Question

我正在尝试更改TextFieldTreeTableCell的呈现，以将字符串显示为超链接而不是纯文本，但无济于事。好像它应该可以使用setSkin，但类似

setSkin（（new HyperLink（））。getSkin（））;

或

setSkin（（new HyperLink（getItem（）））。getSkin（））;

无济于事。有关如何做到这一点的任何见解？

Answer 1

你做错了什么

您没有使用正确的功能来自定义您的单元格：setSkin用于创建自定义控件外观，并且通用于各种控件而不仅仅是单元格，您应该使用单元格工厂。< / LI>
您没有使用正确的超类：TextFieldTreeTableCell用于创建一个单元格，该单元格包含一个标签，当您单击它时可以将其制作成可编辑的TextField。当您想要“显示不可编辑的，可点击的URL”时，此功能无用。

方法你应该使用

细胞具有控制其呈现的特定方法，其在处理细胞时优于皮肤机制。这种特定于细胞的机制称为细胞工厂，并在Cell documentation中记录了一个例子。

TreeTableColumns允许您在列上set a cell factory来控制列单元格的渲染。在单元格中呈现超链接的相关代码如下：

emailColumn.setCellFactory(param -> new TreeTableCell<Employee, String>() {
    private Hyperlink link = new Hyperlink();
    {
        setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
    }

    @Override
    protected void updateItem(String item, boolean empty) {
        super.updateItem(item, empty);

        if (item == null || empty) {
            setGraphic(null);
            return;
        }

        link.setText(item);
        link.setVisited(getTreeTableRow().getItem().isVisited());
        link.setOnAction(event -> {
            getTreeTableRow().getItem().setVisited(true);
            sendLabel.setText("Send mail to: " + item);
        });
        setGraphic(link);
    }
});

示例应用

在下面的屏幕截图中，用户刚刚链接了anna.black@example.com的超链接。

示例代码是Oracle TreeTableView tutorial代码的修改版本。为了跟踪单击TreeTableView中的哪些项目，必须向Employee类添加一个访问属性，以便在更新单元格时适当地设置Hyperlink visited属性。

import javafx.application.Application;
import javafx.beans.property.*;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.image.*;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

import java.util.*;

public class TreeTableViewSample extends Application {

    private List<Employee> employees = Arrays.asList(
        new Employee("Ethan Williams", "ethan.williams@example.com"),
        new Employee("Emma Jones", "emma.jones@example.com"),
        new Employee("Michael Brown", "michael.brown@example.com"),
        new Employee("Anna Black", "anna.black@example.com"),
        new Employee("Rodger York", "roger.york@example.com"),
        new Employee("Susan Collins", "susan.collins@example.com"));

    private final ImageView depIcon = new ImageView (
            new Image("http://icons.iconarchive.com/icons/custom-icon-design/flatastic-10/16/Bear-icon.png")
    );

    final TreeItem<Employee> root = 
        new TreeItem<>(new Employee("Sales Department", ""), depIcon);
    public static void main(String[] args) {
        Application.launch(TreeTableViewSample.class, args);
    }

    final Label sendLabel = new Label();

    @Override
    public void start(Stage stage) {
        root.setExpanded(true);
        employees.forEach((employee) -> root.getChildren().add(new TreeItem<>(employee)));
        stage.setTitle("Tree Table View Sample");
        final Scene scene = new Scene(new VBox(), 400, 400);
        scene.setFill(Color.LIGHTGRAY);
        VBox sceneRoot = (VBox) scene.getRoot();

        TreeTableColumn<Employee, String> empColumn = 
            new TreeTableColumn<>("Employee");
        empColumn.setPrefWidth(150);
        empColumn.setCellValueFactory(
            (TreeTableColumn.CellDataFeatures<Employee, String> param) -> 
            new ReadOnlyStringWrapper(param.getValue().getValue().getName())
        );

        TreeTableColumn<Employee, String> emailColumn = 
            new TreeTableColumn<>("Email");
        emailColumn.setPrefWidth(190);
        emailColumn.setCellValueFactory(
            (TreeTableColumn.CellDataFeatures<Employee, String> param) -> 
            new ReadOnlyStringWrapper(param.getValue().getValue().getEmail())
        );
        emailColumn.setCellFactory(param -> new TreeTableCell<Employee, String>() {
            private Hyperlink link = new Hyperlink();
            {
                setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
            }

            @Override
            protected void updateItem(String item, boolean empty) {
                super.updateItem(item, empty);

                if (item == null || empty) {
                    setGraphic(null);
                    return;
                }

                link.setText(item);
                link.setVisited(getTreeTableRow().getItem().isVisited());
                link.setOnAction(event -> {
                    getTreeTableRow().getItem().setVisited(true);
                    sendLabel.setText("Send mail to: " + item);
                });
                setGraphic(link);
            }
        });

        TreeTableView<Employee> treeTableView = new TreeTableView<>(root);
        treeTableView.getColumns().setAll(empColumn, emailColumn);
        sceneRoot.getChildren().addAll(treeTableView, sendLabel);
        stage.setScene(scene);
        stage.show();
    }

    public class Employee {
        private SimpleStringProperty name;
        private SimpleStringProperty email;
        private SimpleBooleanProperty visited;

        public SimpleStringProperty nameProperty() {
            if (name == null) {
                name = new SimpleStringProperty(this, "name");
            }
            return name;
        }
        public SimpleStringProperty emailProperty() {
            if (email == null) {
                email = new SimpleStringProperty(this, "email");
            }
            return email;
        }
        private Employee(String name, String email) {
            this.name = new SimpleStringProperty(name);
            this.email = new SimpleStringProperty(email);
            this.visited = new SimpleBooleanProperty(false);
        }
        public String getName() {
            return name.get();
        }
        public void setName(String fName) {
            name.set(fName);
        }
        public String getEmail() {
            return email.get();
        }
        public void setEmail(String fName) {
            email.set(fName);
        }

        public void setVisited(boolean visited) {
            this.visited.set(visited);
        }

        public boolean isVisited() {
            return visited.get();
        }
    }
}

在JavaFX中覆盖TreeTableCell渲染

1 个答案: