So guys I have been developing a JavaFx application that allows a user to easily add or remove entities from an H2 database. Now am trying to create a separate scene that will allow the user to enter the details of the entity each time the user clicks on the add button. But each time I try to populate the comboboxes and choiceboxes I get an exception but if I don't try to populate the boxes there is no exception.
Here is the method creating the separate scene
/**
* Method loads a new window when the add or edit button is clicked
*/
private void loadAddOrEditWindow() throws IOException {
Stage stage = new Stage();
FXMLLoader editUi = new FXMLLoader(mainUIController.class.getResource(PATH_TO_EDIT_UI));
Scene editScene = new Scene(editUi.load());
Image icon = new Image(PATH_TO_ICON);
stage.getIcons().add(icon);
stage.setTitle("JFB Students Manager");
stage.setScene(editScene);
stage.centerOnScreen();
stage.setResizable(false);
stage.initModality(Modality.APPLICATION_MODAL);
stage.show();
}
The button click that is calling the method
/**
* Method adds a single entity to the database and then refreshes the tableview
*/
public void addDataToDB() {
try {
loadAddOrEditWindow();
} catch (IOException e) {
ErrorHandler.failedToAddOrEditError();
}
System.out.println("Add to Database");
}
The separate controller for the new window
public class editUIController implements Initializable{
@FXML
public TextField firstNameField;
@FXML
public TextField lastNameField;
@FXML
public ChoiceBox<Gender> genderSelector;
@FXML
public DatePicker dateOFBirthSelector;
@FXML
public TextField phoneNumberField;
@FXML
public TextField emailField;
@FXML
public ComboBox<Nation> nationalitySelector;
@FXML
public ComboBox<CountryCodes> countryCodeSelector;
public void saveStudent() {
}
@Override
public void initialize(URL location, ResourceBundle resources) {
nationalitySelector.setItems(FXCollections.observableList(List.of(Nation.values())));
genderSelector.setItems(FXCollections.observableList(List.of(Gender.values())));
countryCodeSelector.setItems(FXCollections.observableList(List.of(CountryCodes.values())));
}
}
and finally the stack trace
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml@18.0.1/javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1857)
at javafx.fxml@18.0.1/javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1724)
at javafx.base@18.0.1/com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at javafx.base@18.0.1/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:234)
at javafx.base@18.0.1/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at javafx.base@18.0.1/com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at javafx.base@18.0.1/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at javafx.base@18.0.1/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base@18.0.1/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base@18.0.1/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base@18.0.1/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base@18.0.1/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base@18.0.1/com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at javafx.base@18.0.1/com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
at javafx.base@18.0.1/javafx.event.Event.fireEvent(Event.java:198)
at javafx.graphics@18.0.1/javafx.scene.Node.fireEvent(Node.java:8797)
at javafx.controls@18.0.1/javafx.scene.control.Button.fire(Button.java:203)
at javafx.controls@18.0.1/com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:208)
at javafx.controls@18.0.1/com.sun.javafx.scene.control.inputmap.InputMap.handle(InputMap.java:274)
at javafx.base@18.0.1/com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:247)
at javafx.base@18.0.1/com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at javafx.base@18.0.1/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:234)
at javafx.base@18.0.1/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at javafx.base@18.0.1/com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at javafx.base@18.0.1/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at javafx.base@18.0.1/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base@18.0.1/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base@18.0.1/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base@18.0.1/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base@18.0.1/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base@18.0.1/com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at javafx.base@18.0.1/com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.base@18.0.1/javafx.event.Event.fireEvent(Event.java:198)
at javafx.graphics@18.0.1/javafx.scene.Scene$MouseHandler.process(Scene.java:3881)
at javafx.graphics@18.0.1/javafx.scene.Scene.processMouseEvent(Scene.java:1874)
at javafx.graphics@18.0.1/javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2607)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:411)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:301)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$2(GlassViewEventHandler.java:450)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:424)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:449)
at javafx.graphics@18.0.1/com.sun.glass.ui.View.handleMouseEvent(View.java:551)
at javafx.graphics@18.0.1/com.sun.glass.ui.View.notifyMouse(View.java:937)
at javafx.graphics@18.0.1/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics@18.0.1/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:184)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at com.sun.javafx.reflect.Trampoline.invoke(MethodUtil.java:77)
at jdk.internal.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at javafx.base@18.0.1/com.sun.javafx.reflect.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml@18.0.1/com.sun.javafx.fxml.MethodHelper.invoke(MethodHelper.java:84)
at javafx.fxml@18.0.1/javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1854)
... 46 more
Caused by: java.lang.NullPointerException
at java.base/java.util.ImmutableCollections$ListN.indexOf(ImmutableCollections.java:716)
at javafx.base@18.0.1/com.sun.javafx.collections.ObservableListWrapper.indexOf(ObservableListWrapper.java:124)
at javafx.controls@18.0.1/javafx.scene.control.skin.ComboBoxListViewSkin.getIndexOfComboBoxValueInItemsList(ComboBoxListViewSkin.java:478)
at javafx.controls@18.0.1/javafx.scene.control.skin.ComboBoxListViewSkin.updateValue(ComboBoxListViewSkin.java:416)
at javafx.controls@18.0.1/javafx.scene.control.skin.ComboBoxListViewSkin.<init>(ComboBoxListViewSkin.java:169)
at javafx.controls@18.0.1/javafx.scene.control.ComboBox.createDefaultSkin(ComboBox.java:447)
at javafx.controls@18.0.1/javafx.scene.control.Control.doProcessCSS(Control.java:899)
at javafx.controls@18.0.1/javafx.scene.control.Control$1.doProcessCSS(Control.java:89)
at javafx.controls@18.0.1/com.sun.javafx.scene.control.ControlHelper.processCSSImpl(ControlHelper.java:67)
at javafx.graphics@18.0.1/com.sun.javafx.scene.NodeHelper.processCSS(NodeHelper.java:146)
at javafx.graphics@18.0.1/javafx.scene.Parent.doProcessCSS(Parent.java:1400)
at javafx.graphics@18.0.1/javafx.scene.Parent$1.doProcessCSS(Parent.java:125)
at javafx.graphics@18.0.1/com.sun.javafx.scene.ParentHelper.processCSSImpl(ParentHelper.java:98)
at javafx.graphics@18.0.1/com.sun.javafx.scene.NodeHelper.processCSS(NodeHelper.java:146)
at javafx.graphics@18.0.1/javafx.scene.Parent.doProcessCSS(Parent.java:1400)
at javafx.graphics@18.0.1/javafx.scene.Parent$1.doProcessCSS(Parent.java:125)
at javafx.graphics@18.0.1/com.sun.javafx.scene.ParentHelper.processCSSImpl(ParentHelper.java:98)
at javafx.graphics@18.0.1/com.sun.javafx.scene.NodeHelper.processCSS(NodeHelper.java:146)
at javafx.graphics@18.0.1/javafx.scene.Node.processCSS(Node.java:9477)
at javafx.graphics@18.0.1/javafx.scene.Scene.doCSSPass(Scene.java:572)
at javafx.graphics@18.0.1/javafx.scene.Scene.preferredSize(Scene.java:1770)
at javafx.graphics@18.0.1/javafx.scene.Scene$2.preferredSize(Scene.java:396)
at javafx.graphics@18.0.1/com.sun.javafx.scene.SceneHelper.preferredSize(SceneHelper.java:66)
at javafx.graphics@18.0.1/javafx.stage.Window$12.invalidated(Window.java:1163)
at javafx.base@18.0.1/javafx.beans.property.BooleanPropertyBase.markInvalid(BooleanPropertyBase.java:110)
at javafx.base@18.0.1/javafx.beans.property.BooleanPropertyBase.set(BooleanPropertyBase.java:145)
at javafx.graphics@18.0.1/javafx.stage.Window.setShowing(Window.java:1239)
at javafx.graphics@18.0.1/javafx.stage.Window.show(Window.java:1254)
at javafx.graphics@18.0.1/javafx.stage.Stage.show(Stage.java:277)
at com.jfbonline.students.model.controllers.mainUIController.loadAddOrEditWindow(mainUIController.java:246)
at com.jfbonline.students.model.controllers.mainUIController.addDataToDB(mainUIController.java:127)
... 57 more
Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
at java.base/java.util.ImmutableCollections$ListN.indexOf(ImmutableCollections.java:716)
at javafx.base@18.0.1/com.sun.javafx.collections.ObservableListWrapper.indexOf(ObservableListWrapper.java:124)
at javafx.controls@18.0.1/javafx.scene.control.skin.ComboBoxListViewSkin.getIndexOfComboBoxValueInItemsList(ComboBoxListViewSkin.java:478)
at javafx.controls@18.0.1/javafx.scene.control.skin.ComboBoxListViewSkin.updateValue(ComboBoxListViewSkin.java:416)
at javafx.controls@18.0.1/javafx.scene.control.skin.ComboBoxListViewSkin.<init>(ComboBoxListViewSkin.java:169)
at javafx.controls@18.0.1/javafx.scene.control.ComboBox.createDefaultSkin(ComboBox.java:447)
at javafx.controls@18.0.1/javafx.scene.control.Control.doProcessCSS(Control.java:899)
at javafx.controls@18.0.1/javafx.scene.control.Control$1.doProcessCSS(Control.java:89)
at javafx.controls@18.0.1/com.sun.javafx.scene.control.ControlHelper.processCSSImpl(ControlHelper.java:67)
at javafx.graphics@18.0.1/com.sun.javafx.scene.NodeHelper.processCSS(NodeHelper.java:146)
at javafx.graphics@18.0.1/javafx.scene.Node.processCSS(Node.java:9477)
at javafx.graphics@18.0.1/javafx.scene.Node.processCSS(Node.java:9470)
at javafx.graphics@18.0.1/javafx.scene.Node.processCSS(Node.java:9470)
at javafx.graphics@18.0.1/javafx.scene.Scene.doCSSPass(Scene.java:572)
at javafx.graphics@18.0.1/javafx.scene.Scene$ScenePulseListener.pulse(Scene.java:2494)
at javafx.graphics@18.0.1/com.sun.javafx.tk.Toolkit.lambda$runPulse$2(Toolkit.java:405)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at javafx.graphics@18.0.1/com.sun.javafx.tk.Toolkit.runPulse(Toolkit.java:404)
Caused by: java.lang.reflect.InvocationTargetException
at javafx.graphics@18.0.1/com.sun.javafx.tk.Toolkit.firePulse(Toolkit.java:434)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:575)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:555)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.QuantumToolkit.pulseFromQueue(QuantumToolkit.java:548)
at javafx.graphics@18.0.1/com.sun.javafx.tk.quantum.QuantumToolkit.lambda$runToolkit$11(QuantumToolkit.java:352)
at javafx.graphics@18.0.1/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96)
at javafx.graphics@18.0.1/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics@18.0.1/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:184)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: java.lang.NullPointerException
> Task :mainApplication.main() FAILED
Execution failed for task ':mainApplication.main()'.
> Build cancelled while executing task ':mainApplication.main()'
* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.
I tried to reproduce the error using a simpler example but I don't get the error but the example shows what am trying to get too;
package com.example.exampleerror;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.event.EventHandler;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ChoiceBox;
import javafx.scene.image.Image;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.Pane;
import javafx.stage.Modality;
import javafx.stage.Stage;
import java.io.IOException;
import java.util.List;
public class HelloApplication extends Application {
public enum Gender {
M,
F,
O
}
@Override
public void start(Stage stage) throws IOException {
Pane first = new AnchorPane();
Button openSecond = new Button(" Open Second ");
openSecond.setOnMouseClicked(new EventHandler<MouseEvent>() {
@Override
public void handle(MouseEvent event) {
try {
loadAddOrEditWindow();
} catch (IOException e) {
e.printStackTrace();
}
}
});
first.getChildren().add(openSecond);
Scene scene = new Scene(first, 320, 240);
stage.setTitle("Hello!");
stage.setScene(scene);
stage.show();
}
private void loadAddOrEditWindow() throws IOException {
Stage stage = new Stage();
Pane pane = new AnchorPane();
Button save = new Button("Save");
pane.getChildren().add(save);
Scene editScene = new Scene(pane, 320, 240);
ChoiceBox<Gender> genders = new ChoiceBox<>();
genders.setLayoutX(70.0);
genders.setLayoutY(70.0);
genders.setItems(FXCollections.observableList(List.of(Gender.values())));
pane.getChildren().add(genders);
stage.setTitle("Example");
stage.setScene(editScene);
stage.centerOnScreen();
stage.setResizable(false);
stage.initModality(Modality.APPLICATION_MODAL);
stage.show();
}
public static void main(String[] args) {
launch();
}
}
I just want to populate the choicebox using the initialize method each time the button is clicked but an error is occurring.
