass set 
*/

.table-row-cell:high .value-cell {
    -fx-background-color: transparent, yellow ;
}

TableViewHighlightItem.java：

import java.util.Random;
import java.util.function.Function;

import javafx.application.Application;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.ReadOnlyBooleanProperty;
import javafx.beans.property.ReadOnlyBooleanWrapper;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.css.PseudoClass;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableRow;
import javafx.scene.control.TableView;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;


public class TableViewHighlightItem extends Application {

    @Override
    public void start(Stage primaryStage) {

        // create table and columns:
        TableView<Item> table = new TableView<>();
        TableColumn<Item, String> nameCol = column("Name", Item::nameProperty);
        TableColumn<Item, Number> valueCol = column("Value", Item::valueProperty);
        table.getColumns().add(nameCol);
        table.getColumns().add(valueCol);

        // basic default cell, but with "value-cell" always added as a CSS class:
        valueCol.setCellFactory(col -> {
            TableCell<Item, Number> cell = new TableCell<Item, Number>(){
                @Override
                public void updateItem(Number value, boolean empty) {
                    super.updateItem(value, empty);
                    if (empty) {
                        setText(null);
                    } else {
                        setText(value.toString());
                    }
                }
            };
            cell.getStyleClass().add("value-cell");
            return cell ;
        });

        PseudoClass high = PseudoClass.getPseudoClass("high");

        // Table row toggles "high" pseudoclass according to state of current item in row:
        table.setRowFactory(tv -> {
            TableRow<Item> row = new TableRow<>();

            ChangeListener<Boolean> highListener = (obs, wasHigh, isNowHigh) -> 
                row.pseudoClassStateChanged(high, isNowHigh);

            row.itemProperty().addListener((obs, oldItem, newItem) -> {
                if (oldItem != null) {
                    oldItem.highProperty().removeListener(highListener);
                }
                if (newItem == null) {
                    row.pseudoClassStateChanged(high, false);
                } else {
                    row.pseudoClassStateChanged(high, newItem.isHigh());
                    newItem.highProperty().addListener(highListener);
                }
            });

            return row ;
        });

        Random rng = new Random();

        // Button to test changing data to random values:
        Button changeButton = new Button("Change Data");
        changeButton.setOnAction(e -> 
                table.getItems().forEach(item -> item.setValue(rng.nextInt(20))));

        // add data to table:
        for (int i = 1 ; i <= 40 ; i++) {
            table.getItems().add(new Item("Item "+i, rng.nextInt(20)));
        }

        // layout:
        BorderPane root = new BorderPane(table, null, null, changeButton, null);
        BorderPane.setAlignment(changeButton, Pos.CENTER);
        BorderPane.setMargin(changeButton, new Insets(10));
        Scene scene = new Scene(root, 600, 600);
        scene.getStylesheets().add("highlight-cell-in-row.css");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    // utility method for creating columns:
    private static <S,T> TableColumn<S,T> column(String title, Function<S, ObservableValue<T>> property) {
        TableColumn<S,T> column = new TableColumn<>(title);
        column.setCellValueFactory(cellData -> property.apply(cellData.getValue()));
        return column ;
    }

    // model class:
    public static class Item {
        private final StringProperty name = new SimpleStringProperty();
        private final IntegerProperty value = new SimpleIntegerProperty();
        private final ReadOnlyBooleanWrapper high = new ReadOnlyBooleanWrapper();

        public Item(String name, int value) {
            setName(name);
            setValue(value);
            high.bind(this.value.greaterThanOrEqualTo(10));
        }

        public final StringProperty nameProperty() {
            return this.name;
        }

        public final String getName() {
            return this.nameProperty().get();
        }

        public final void setName(final String name) {
            this.nameProperty().set(name);
        }

        public final IntegerProperty valueProperty() {
            return this.value;
        }

        public final int getValue() {
            return this.valueProperty().get();
        }

        public final void setValue(final int value) {
            this.valueProperty().set(value);
        }

        public final ReadOnlyBooleanProperty highProperty() {
            return this.high.getReadOnlyProperty();
        }

        public final boolean isHigh() {
            return this.highProperty().get();
        }


    }

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

Javafx：我如何引用setRowFactory中一行中的特定单元格？

1 个答案: