JavaFX getting cell value on hover - javafx

Question

I was searching for a solution on how to get cell values by hovering over them, but haven't found any. I was thinking of a similar solution to this:
Can't select different cells in same row of tableview JavaFx , except not selecting, but only hover. How could I do it? Thanks.

Answer 1

Use a custom cell that updates a property when the mouse enters/exits it:
public class HoverCell extends TableCell<Person, String> {
public HoverCell(StringProperty hoverProperty) {
setOnMouseEntered(e -> hoverProperty.set(getItem()));
setOnMouseExited(e -> hoverProperty.set(null));
}
#Override
protected void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
setText(empty ? null : item);
}
}
Complete example:
import java.util.function.Function;
import javafx.application.Application;
import javafx.beans.property.Property;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
public class HoverTableCells extends Application {
#Override
public void start(Stage primaryStage) {
TableView<Person> table = new TableView<>();
TableColumn<Person, String> firstNameCol = column("First Name", Person::firstNameProperty);
TableColumn<Person, String> lastNameCol = column("Last Name", Person::lastNameProperty);
TableColumn<Person, String> emailCol = column("Email", Person::emailProperty);
StringProperty hoveredProperty = new SimpleStringProperty();
firstNameCol.setCellFactory(tc -> new HoverCell(hoveredProperty));
lastNameCol.setCellFactory(tc -> new HoverCell(hoveredProperty));
emailCol.setCellFactory(tc -> new HoverCell(hoveredProperty));
Label currentHover = new Label();
currentHover.textProperty().bind(hoveredProperty);
table.getColumns().add(firstNameCol);
table.getColumns().add(lastNameCol);
table.getColumns().add(emailCol);
table.getItems().addAll(
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")
);
BorderPane root = new BorderPane(table);
BorderPane.setMargin(currentHover, new Insets(10));
root.setTop(currentHover);
Scene scene = new Scene(root, 600, 600);
primaryStage.setScene(scene);
primaryStage.show();
}
private static <S,T> TableColumn<S,T> column(String title, Function<S, Property<T>> property) {
TableColumn<S, T> col = new TableColumn<>(title);
col.setCellValueFactory(cellData -> property.apply(cellData.getValue()));
return col ;
}
public static class HoverCell extends TableCell<Person, String> {
public HoverCell(StringProperty hoverProperty) {
setOnMouseEntered(e -> hoverProperty.set(getItem()));
setOnMouseExited(e -> hoverProperty.set(null));
}
#Override
protected void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
setText(empty ? null : item);
}
}
public static class Person {
private final StringProperty firstName = new SimpleStringProperty();
private final StringProperty lastName = new SimpleStringProperty();
private final StringProperty email = new SimpleStringProperty();
public Person(String firstName, String lastName, String email) {
setFirstName(firstName);
setLastName(lastName);
setEmail(email);
}
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 static void main(String[] args) {
launch(args);
}
}