I have done it under neatbeans IDE and just added ToggleGroup for grouping radion buttons inorder to select one at time. package tempconverter; import javafx.application.Application; import javafx.beans.value.ChangeListener; import javafx.beans.value.ObservableValue; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.geometry.Pos; import javafx.scene.Scene; import javafx.scene.control.Button; import javafx.scene.control.Label; import javafx.scene.control.RadioButton; import javafx.scene.control.ScrollPane; import javafx.scene.control.TextArea; import javafx.scene.control.TextField; import javafx.scene.control.Toggle; import javafx.scene.control.ToggleGroup; import javafx.scene.layout.BorderPane; import javafx.scene.layout.StackPane; import javafx.scene.layout.VBox; import javafx.stage.Stage; public class Tempconverter extends Application { /** * @param args the command line arguments executes project */ final ToggleGroup group1 = new ToggleGroup(); final ToggleGroup group2 = new ToggleGroup(); public static void main(String[] args) { launch(args); } @Override public void start(Stage primaryStage) throws Exception { BorderPane pane = new BorderPane(); //the big picture BorderPane p1 = new BorderPane();//top BorderPane p2 = new BorderPane(); //bottom Label temp = new Label(\"Enter a temperature\"); //enter temp label Label convertTemp = new Label(\"Converted temperature\"); //converted temp label Label input = new Label(\"Input Scale\");//input scale label Label output = new Label(\"Output Scale\");//Output Scale label TextField tempText = new TextField(); //text field to enter temp TextField convertText = new TextField(); //output textfield for the converted temp VBox scaleIn = new VBox(15); VBox scaleOut = new VBox(15); RadioButton c = new RadioButton(\"celcius\"); //button for celcius on input side c.setToggleGroup(group1); RadioButton f = new RadioButton(\"Fahrenheit\");//button for Fahrenheit on input side f.setToggleGroup(group1); RadioButton k = new RadioButton(\"kelvin\");//button for kelvin on inputside k.setToggleGroup(group1); RadioButton c1 = new RadioButton(\"celcius\");//button for celcius on outputside c1.setToggleGroup(group2); RadioButton f1 = new RadioButton(\"Fahrenheit\"); //button for f on output side f1.setToggleGroup(group2); RadioButton k1 = new RadioButton(\"kelvin\"); //button for kelvin on output side k1.setToggleGroup(group2); p1.setStyle(\"-fx-border-color:red\"); //set top border pane to red p1.setRight(tempText); p1.setLeft(temp); pane.setTop(p1); pane.setBottom(p2); p2.setLeft(convertTemp); p2.setRight(convertText); p2.setStyle(\"-fx-border-color:red\"); input.setPrefWidth(100); output.setPrefWidth(100); c.setPrefWidth(100); f.setPrefWidth(100); k.setPrefWidth(100); c1.setPrefWidth(100); f1.setPrefWidth(100); k1.setPrefWidth(100); scaleIn.setStyle(\"-fx-border-color:red\"); scaleIn.getChildren().addAll(input, c, f, k); scaleIn.setAlignment(Pos.CENTER); pane.setLeft(scaleIn); TextArea.

1. I have done it under neatbeans IDE and just added ToggleGroup for grouping radion buttons
inorder to select one at time.
package tempconverter;
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.RadioButton;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.TextArea;
import javafx.scene.control.TextField;
import javafx.scene.control.Toggle;
import javafx.scene.control.ToggleGroup;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class Tempconverter extends Application {
/**
* @param args the command line arguments executes project
*/
final ToggleGroup group1 = new ToggleGroup();
final ToggleGroup group2 = new ToggleGroup();
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage primaryStage) throws Exception {
BorderPane pane = new BorderPane(); //the big picture
BorderPane p1 = new BorderPane();//top

2. BorderPane p2 = new BorderPane(); //bottom
Label temp = new Label("Enter a temperature"); //enter temp label
Label convertTemp = new Label("Converted temperature"); //converted temp label
Label input = new Label("Input Scale");//input scale label
Label output = new Label("Output Scale");//Output Scale label
TextField tempText = new TextField(); //text field to enter temp
TextField convertText = new TextField(); //output textfield for the converted temp
VBox scaleIn = new VBox(15);
VBox scaleOut = new VBox(15);
RadioButton c = new RadioButton("celcius"); //button for celcius on input side
c.setToggleGroup(group1);
RadioButton f = new RadioButton("Fahrenheit");//button for Fahrenheit on input side
f.setToggleGroup(group1);
RadioButton k = new RadioButton("kelvin");//button for kelvin on inputside
k.setToggleGroup(group1);
RadioButton c1 = new RadioButton("celcius");//button for celcius on outputside
c1.setToggleGroup(group2);
RadioButton f1 = new RadioButton("Fahrenheit"); //button for f on output side
f1.setToggleGroup(group2);
RadioButton k1 = new RadioButton("kelvin"); //button for kelvin on output side
k1.setToggleGroup(group2);
p1.setStyle("-fx-border-color:red"); //set top border pane to red
p1.setRight(tempText);
p1.setLeft(temp);
pane.setTop(p1);
pane.setBottom(p2);
p2.setLeft(convertTemp);
p2.setRight(convertText);
p2.setStyle("-fx-border-color:red");
input.setPrefWidth(100);
output.setPrefWidth(100);
c.setPrefWidth(100);
f.setPrefWidth(100);
k.setPrefWidth(100);

3. c1.setPrefWidth(100);
f1.setPrefWidth(100);
k1.setPrefWidth(100);
scaleIn.setStyle("-fx-border-color:red");
scaleIn.getChildren().addAll(input, c, f, k);
scaleIn.setAlignment(Pos.CENTER);
pane.setLeft(scaleIn);
TextArea error = new TextArea();
error.setEditable(false);//makes the error message unable to edit
convertText.setEditable(false);//makes output unable to edit
ScrollPane p3 = new ScrollPane(error);
p3.setStyle("-fx-border-color:red");
pane.setCenter(p3);
scaleOut.setStyle("-fx-border-color:red");
scaleOut.getChildren().addAll(output, c1, f1, k1);
scaleOut.setAlignment(Pos.CENTER);
pane.setRight(scaleOut);
//makes it so the input can only be digits.
/*tempText.setOnAction(new EventHandler() {
@Override
public void handle(ActionEvent e) {
// force the field to be numeric only
tempText.textProperty().addListener(new ChangeListener() {
@Override
public void changed(ObservableValue observable, String oldValue, String newValue) {
if (!newValue.matches("d*")) {
tempText.setText(newValue.replaceAll("[^d]", ""));
}
}
});
{
}
}
});
*/
group1.selectedToggleProperty().addListener(new ChangeListener(){

4. public void changed(ObservableValue ov,
Toggle old_toggle, Toggle new_toggle) {
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == c1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = data * 1.8 + 32;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = data + 275.15;
convertText.setText(Double.toString(result));
}
// f to other
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == f1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = (data * 459.67) * 5/9;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = (data - 32) * 5/9;
convertText.setText(Double.toString(result));
}
//k to other
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == k1){
String data= tempText.getText();
convertText.setText(data);
}

5. if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = (data * (9/5)) - 459.67;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = data -273.15;
convertText.setText(Double.toString(result));
}
}
});
group2.selectedToggleProperty().addListener(new ChangeListener(){
public void changed(ObservableValue ov,
Toggle old_toggle, Toggle new_toggle) {
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == c1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = data * 1.8 + 32;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = data + 275.15;
convertText.setText(Double.toString(result));
}
//f to other
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == f1){
String data= tempText.getText();
convertText.setText(data);
}

6. if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = (data * 459.67) * 5/9;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = (data - 32) * 5/9;
convertText.setText(Double.toString(result));
}
//k to other
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == k1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = (data * (9/5)) - 459.67;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = data -273.15;
convertText.setText(Double.toString(result));
}
}
});
convertText.setOnAction(e -> {
//code for the output hander
});
//event handlers for the radio buttons
c.setOnAction(e -> {
if (c.isSelected()) {

7. //need code in here
}
});
f.setOnAction(e -> {
if (f.isSelected()) {
//need code in here
}
});
k.setOnAction(e -> {
if (k.isSelected()) {
//need code in here
}
});
//set action handler for the radio buttons
c1.setOnAction(e -> {
if (c1.isSelected()) {
//need code in here
}
});
f1.setOnAction(e -> {
if (f1.isSelected()) {
//need code in here
}
});
k1.setOnAction(e -> {
if (k1.isSelected()) {
//need code in here
}
});
Scene scene = new Scene(pane, 400, 200);
primaryStage.setTitle("Temp Conversion");
primaryStage.setScene(scene);
primaryStage.show();
}
}

8. Solution
I have done it under neatbeans IDE and just added ToggleGroup for grouping radion buttons
inorder to select one at time.
package tempconverter;
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.RadioButton;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.TextArea;
import javafx.scene.control.TextField;
import javafx.scene.control.Toggle;
import javafx.scene.control.ToggleGroup;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class Tempconverter extends Application {
/**
* @param args the command line arguments executes project
*/
final ToggleGroup group1 = new ToggleGroup();
final ToggleGroup group2 = new ToggleGroup();
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage primaryStage) throws Exception {
BorderPane pane = new BorderPane(); //the big picture

9. BorderPane p1 = new BorderPane();//top
BorderPane p2 = new BorderPane(); //bottom
Label temp = new Label("Enter a temperature"); //enter temp label
Label convertTemp = new Label("Converted temperature"); //converted temp label
Label input = new Label("Input Scale");//input scale label
Label output = new Label("Output Scale");//Output Scale label
TextField tempText = new TextField(); //text field to enter temp
TextField convertText = new TextField(); //output textfield for the converted temp
VBox scaleIn = new VBox(15);
VBox scaleOut = new VBox(15);
RadioButton c = new RadioButton("celcius"); //button for celcius on input side
c.setToggleGroup(group1);
RadioButton f = new RadioButton("Fahrenheit");//button for Fahrenheit on input side
f.setToggleGroup(group1);
RadioButton k = new RadioButton("kelvin");//button for kelvin on inputside
k.setToggleGroup(group1);
RadioButton c1 = new RadioButton("celcius");//button for celcius on outputside
c1.setToggleGroup(group2);
RadioButton f1 = new RadioButton("Fahrenheit"); //button for f on output side
f1.setToggleGroup(group2);
RadioButton k1 = new RadioButton("kelvin"); //button for kelvin on output side
k1.setToggleGroup(group2);
p1.setStyle("-fx-border-color:red"); //set top border pane to red
p1.setRight(tempText);
p1.setLeft(temp);
pane.setTop(p1);
pane.setBottom(p2);
p2.setLeft(convertTemp);
p2.setRight(convertText);
p2.setStyle("-fx-border-color:red");
input.setPrefWidth(100);
output.setPrefWidth(100);
c.setPrefWidth(100);
f.setPrefWidth(100);

10. k.setPrefWidth(100);
c1.setPrefWidth(100);
f1.setPrefWidth(100);
k1.setPrefWidth(100);
scaleIn.setStyle("-fx-border-color:red");
scaleIn.getChildren().addAll(input, c, f, k);
scaleIn.setAlignment(Pos.CENTER);
pane.setLeft(scaleIn);
TextArea error = new TextArea();
error.setEditable(false);//makes the error message unable to edit
convertText.setEditable(false);//makes output unable to edit
ScrollPane p3 = new ScrollPane(error);
p3.setStyle("-fx-border-color:red");
pane.setCenter(p3);
scaleOut.setStyle("-fx-border-color:red");
scaleOut.getChildren().addAll(output, c1, f1, k1);
scaleOut.setAlignment(Pos.CENTER);
pane.setRight(scaleOut);
//makes it so the input can only be digits.
/*tempText.setOnAction(new EventHandler() {
@Override
public void handle(ActionEvent e) {
// force the field to be numeric only
tempText.textProperty().addListener(new ChangeListener() {
@Override
public void changed(ObservableValue observable, String oldValue, String newValue) {
if (!newValue.matches("d*")) {
tempText.setText(newValue.replaceAll("[^d]", ""));
}
}
});
{
}
}
});
*/

11. group1.selectedToggleProperty().addListener(new ChangeListener(){
public void changed(ObservableValue ov,
Toggle old_toggle, Toggle new_toggle) {
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == c1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = data * 1.8 + 32;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = data + 275.15;
convertText.setText(Double.toString(result));
}
// f to other
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == f1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = (data * 459.67) * 5/9;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = (data - 32) * 5/9;
convertText.setText(Double.toString(result));
}
//k to other
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == k1){
String data= tempText.getText();
convertText.setText(data);

12. }
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = (data * (9/5)) - 459.67;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = data -273.15;
convertText.setText(Double.toString(result));
}
}
});
group2.selectedToggleProperty().addListener(new ChangeListener(){
public void changed(ObservableValue ov,
Toggle old_toggle, Toggle new_toggle) {
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == c1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = data * 1.8 + 32;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == c && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = data + 275.15;
convertText.setText(Double.toString(result));
}
//f to other
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == f1){
String data= tempText.getText();
convertText.setText(data);

13. }
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == k1){
double data = Double.parseDouble(tempText.getText());
double result = (data * 459.67) * 5/9;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == f && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = (data - 32) * 5/9;
convertText.setText(Double.toString(result));
}
//k to other
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == k1){
String data= tempText.getText();
convertText.setText(data);
}
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == f1){
double data = Double.parseDouble(tempText.getText());
double result = (data * (9/5)) - 459.67;
convertText.setText(Double.toString(result));
}
if(group1.getSelectedToggle() == k && group2.getSelectedToggle() == c1){
double data = Double.parseDouble(tempText.getText());
double result = data -273.15;
convertText.setText(Double.toString(result));
}
}
});
convertText.setOnAction(e -> {
//code for the output hander
});
//event handlers for the radio buttons
c.setOnAction(e -> {

14. if (c.isSelected()) {
//need code in here
}
});
f.setOnAction(e -> {
if (f.isSelected()) {
//need code in here
}
});
k.setOnAction(e -> {
if (k.isSelected()) {
//need code in here
}
});
//set action handler for the radio buttons
c1.setOnAction(e -> {
if (c1.isSelected()) {
//need code in here
}
});
f1.setOnAction(e -> {
if (f1.isSelected()) {
//need code in here
}
});
k1.setOnAction(e -> {
if (k1.isSelected()) {
//need code in here
}
});
Scene scene = new Scene(pane, 400, 200);
primaryStage.setTitle("Temp Conversion");
primaryStage.setScene(scene);
primaryStage.show();
}
}