Develop Reference

buttons not responding javaFx

The buttons dont give a console output. Two buttons are in a Vbox at the bottom of a BorderPane and should print "new" or "continue" when pressed.
I followed a tutorial and tried to extend it to one more button.
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class Main extends Application implements EventHandler<ActionEvent> {
Button btn1, btn2;
public static void main(String[] args) {
launch(args);
}
public void start(Stage primaryStage) throws Exception {
primaryStage.setTitle("title");
Button btn1 = new Button("new");
Button btn2 = new Button ("continue");
btn1.setOnAction(this);
btn2.setOnAction(this);
VBox vb = new VBox (btn1, btn2);
vb.setSpacing(10);
vb.setPadding(new Insets(20));
BorderPane root = new BorderPane();
root.setBottom(vb);
Scene scene = new Scene (root, 300, 250);
primaryStage.setScene(scene);
primaryStage.show();
}
#Override
public void handle(ActionEvent event) {
if (event.getSource()==btn1) {
System.out.println("new!");
} else if (event.getSource()==btn2) {
System.out.println("continue!");
}
}
}
nothing happens, but there should be a output of "new or continue"

Remove class from buttons.
This way the code will use buttons from fields, instead of creating new ones.
public void start(Stage primaryStage) throws Exception {
primaryStage.setTitle("title");
btn1 = new Button("new");
btn2 = new Button ("continue");
// the rest of the code will be the same
}

error when switching to Java 10

I made a javafx program using a horizontal SplitPane with a Canvas on one side in which something is drawn. When the SplitPane is resized the Canvas resizes with it.
Everything worked fine until I switched to Java 10. Suddenly the Canvas-side can only be expanded, not reduced.
Anyone has an idea why that is?
(The working Java version was 1.8.0_181)
package test;
import javafx.application.Application;
import javafx.geometry.Orientation;
import javafx.scene.Scene;
import javafx.scene.control.SplitPane;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
public class Test extends Application {
private static Display display;
#Override
public void start(Stage primaryStage) {
display = new Display();
StackPane stackPaneDisplay = new StackPane();
stackPaneDisplay.getChildren().add(display);
stackPaneDisplay.setStyle("-fx-background-color: white");
AnchorPane anchorPaneDisplay = new AnchorPane();
anchorPaneDisplay.getChildren().add(stackPaneDisplay);
AnchorPane.setBottomAnchor(stackPaneDisplay, Double.MIN_VALUE);
AnchorPane.setTopAnchor(stackPaneDisplay, Double.MIN_VALUE);
AnchorPane.setLeftAnchor(stackPaneDisplay, Double.MIN_VALUE);
AnchorPane.setRightAnchor(stackPaneDisplay, Double.MIN_VALUE);
display.widthProperty().bind(stackPaneDisplay.widthProperty());
display.heightProperty().bind(stackPaneDisplay.heightProperty());
StackPane stackPaneLeft = new StackPane();
SplitPane splitPane = new SplitPane();
splitPane.setOrientation(Orientation.HORIZONTAL);
splitPane.getItems().addAll(stackPaneLeft, anchorPaneDisplay);
BorderPane root = new BorderPane();
root.setCenter(splitPane);
Scene scene = new Scene(root);
primaryStage.setMaximized(true);
primaryStage.setScene(scene);
primaryStage.show();
splitPane.setDividerPositions(0.2);
}
public static void main(String[] args) {
launch(args);
}
}
and the Canvas-Class
package test;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
public class Display extends Canvas {
GraphicsContext gc = this.getGraphicsContext2D();
public Display() {
widthProperty().addListener(e -> {
draw();
});
}
public void draw() {
gc.strokeOval(500, 500, 100, 100);
}
}
Thanks in advance

javafx graphics without a window

This might be a wierd question but is it possible to draw some sort of graphics without a window using javafx?
To clarify I want to write a circle at the bottom left corner of the screen where everything but the circle is the underlying window. So just removing the titlebar is not really enough

Are you looking for a transparent stage - this puts a red circle on the bottom left of the primary monitor. This might help you in the direction you want to go.
public class TransparentStage extends Application {
#Override
public void start(Stage stage) throws Exception {
stage.initStyle(StageStyle.TRANSPARENT);
Circle c = new Circle(30);
c.setFill(Color.RED);
VBox box = new VBox();
box.getChildren().add(c);
final Scene scene = new Scene(box,300, 250);
scene.setFill(null);
stage.setScene(scene);
stage.setX(20);
stage.setY(Screen.getPrimary().getBounds().getHeight() - 100);
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}

Some sort of transparent window like below
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.layout.VBox;
import javafx.scene.text.Font;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javafx.stage.StageStyle;
public class Main extends Application {
#Override
public void start(Stage stage) {
stage.initStyle(StageStyle.TRANSPARENT);
Text text = new Text("!");
text.setFont(new Font(40));
VBox box = new VBox();
box.getChildren().add(text);
final Scene scene = new Scene(box,300, 250);
scene.setFill(null);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
source : http://www.java2s.com/Code/Java/JavaFX/TRANSPARENTwindow.htm

How to execute multiple stage operations in a single frame with JavaFX?

I would like to execute multiple stage operations in one frame :
stage.sizeToScene()
stage.centerOnScreen()
Currently I can see that the stage is first resized, then centered. I would like both operations to be done atomically on the same re-paint.
Here is a working example :
package sample;
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
public class Main extends Application {
private HBox first = new HBox();
private HBox second = new HBox();
private Button change1 = new Button("Go to 2nd");
private Button change2 = new Button("Go to 1st");
#Override
public void start(Stage primaryStage) throws Exception{
primaryStage.setTitle("Hello World");
first.setSpacing(10);
first.setAlignment(Pos.CENTER_LEFT);
first.getChildren().addAll(
change1, new Label("Hello"), new Label("World")
);
second.setSpacing(10);
second.setAlignment(Pos.CENTER_LEFT);
second.getChildren().addAll(
change2, new Label("BYE MY FRIENDS, THIS IS MUCH LONGER!")
);
change1.setOnAction(event -> {
primaryStage.getScene().setRoot(second);
primaryStage.sizeToScene();
primaryStage.centerOnScreen();
});
change2.setOnAction(event -> {
primaryStage.getScene().setRoot(first);
primaryStage.sizeToScene();
primaryStage.centerOnScreen();
});
primaryStage.setScene(new Scene(first));
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
To reproduce, launch the application, move the window top-left and make it bigger. Then click on the button. You will see that the window is first resized, then moved at the center.
On this example case it's really really fast, because the application is really light. But with a real-world application it's much more noticable.

Why doesn't button add to scene?

package application;
import java.awt.Button;
import javafx.application.Application;
import javafx.stage.Stage;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
public class Main extends Application {
Button button; //Declare Button
public static void main(String[] args) {
launch(args); //calls application
}
#Override
public void start(Stage primaryStage) throws Exception {
//comes from application pack
primaryStage.setTitle("Title Of Window"); //Main Stage
button = new Button (); //Creates Button
button.setLabel("Click Me");
StackPane layout = new StackPane();
layout.getChildren().add(button); //Button in Scene
Scene scene = new Scene (layout, 300, 250); //Sets Scene
primaryStage.setScene(scene); //Stage and Scene
primaryStage.show();
}
Hey guys, so this is first time I am creating something in JavaFX and I was wondering why doesn't my button in Scene add in Layout.GetChildren() line, it keeps on displaying red line underneath add. I am using Eclipse IDE.

you have imported import java.awt.Button, you must import Button class in the javafx package.