Unable to add items to Combobox

Question

I tried adding items to a combobox through the FXML file, but I get this error.

    javafx.fxml.LoadException: String is not a valid type.
/C:/Users/kim/Desktop/JavaFX/ComboboxFx/bin/application/Main.fxml:13

    at javafx.fxml.FXMLLoader.constructLoadException(Unknown Source)
    at javafx.fxml.FXMLLoader.createElement(Unknown Source)
    at javafx.fxml.FXMLLoader.processStartElement(Unknown Source)
    at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
    at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
    at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
    at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
    at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
    at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
    at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
    at javafx.fxml.FXMLLoader.load(Unknown Source)
    at application.Main.start(Main.java:13)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$162(Unknown Source)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$175(Unknown Source)
    at com.sun.javafx.application.PlatformImpl.lambda$null$173(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(Unknown Source)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$148(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

Here's my FXML

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.collections.FXCollections?>
<?import javafx.scene.control.ComboBox?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.AnchorPane?>

<AnchorPane prefHeight="300.0" prefWidth="300.0" xmlns="http://javafx.com/javafx/8.0.65" xmlns:fx="http://javafx.com/fxml/1" >
   <children>
      <ComboBox fx:id="comboBox">
        <items>
            <FXCollections fx:factory="observableArrayList">
                <String fx:value = "Gilbert" />
                <String fx:value = "John" />
            </FXCollections>
        </items>
      </ComboBox>
      <Label fx:id="selection" layoutX="34.0" layoutY="65.0" prefHeight="17.0" prefWidth="102.0" text="Label" />
   </children>
</AnchorPane>

The main

package application;

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.stage.Stage;
import javafx.scene.Parent;
import javafx.scene.Scene;

public class Main extends Application {
    @Override
    public void start(Stage primaryStage) {
        try {
            Parent root = FXMLLoader.load(getClass().getResource("/application/Main.fxml"));
            Scene scene = new Scene(root,400,400);
            scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
            primaryStage.setScene(scene);
            primaryStage.show();
        } catch(Exception e) {
            e.printStackTrace();
        }
    }

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

I get this error when I open it through scene builder

java.io.IOException: javafx.fxml.LoadException: Invalid attribute.

I've double checked everything but the code seems fine. The error goes away when I remove the values I'm trying to add to the FXML, but my combobox becomes empty. It says String is not a valid type. How can I solve this problem? And why is it invalid? I've checked similar questions here, but the errors are caused by not importing FXCollections. I imported it so I think the error is not caused by bad import.

Answer 1

Add

<?import java.lang.String?>

to your fxml.