package calculator;

import javafx.application.Application;

import javafx.event.ActionEvent;

import javafx.event.EventHandler;

import javafx.scene.Scene;

import javafx.scene.control.Button;

import javafx.scene.layout.StackPane;

import javafx.stage.Stage;

public class Gui extends Application {

InputHandler inputhandler = new InputHandler();

Button add = new Button();

@Override
public void start(Stage primaryStage) throws Exception {
    primaryStage.setTitle("HackCalc");


    add.setText("+");
    add.setOnAction(inputhandler);


    StackPane layout = new StackPane();
    layout.getChildren().add(add);

    Scene scene = new Scene(layout, 330, 500);

    primaryStage.setScene(scene);
    primaryStage.show();
}


}

package calculator;

import javafx.event.ActionEvent;
import javafx.event.EventHandler;



public  class InputHandler extends Gui implements EventHandler<ActionEvent>{




@Override
public void handle(ActionEvent event) {
    if(event.getSource()== add){
        System.out.println("InputHandler works");
    }
}
}