Scala JavaFx -- Cannot resolve overloaded method 'add' when trying to add tree table columns - scala

Question

I am trying to write an application using JavaFX and Scala (not ScalaFX). When I tried out this example from http://tutorials.jenkov.com/javafx/treetableview.html (Add TreeTableColumn to TreeTableView), I got a "Cannot resolve overloaded method 'add'" in the last two lines. I was wondering if you can help me get past this issue.
class Phase1 extends Application {
import javafx.scene.control.TreeTableColumn
import javafx.scene.control.TreeTableView
import javafx.scene.control.cell.TreeItemPropertyValueFactory
override def start(primaryStage: Stage): Unit = {
primaryStage.setTitle("Experimental Blocking Tree")
val scene = new Scene(new Group(), 1500, 800)
val sceneRoot = scene.getRoot.asInstanceOf[Group]
val treeTableView = new TreeTableView[Car]
val treeTableColumn1: TreeTableColumn[Car, String] = new TreeTableColumn[Car, String]("Brand")
val treeTableColumn2: TreeTableColumn[Car, String] = new TreeTableColumn[Car, String]("Model")
treeTableColumn1.setCellValueFactory(new TreeItemPropertyValueFactory[Car, String]("brand"))
treeTableColumn2.setCellValueFactory(new TreeItemPropertyValueFactory[Car, String]("model"))
treeTableView.getColumns.add(treeTableColumn1) // cannot resolve overloaded method here
treeTableView.getColumns.add(treeTableColumn2) // and here
}
}
Thanks in advance.

Answer 1

I had the same issue with displaying data in TreeTableView.
Jarek posted a solution here: GitHub Issue
Also this works for me:
import scalafx.beans.property.ReadOnlyStringProperty
case class Car (
val brand: ReadOnlyStringProperty,
val model: ReadOnlyStringProperty
)
class CarStringFactory(val stringValue: ReadOnlyStringProperty) extends scalafx.beans.value.ObservableValue[String, String] {
override def delegate: javafx.beans.value.ObservableValue[String] = stringValue
override def value: String = stringValue.get
}
class YourScalaFXApp {
// ... boilerplate code ...
import scalafx.scene.control.{TreeTableView, TreeTableColumn}
val treeTableView = new TreeTableView[Car]
val treeTableColumn1: TreeTableColumn[Car, String] = new TreeTableColumn[Car, String]("Brand"){
cellValueFactory = {p => new CarStringFactory(p.value.value.value.brand) }
}
val treeTableColumn2: TreeTableColumn[Car, String] = new TreeTableColumn[Car, String]("Model"){
cellValueFactory = {p => new CarStringFactory(p.value.value.value.model) }
}
treeTableView.getColumns.add(treeTableColumn1)
treeTableView.getColumns.add(treeTableColumn2)
}
Refer to
ScalaFX documentation: Properties
TreeTableColumn.cellValueFactory