FXML: Bind to nested field - javafx

Question

I have a TableColumn coded as:
<TableColumn text="Nom" prefWidth="${purchasesTable.width*0.65}">
<cellValueFactory>
<PropertyValueFactory property="item.name" />
</cellValueFactory>
</TableColumn>
it's TableView's items property is bound to a list of Purchase class:
Purchase class:
public class Purchase {
private Item item;
public Item getItem() {
return item;
}
public void setItem(Item item) {
this.item = item;
}
}
My Item class is as follows:
public class Item {
private long id;
private StringProperty name = new SimpleStringProperty();
private DoubleProperty price = new SimpleDoubleProperty();
//Getters and Setters
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
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);
}
}
when I add Purchases to my table the name cell do not appear. What am I doing wrong? and is it necessary to my Item fields as properties, because I want to use them somewhere else where JavaFX is not used?

Answer 1

PropertyValueFactory does not support "properties of properties". You need to implement the Callback yourself here, which has to be done in the controller class:
public class MyController {
#FXML
private TableColumn<Purchase, String> nameColumn ;
public void initialize() {
nameColumn.setCellValueFactory(cellData -> {
String name ;
Purchase purchase = cellData.getValue();
if (purchase == null) {
name = null ;
} else {
name = purchase.getName();
}
return new SimpleStringProperty(name);
});
// ...
}
// ...
}
and then in the fxml, of course, you need to map the table column to the field in the controller
<TableColumn fx:id="nameColumn" text="Nom" prefWidth="${purchasesTable.width*0.65}" />