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Images showing in scene builder, but not after compilation

I just want to display an image but no matter whati've tried, it's not showing up.
I opened up a new project from a default template to see if I had done something, but it won't work either.
It will show in the scene builder, but once i compile, nothing there.
Main:
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.stage.Stage;
import java.io.IOException;
public class HelloApplication extends Application {
#Override
public void start(Stage stage) throws IOException {
FXMLLoader fxmlLoader = new FXMLLoader(HelloApplication.class.getResource("hello-view.fxml"));
Scene scene = new Scene(fxmlLoader.load(), 400, 600);
stage.setTitle("Hello!");
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch();
}
}
and the fxml file being:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.AnchorPane?>
<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/16" xmlns:fx="http://javafx.com/fxml/1">
<children>
<ImageView fitHeight="325.0" fitWidth="347.0" layoutX="138.0" layoutY="38.0" pickOnBounds="true" preserveRatio="true">
<image>
<Image url="#../../../Images/471962_nemuli_catstronaut.png" />
</image>
</ImageView>
</children>
</AnchorPane>
Any clue what's happening? I am running on linux if that means anything.
file tree

Why can't I add XY point to line chart in new window

I'm using JavaFX, problem is when traing drawing new line in XYChart, I get error NullPointerException. Its hapen after create a new Pane. Secont Pane is opening with line chart but is empty. I get the error from this line of the below code.
lineChart.getData().addAll(series);
When I trying to do this in primary window everything is going fine and the line is drawing correctly. But when i trying to do this after i create a second pane i get a error NullPointerException.
Fragment of code sending me a error:
chartsButton.setOnAction(new EventHandler<ActionEvent>() {
#SuppressWarnings("unchecked")
#Override
public void handle(ActionEvent event) {
Parent chartParent;
try {
Stage chartsWindow = new Stage();
chartParent = FXMLLoader.load(getClass().getResource("/eng/gascalculator/view/ChartsPane.fxml"));
chartsWindow.setTitle("Charts");
chartsWindow.setScene(new Scene(chartParent, 450, 450));
chartsWindow.show();
} catch (IOException e) {
}
XYChart.Series<String, Number> series = new XYChart.Series<String, Number>();
series.getData().add(new XYChart.Data<String, Number>("Jan", 10));
series.getData().add(new XYChart.Data<String, Number>("Feb", 30));
lineChart.getData().addAll(series);
}
});
Its should works like, when i click a chart Button, new pane should open with chart line and data on the chart.
I think this will be a problem with a new separate instance, like #Slaw tell. Below I prepare new program with minimal code. I have 2 fxml file both have controlled assassin to MainController class. MainPane open correct but when I push button to open second Pane with chart i get information the lineChart is null.
MainConntroller class:
package application;
import java.io.IOException;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.fxml.Initializable;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.XYChart;
import javafx.scene.control.Button;
import javafx.stage.Stage;
public class MainController implements Initializable {
#FXML
private Button chartButton;
#FXML
private LineChart<String, Number> lineChart;
#Override
public void initialize(URL location, ResourceBundle resources) {
chartButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
Parent chartParent;
try {
Stage chartsWindow = new Stage();
chartParent = FXMLLoader.load(getClass().getResource("/application/ChartPane.fxml"));
chartsWindow.setTitle("Charts");
chartsWindow.setScene(new Scene(chartParent, 450, 450));
chartsWindow.show();
} catch (IOException e) {
}
XYChart.Series<String, Number> series = new XYChart.Series<String, Number>();
series.getData().add(new XYChart.Data<String, Number>("Jan", 10));
series.getData().add(new XYChart.Data<String, Number>("Feb", 30));
lineChart.getData().addAll(series);
}
});
}
}
Main class:
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 stage) throws Exception {
Parent parent = FXMLLoader.load(getClass().getResource("/application/MainPane.fxml"));
Scene scene = new Scene(parent);
stage.setScene(scene);
stage.setTitle("First window");
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
MainPane.fxml file:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.layout.AnchorPane?>
<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity"
minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0"
xmlns="http://javafx.com/javafx/10.0.1"
xmlns:fx="http://javafx.com/fxml/1" fx:controller="application.MainController">
<children>
<Button fx:id="chartButton" layoutX="265.0" layoutY="188.0"
mnemonicParsing="false" text="Chart" />
</children>
ChartPane.fxml file:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.chart.CategoryAxis?>
<?import javafx.scene.chart.LineChart?>
<?import javafx.scene.chart.NumberAxis?>
<?import javafx.scene.layout.AnchorPane?>
<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity"
minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0"
xmlns="http://javafx.com/javafx/10.0.1"
xmlns:fx="http://javafx.com/fxml/1" fx:controller="application.MainController">
<children>
<LineChart fx:id="lineChart" layoutX="50.0">
<xAxis>
<CategoryAxis side="BOTTOM" />
</xAxis>
<yAxis>
<NumberAxis side="LEFT" />
</yAxis>
</LineChart>
</children>
</AnchorPane>

Loading new resource in same window

I am currently migrating all my .form files over to .fxml and I'm having a bit trouble loading another page within the same window.
With .form method I was able to establish a card layout and switch it within that.
What I would do is create a card layout and have the forms load in there.
I created a few test .fxml and some basic code. It loads the second one but in a new window and I'm trying to avoid that and load it within the same window.
index.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="480.0" prefWidth="320.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="Test">
<children>
<Button id="btnbuy" fx:id="btnbuy" layoutX="134.0" layoutY="2.0" mnemonicParsing="false" onAction="#loadSecondFxml" text="Purchase" />
<Button id="btnSell" fx:id="btnsell" layoutX="140.0" layoutY="454.0" mnemonicParsing="false" text="Sell" />
</children>
</AnchorPane>
MainPage.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="480.0" prefWidth="320.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="Test">
<children>
<Pane layoutX="6.0" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="480.0" prefWidth="320.0">
<children>
<Label layoutX="146.0" layoutY="232.0" text="You got here" />
</children></Pane>
</children>
</AnchorPane>
Test.java
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.stage.Stage;
public class Test extends Application {
private MainPage parentForm;
//private Panel panel;
public Button btnbuy;
public Button btnsell;
public Test(){
}
public void start(Stage primaryStage) throws Exception{
Parent root = FXMLLoader.load(getClass().getResource("Index.fxml"));
primaryStage.setTitle("Hello World");
primaryStage.setScene(new Scene(root, 320, 480));
primaryStage.show();
}
public void loadSecondFxml() throws Exception{
Stage primaryStage = new Stage();
Parent root = FXMLLoader.load(getClass().getResource("MainPage.fxml"));
primaryStage.setTitle("Hi");
primaryStage.setScene(new Scene(root, 320, 480));
primaryStage.show();
}
public static void main(String args[]){
launch(args);
}
}
I know it has something to do with the setscene portion. But I'm having trouble trying to get the syntax right.

There are multiple ways of doing this. Which one works best for you depends on your needs:
Replacing the root
By replacing the root you can replace all the contents shown in a window.
#Override
public void start(Stage primaryStage) {
final Region r1 = new Region();
r1.setStyle("-fx-background-color: yellow;");
final Region r2 = new Region();
r2.setStyle("-fx-background-color: blue;");
final Scene scene = new Scene(r1);
scene.setOnMouseClicked(evt -> {
scene.setRoot(scene.getRoot() == r1 ? r2 : r1); // swap roots
});
primaryStage.setScene(scene);
primaryStage.show();
}
Modifying part of the scene
By modifying a parent in the scene you can change the display.
BorderPane
This layout allows you to easily replace it's (up to) 5 nodes:
#Override
public void start(Stage primaryStage) {
final Region r1 = new Region();
r1.setStyle("-fx-background-color: yellow;");
final Region r2 = new Region();
r2.setStyle("-fx-background-color: blue;");
final BorderPane root = new BorderPane(r1);
Button btn = new Button("swap");
btn.setOnAction(evt -> {
root.setCenter(root.getCenter() == r1 ? r2 : r1);
});
root.setTop(btn);
final Scene scene = new Scene(root, 400, 400);
primaryStage.setScene(scene);
primaryStage.show();
}
Modifying the child list of some other layout
This can be a bit more complex than using BorderPane, but Panes and Group allow you to modify the children list to modify the layout:
#Override
public void start(Stage primaryStage) {
final Region r1 = new Region();
r1.setStyle("-fx-background-color: yellow;");
VBox.setVgrow(r1, Priority.ALWAYS);
final Region r2 = new Region();
r2.setStyle("-fx-background-color: blue;");
VBox.setVgrow(r2, Priority.ALWAYS);
final VBox root = new VBox();
Button btn = new Button("swap");
btn.setOnAction(evt -> {
root.getChildren().set(1, root.getChildren().get(1) == r1 ? r2 : r1);
});
root.getChildren().addAll(btn, r1);
final Scene scene = new Scene(root, 400, 400);
primaryStage.setScene(scene);
primaryStage.show();
}
Something like TabPane may also suit your needs.
Using something like this with fxmls requires you to provide access to the object managing the replacement. You can read about this topic here: Passing Parameters JavaFX FXML
You shouldn't use the Application class as controller class though. This violates the single responsibility principle. Also you create a new instance of the class every time a fxml with the class specified as value of the fx:controller attribute is loaded. The Application class is supposed to be the "entry point" of your program.

Trouble applying CSS to programatically created Pane on MouseEvent

I have a stack pane that when the mouse enters, I create a pane, stick some text in it, and display it near the mouse.
StatisticsController.java
stackPane.setOnMouseEntered(event -> {
Pane pane = new Pane();
Text text = new Text("Example Text");
//Add the text to the pane and set it near the mouse
pane.getChildren().add(text);
pane.setLayoutY(event.getSceneY() - 50);
pane.setLayoutX(event.getSceneX() - 100);
//add the style class to give it a blueBG background
pane.getStyleClass().add("blueBG");
// add it too our root
getRoot().getChildren().add(pane);
});
As you can see below when the Pane and text appear when I roll over the stackPane (the black circle and question mark in the image).
However it doesn't have the blue background I'm looking for.
What I find strange is if instead of adding it to the root and I add it to an existing Vbox, it styles correctly (Here I roll over the same stackPane):
So:
//Styles Correctly
getInfoBox().getChildren().add(pane);
// Adds but does not style
getRoot().getChildren().add(pane);
Some things that may be worth noting:
1)getInfoBox() is a static getter. I have multiple controllers which extend a MasterController which has static instance variables to things all controllers would want to be able to access - like the infoBox, to display information.
2)The root is a BorderPane made in the Main class:
Main.java
//Create the root
BorderPane root = new BorderPane();
// I've cut it out to save space but this repeats 4 times to set
//an .fxml file for the top, left, right and bottom of the borderPane ///
FXMLLoader headerLoader = new FXMLLoader(getClass().getResource("/view/header.fxml"));
Parent headerRoot = headerLoader.load();
root.setTop(headerRoot);
//------------------------------------------//
//Set the static reference in the MasterController
MasterController.setRoot(root);
Scene scene = new Scene(root,1366,768);
primaryStage.setScene(scene);
primaryStage.show();
3) The css files are all declared in the .fxml files using Scene Builder. The top, bottom, left, right .fxml files all have the same css (main.css). So does the statistic.fxml which is loaded on button click into the center (you can see in the image)
Suggestion: Could it be because the CSS is not defined for the Scene or BorderPane itself, it only applies to nodes added into the borderPane sections? If so how would I go about letting the enter Scene/Stage use the same css and would that negate adding in the css to each .fxml?
Edit:
When adding this code to the main to apply the CSS to the scene:
Scene scene = new Scene(root,1366,768);
scene.getStylesheets().add(getClass().getResource("/css/main.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.show();
I get this:
So the CSS for the text is now working, but not for the Pane? I have no idea why this might happen.
// ---- REPRODUCTION -- //
Main.java
package sample;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
public class Main extends Application {
#Override
public void start(Stage primaryStage) throws Exception{
BorderPane bp = new BorderPane();
MasterController.setRoot(bp);
Parent left = FXMLLoader.load(getClass().getResource("left.fxml"));
Parent right = FXMLLoader.load(getClass().getResource("right.fxml"));
bp.setLeft(left);
bp.setRight(right);
Scene scene = new Scene(bp, 600, 400);
scene.getStylesheets().add(getClass().getResource("main.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
MasterController.java
package sample;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.VBox;
public class MasterController {
private static VBox rightBox;
private static BorderPane root;
public static VBox getRightBox() {
return rightBox;
}
public static void setRightBox(VBox rightBox) {
MasterController.rightBox = rightBox;
}
public static BorderPane getRoot() {
return root;
}
public static void setRoot(BorderPane root) {
MasterController.root = root;
}
}
LeftController.java
package sample;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import java.io.IOException;
public class LeftController extends MasterController {
#FXML
public void loadCenter(ActionEvent event) {
try {
FXMLLoader loader = new FXMLLoader(getClass().getResource("center.fxml"));
Parent center = loader.load();
getRoot().setCenter(center);
} catch (IOException e){
e.printStackTrace();
}
}
}
CenterController.java
package sample;
import javafx.application.Platform;
import javafx.fxml.FXML;
import javafx.scene.layout.Pane;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.text.Text;
public class CenterController extends MasterController {
#FXML
private VBox center;
public void initialize() {
Platform.runLater(this::build);
}
public void build() {
center.getChildren().add(new Text("loaded"));
StackPane stackPane = new StackPane();
Text text = new Text("ROLL OVER");
stackPane.getChildren().add(text);
center.getChildren().add(stackPane);
stackPane.setOnMouseEntered(event -> {
getRightBox().getChildren().clear();
Pane pane1 = new Pane();
Text exampleText1 = new Text("Example Text");
pane1.getStyleClass().add("blueBG");
Pane pane2 = new Pane();
Text exampleText2 = new Text("Example Text");
pane2.getStyleClass().add("blueBG");
pane1.getChildren().add(exampleText1);
pane2.getChildren().add(exampleText2);
pane1.setLayoutY(event.getSceneY() + 40);
pane1.setLayoutX(event.getSceneX() - 40);
getRoot().getChildren().add(pane1);
getRightBox().getChildren().add(pane2);
});
}
}
RightController.java
package sample;
import javafx.application.Platform;
import javafx.fxml.FXML;
import javafx.scene.layout.VBox;
public class RightController extends MasterController {
#FXML
private VBox rightBox;
public void initialize() {
setRightBox(rightBox);
}
}
left.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<VBox maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="200.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.LeftController">
<children>
<Button mnemonicParsing="false" onAction="#loadCenter" prefHeight="38.0" prefWidth="200.0" text="Click me to load center" />
</children>
</VBox>
center.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.text.*?>
<?import javafx.scene.layout.*?>
<VBox fx:id="center" alignment="TOP_CENTER" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="200.0" stylesheets="#main.css" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.CenterController">
<children>
<Text strokeType="OUTSIDE" strokeWidth="0.0" text="Center" />
</children>
</VBox>
right.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.text.*?>
<?import javafx.scene.layout.*?>
<VBox fx:id="rightBox" alignment="TOP_CENTER" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="200.0" stylesheets="#main.css" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.RightController">
<children>
<Text strokeType="OUTSIDE" strokeWidth="0.0" text="Right Box" />
</children>
</VBox>
main.css
.blueBG {
-fx-background-color: aqua;
}
You should get the following result. You can see the pane is being styled correctly when added to the right, but not when added too the root.

BorderPane only applies layout to the center, left, right, top and bottom children. It's however the parent of a layout (or the scene in case of a root) that sets the size of a Region during a layout pass (or not, like in this case).
The result is that the style is applied to the Pane, but the size of the Pane remains 0. You can verify this by adding
pane1.resize(100, 100);
to the event handler to set the size of the pane.
You need to use a different kind of layout as parent for pane1's size to become non-empty or resize it yourself.

How do you add nodes to an object that is not the main parent (javafx)?

I could not find anything on the topic anywhere i looked. I would like to add a rectangle to my AnchorPane (anchorPaneOne) that is inside my ScrollPane (scrollPane) but whatever i see to do i keep getting errors.
Here is my code:
Main Class:
package application;
import javafx.application.Application;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.ScrollPane;
import javafx.scene.layout.AnchorPane;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
public class Main extends Application {
#FXML
ScrollPane scrollPane;
#FXML
AnchorPane main;
#FXML
AnchorPane anchorPaneOne;
public void start(Stage primaryStage) {
try {
Parent root = FXMLLoader.load(getClass().getResource("/fxml/Main.fxml"));
Scene scene = new Scene(root,600,400);
primaryStage.setScene(scene);
primaryStage.setTitle("Stack Overflow Example");
primaryStage.show();
Rectangle r = new Rectangle();
//It will not let me do anchorPaneOne.getChildren().add(r);
} catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
launch(args);
}
}
Main.fxml:
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.*?>
<?import java.lang.*?>
<?import javafx.scene.layout.*?>
<AnchorPane fx:id="main" 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">
<children>
<ScrollPane fx:id="scrollPane" prefHeight="400.0" prefWidth="600.0">
<content>
<AnchorPane fx:id="anchorPaneOne" minHeight="0.0" minWidth="0.0" prefHeight="800.0" prefWidth="585.0" />
</content>
</ScrollPane>
</children>
</AnchorPane>
Any assistance would be appreciated.
Thanks

The loader needs to know where to inject the instances to - without the field anchorPaneOne can't be instantiated and remains null. That's done by the controller property which must be set before actually loading the ui:
// create a loader
FXMLLoader loader = new FXMLLoader(getClass().getResource(resource));
// set this instance as its controller
loader.setController(this);
// load the ui
Parent root = loader.load();
Scene scene = new Scene(root, 600, 400);
primaryStage.setScene(scene);
primaryStage.setTitle("Stack Overflow Example");
primaryStage.show();
Rectangle r = new Rectangle(100, 100);
// now the field is instantiated and can be accessed without NPE
anchorPaneOne.getChildren().add(r);