JavaFx fx:id causes error

javafx controller initialize
fxml

For some reason, my fx:id does not bind properly to my Controller class, and thus always causes an error.

Controller

package sample;

import javafx.fxml.FXML;

import java.awt.*;
import java.awt.event.ActionEvent;

public class Controller {

    @FXML public Button button;

    public void clickAction(ActionEvent actionEvent) {
        System.out.println("Button clicked.");
    }
}

FXML

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

<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>

<BorderPane fx:controller="sample.Controller" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1">
   <Button text="Click me!" fx:id="button" onAction="#clickAction" BorderPane.alignment="CENTER"/>
</BorderPane>

I think I understand the source of my problem, but I do not understand how to properly address it. According an answer of this question, I think I am trying to assign FXML elements before the constructor is called (and these elements can only be assigned during/after initialisation).

Is there a way to do this without implementing Initializable? Or am I making a completely different mistake?

You use the imports

<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>

in your fxml file.

Therefore the Button instance created while loading the fxml file is a javafx.scene.control.Button.

The type of the field this is injected to needs be something a javafx.scene.control.Button can be assigned to.

Since your only imports in the controller besides javafx.fxml.FXML are from the java.awt packages, this is clearly not the case for the button field (type java.awt.Button).

Fix your controller to import the required classes from the javafx packages instead:

import javafx.fxml.FXML;

import javafx.scene.control.Button;
import javafx.event.ActionEvent;

BTW: You can also leave out the parameter of the onAction handler, if you do not use it:

public void clickAction() {
    System.out.println("Button clicked.");
}

How to fix an error, when adding a controller to my FXML, You use the imports <?import javafx.scene.control.*?> <?import javafx.scene. layout.*?>. in your fxml file. Therefore the Button instance created while loading the� Extension/Filetype filter in FileSaveService not working (JavaFX 2.2 b7) RT-31486: Deployment: FileSaveService is broken from 7u25 (FX 2.2.25) RT-24960: Deployment, Packager: Window ico files causes packaging errors: RT-23778: Deployment: Native bundle - wrong main jar, wrong executable class: RT-24065: Deployment

Note that:

1)You were using the old Swing library in the import statements

2)You need to add @FXML on every method and element with id defined using fxml

Your code should be:

import javafx.fxml.FXML;
import javafx.scene.control.Button;
import javafx.event.ActionEvent;

public class Controller {

    @FXML
     public Button button;

     @FXML
    public void clickAction(ActionEvent actionEvent) {
        System.out.println("Button clicked.");
    }
}

Also mention that as Fabian and Michael said on their answers you don't need ActionEvent actionEvent into the clickAction method.So finnally:

 @FXML
        public void clickAction() {
            System.out.println("Button clicked.");
        }

Problem with javafx - Back End Help, I'm working on a JavaFX project for university, where we have to program the game "Set". I wanted to test <fx:root fx:id="omg" maxHeight="-Infinity" maxWidth ="-Infinity" Thread.run(Thread.java:835) Caused by: java.lang. I've got a rather basic JavaFx 2.x pet project which has a main window with stage and a dialog with a new Stage but using the main window as owner. I'm rather new in JavaFx and I've never used it professionally.

The only problem I see if your import of ActionEvent. You are using awt and should be using javafx ActionEvent.

import javafx.event.ActionEvent

Edit 1

You also dont need to have ActionEvent as a parameter if you dont need it, just an FYI.

Scene Builder, <?import javafx.scene.text.*?> xmlns:fx="http://javafx.com/fxml/1"> <children> < Button fx:id="btsubmit" layoutX="327.0" layoutY="33.0" The information below is the error presentation 1 more Caused by: java.lang. You are executing the someNewFunction outside the javafx loop. I mean, after the show method ends, the main thread takes control and the javafx components no longer exists (they are destroyed as is supposed that they are no longer needed).

Recently, I think I had a similar problem. FXML was giving me error. The reason was an incorrectly imported library. Instead java.scene.control , I imported java.awt .

look at the possibilities:

FXML and Controllers, While Scene Builder is a standalone application, it produces FXML files that are the latest changes in JavaFX, and also recent improvements and bug fixes. all the objects that have an fx:id in the FXML and are marked with the @FXML� However, because using a JavaFX class name as a type selector is an exact match, providing style declarations for a Shape will not cause a Rectangle to use those values (unless the .css value for the Rectangle's property is "inherit").

JavaFX issue with .fmxl file: "Cannot set javafx.scene.controller , Every child element of the <fx:define> needs a fx:id attribute. Objects created this way can be� ERROR alert :The ERROR alert type configures the Alert dialog to appear in a way that suggests that something has gone wrong. An Alert contains 3 parts: The header; The content text; The confirmation buttons; Constructors of the class are: Alert(Alert.AlertType a): Creates a new alert with a specified alert type.

Implementing JavaFX Best Practices, I'm not sure why I'm getting this error - on my MainWindowView.fxml, I get red-text … <Label fx:id="label" alignment="CENTER" layoutX="283.0" layoutY="107.0" InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95) Caused� You might need to add more FX modules to command to be able to run w/out errors, e.g. --add-modules javafx.controls,javafx.fxml,javafx.graphics.

[PDF] JavaFX, Learn best programming practices for JavaFX application design and implementation. @Override public void start(Stage stage) throws Exception { preloaderStage fx:id="heatTab" fx:controller="com.javafx.experiments.dataapp. client.heattab. If doing so would cause the user to wait a significant amount of time, you� Probably you forgot to set a controller in the FMXL (using fx:controller) or you forgot to set an fx:id of msgText for your Text node in your FXML. Note an fx:id is not the same as a css id. Note an fx:id is not the same as a css id.

Comments
  • Erhm, what error?
  • I agree. Show us your stack trace.
  • Fantastic. I guess I just hit enter without thinking when Intellij suggested my imports. Thanks!