Dfyjkt

I have 4 text fields which I have already formatted to receive only integer values.

I now want the "Capital" field to receive in real time the sum of all the other fields each time they have their value updated;

I tried the binding but I do not know too much, I also tried to add listener on the bottom fields to update the value of the "capital" but it does not react as I wish

The next block of code shows how to bind three TextFields:

import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.beans.binding.StringBinding;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class Test extends Application 

 @Override
 public void start(final Stage primaryStage) 

 final VBox vBox = new VBox();

 final TextField textField1 = new TextField();
 final TextField textField2 = new TextField();
 final TextField textField3 = new TextField();
 final TextField textField4 = new TextField();

 final StringBinding createStringBinding = Bindings.createStringBinding(()-> 
 String valueTextField1 = (textField1.getText().isEmpty()) ? "0" : textField1.getText();
 String valueTextField2 = (textField2.getText().isEmpty()) ? "0" : textField2.getText();
 String valueTextField3 = (textField3.getText().isEmpty()) ? "0" : textField3.getText();
 return String.valueOf(Integer.valueOf(valueTextField1) + Integer.valueOf(valueTextField2) + Integer.valueOf(valueTextField3));, textField1.textProperty(), textField2.textProperty(), textField3.textProperty());

 textField4.textProperty().bind(createStringBinding);

 vBox.getChildren().add(textField1);
 vBox.getChildren().add(textField2);
 vBox.getChildren().add(textField3);
 vBox.getChildren().add(textField4);

 final Scene scene = new Scene(vBox, 400, 200);
 primaryStage.setScene(scene);
 primaryStage.show();
 

 public static void main(final String args) 
 launch(args);
 

You can use Bindings.createStringBinding to achieve this, remember to include all 4 text fields in the dependencies parameter