JavaFX | RadioButton with examples

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RadioButtons are a part of JavaFx package. RadioButtons are mainly used to create a series of items where only one can be selected. When a Radio button is pressed and released an Action event is sent, this Action Event can be handled using an Event Handler.
RadioButton can be added to Toggle Group so that the user cannot select more than one item . By default a radio button is not a part of any toggle group. The selected item of a toggle group can be found using getSelectedToggle() function.

Constructors of the RadioButton class:

RadioButton():Creates a radio button with an empty string for its label.
RadioButton(String t):Creates a radio button with the specified text as its label

Commonly used methods:

method	explanation
getText()	returns the textLabel for radio button
isSelected()	returns whether the radiobutton is selected or not
setSelected(boolean b)	sets whether the radiobutton is selected or not
setToggleGroup(ToggleGroup tg)	sets the toggle group for the radio button
fire()	Toggles the state of the radio button if and only if the RadioButton has not already selected or is not part of a ToggleGroup.

Below programs illustrate the RadioButton class:

Program to create RadioButton and add it to the stage: This program creates a RadioButton indicated by the name r1, r2, r3. The radio button will be created inside a scene, which in turn will be hosted inside a stage (which is the top level JavaFX container). The function setTitle() is used to provide title to the stage. Then a tile-pane is created, on which addChildren() method is called to attach the radio button inside the scene, along with the resolution specified by (200, 200) in the code. Finally, the show() method is called to display the final results.

// Java program to create RadioButton and add it to the stage
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.collections.*;
import javafx.stage.Stage;
import javafx.scene.text.Text.*;
import javafx.scene.text.*;
public class radiobutton extends Application {
  
    // launch the application
    public void start(Stage s)
    {
        // set title for the stage
        s.setTitle("creating RadioButton");
  
        // create a tile pane
        TilePane r = new TilePane();
  
        // create a label
        Label l = new Label("This is a Radiobutton example ");
  
        // create radiobuttons
        RadioButton r1 = new RadioButton("male");
        RadioButton r2 = new RadioButton("female");
        RadioButton r3 = new RadioButton("others");
  
        // add label
        r.getChildren().add(l);
        r.getChildren().add(r1);
        r.getChildren().add(r2);
        r.getChildren().add(r3);
  
        // create a scene
        Scene sc = new Scene(r, 200, 200);
  
        // set the scene
        s.setScene(sc);
  
        s.show();
    }
  
    public static void main(String args[])
    {
        // launch the application
        launch(args);
    }
}

Output:

Program to create RadioButton and add it to a ToggleGroup: This program creates a RadioButton indicated by the name r1, r2, r3. The radio button will be created inside a scene, which in turn will be hosted inside a stage (which is the top level JavaFX container). The function setTitle() is used to provide title to the stage. A toggle group is created and the radio buttons are added to the toggle group using setToggleGroup() function. Then a tile-pane is created, on which addChildren() method is called to attach the radio button inside the scene, along with the resolution specified by (200, 200) in the code. Finally, the show() method is called to display the final results.

// Java Program to create RadioButton and add it to a ToggleGroup
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.collections.*;
import javafx.stage.Stage;
import javafx.scene.text.Text.*;
import javafx.scene.text.*;
public class radiobutton_1 extends Application {
    // labels
    Label l;
  
    // launch the application
    public void start(Stage s)
    {
        // set title for the stage
        s.setTitle("creating RadioButton");
  
        // create a tile pane
        TilePane r = new TilePane();
  
        // create a label
        l = new Label("This is a Radiobutton example ");
  
        // create a toggle group
        ToggleGroup tg = new ToggleGroup();
  
        // create radiobuttons
        RadioButton r1 = new RadioButton("male");
        RadioButton r2 = new RadioButton("female");
        RadioButton r3 = new RadioButton("others");
  
        // add radiobuttons to toggle group
        r1.setToggleGroup(tg);
        r2.setToggleGroup(tg);
        r3.setToggleGroup(tg);
  
        // add label
        r.getChildren().add(l);
        r.getChildren().add(r1);
        r.getChildren().add(r2);
        r.getChildren().add(r3);
  
        // create a scene
        Scene sc = new Scene(r, 200, 200);
  
        // set the scene
        s.setScene(sc);
  
        s.show();
    }
  
    public static void main(String args[])
    {
        // launch the application
        launch(args);
    }
}

Output:

Program to create RadioButton, add it to a ToggleGroup and add a listener to it: This program creates a RadioButton indicated by the name r1, r2, r3. The radio button will be created inside a scene, which in turn will be hosted inside a stage (which is the top level JavaFX container). The function setTitle() is used to provide title to the stage. A toggle group is created and the radio buttons are added to the toggle group using setToggleGroup() function. A label l2 is created to show which radio button is selected. A change listener is added to handle any change in the selection of the radio buttons (using the addListener() function). The change in selection is depicted by changing the text of label l2. Then a tile-pane is created, on which addChildren() method is called to attach the radio button inside the scene, along with the resolution specified by (200, 200) in the code. Finally, the show() method is called to display the final results.

// Java Program to create RadioButton, add it to a ToggleGroup and add a listener to it
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.event.ActionEvent;
import javafx.event.*;
import javafx.collections.*;
import javafx.stage.Stage;
import javafx.scene.text.Text.*;
import javafx.scene.text.*;
import javafx.beans.value.*;
public class radiobutton_2 extends Application {
  
    // launch the application
    public void start(Stage s)
    {
        // set title for the stage
        s.setTitle("creating RadioButton");
  
        // create a tile pane
        TilePane r = new TilePane();
  
        // create a label
        Label l = new Label("This is a Radiobutton example ");
        Label l2 = new Label("nothing selected");
  
        // create a toggle group
        ToggleGroup tg = new ToggleGroup();
  
        // create radiobuttons
        RadioButton r1 = new RadioButton("male");
        RadioButton r2 = new RadioButton("female");
        RadioButton r3 = new RadioButton("others");
  
        // add radiobuttons to toggle group
        r1.setToggleGroup(tg);
        r2.setToggleGroup(tg);
        r3.setToggleGroup(tg);
  
        // add label
        r.getChildren().add(l);
        r.getChildren().add(r1);
        r.getChildren().add(r2);
        r.getChildren().add(r3);
        r.getChildren().add(l2);
  
        // create a scene
        Scene sc = new Scene(r, 200, 200);
  
        // add a change listener
        tg.selectedToggleProperty().addListener(new ChangeListener<Toggle>() 
        {
            public void changed(ObservableValue<? extends Toggle> ob, 
                                                    Toggle o, Toggle n)
            {
  
                RadioButton rb = (RadioButton)tg.getSelectedToggle();
  
                if (rb != null) {
                    String s = rb.getText();
  
                    // change the label
                    l2.setText(s + " selected");
                }
            }
        });
  
        // set the scene
        s.setScene(sc);
  
        s.show();
    }
  
    public static void main(String args[])
    {
        // launch the application
        launch(args);
    }
}