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Java Build a JavaFX Application Design a Better App The Controller

Juneau Lim
Juneau Lim
13,362 Points
Posted by Juneau Lim
Juneau Lim
13,362 Points

"firstName" is marked as red, InvocationTargetException thrown

<!--sample.fxml-->
<?import javafx.geometry.Insets?>
<?import javafx.scene.layout.GridPane?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.text.Text?>
<?import javafx.scene.control.TextField?>
<GridPane fx:controller="sample.Controller"
          xmlns:fx="http://javafx.com/fxml" alignment="center" hgap="10" vgap="10">
    <Text text="Sup"
          GridPane.rowIndex="0"
          GridPane.columnSpan="2"
          GridPane.halignment="CENTER"/>

    <Label text="First Name:"
           GridPane.rowIndex="1"
           GridPane.columnIndex="0" />

    <TextField fx:id="firstName"     
            GridPane.rowIndex="1"
            GridPane.columnIndex="1"/>
            <!--Cannot set javafx.scene.control.TextField to field 'firstName'-->

    <Button text="Say Sup"
            onAction="#handleSaySup"
            GridPane.rowIndex="2"
            GridPane.columnIndex="1"
            GridPane.halignment="RIGHT"/>
</GridPane>

// Controller.java
package sample;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;

import java.awt.*;

public class Controller {

    @FXML private TextField firstName;

    public void handleSaySup(ActionEvent actionEvent) {
        System.out.printf("Sup %s! %n", firstName.getText());
    }
}

Not so sure where was the mistake. :-( It was ok until I added handleSaySup method

1 Answer

Steven Thomas
Steven Thomas
2,911 Points

Hey there,

I took a look at your code and I think the issue here is a missing import statement. if you add the following line on your controller I think the issue should resolve itself.

import javafx.scene.control.TextField;

Part of what is causing the confusion here is that you have a blanket import on java.awt which ALSO has a text field. This is why the IDE isn't reporting an issue with it in the controller.

Juneau Lim
Juneau Lim
13,362 Points
Juneau Lim
Juneau Lim
13,362 Points

How silly I am. Thanks a lot!

Steven Thomas
Steven Thomas
2,911 Points

No problem at all. It is a really easy mistake to make and not entirely obvious at first glance.