Question

Create a JavaFX application that lets the user enter the food charge for a meal at a restaurant. For example, if $20 is entered as a food charge for a meal then $3.6 should be displayed for the tip, $1.4 should be displayed for sales tax, and $25 should be displayed as a total of all three amounts. Modification 1: create a text box (not a pop up) for the user to enter a percent tip (don't just hardcode it to 18%) Modification 2: create a text box (not a pop up) for the user to enter a percent sales tax (don't just hardcode it to 7%)

Answer 1

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;

import javafx.stage.Stage;


public class Bill extends Application {

   
    public static void main(String[] args) {
         launch(args);
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
         
         GridPane grid = new GridPane();
         grid.setPadding(new Insets(10, 10, 10, 10));
         grid.setVgap(5);
         grid.setHgap(5);
         TextField foodCharge = new TextField(" Food Charge");
         TextField tip = new TextField(" Enter Tip ");
         TextField salesTax = new TextField(" Sales Tax ");
         foodCharge.setEditable(false);
         tip.setEditable(false);
         salesTax.setEditable(false);
         
         TextField foodChargeValue = new TextField();
         TextField tipValue = new TextField();
         TextField salesTaxValue = new TextField();
         
         foodChargeValue.setPromptText(" Enter Food Charge ");
         tipValue.setPromptText(" Enter Tip Percentage ");
         salesTaxValue.setPromptText(" Enter Sales Tax Percentage ");
         
         
         grid.add(foodCharge, 0, 0);
         grid.add(tip, 0, 1);
         grid.add(salesTax, 0, 2);
        
         grid.add(foodChargeValue, 1, 0);
         grid.add(tipValue, 1, 1);
         grid.add(salesTaxValue, 1, 2);
         
         EventHandler<ActionEvent> event = new EventHandler<ActionEvent>() { 
            public void handle(ActionEvent e) 
            {  
                TextField tipShow = new TextField();
                TextField salesTaxShow = new TextField();
                TextField totalShow = new TextField();
                if(!foodChargeValue.getText().isEmpty() && !tipValue.getText().isEmpty() && !salesTaxValue.getText().isEmpty()) {
                   double tipPercentage = Double.parseDouble(tipValue.getText().trim());
                   double salesTaxPercentage = Double.parseDouble(salesTaxValue.getText().trim());
                   double foodPrice = Double.parseDouble(foodChargeValue.getText().trim());

                   double tipAmount = (foodPrice * tipPercentage)/100;
                   double salesTaxAmount = (foodPrice * salesTaxPercentage)/100;

                   double totalAmount = foodPrice + tipAmount + salesTaxAmount;

                   TextField tipLabel = new TextField(" Tip ");
                   TextField salesTaxLabel = new TextField(" Sales Tax ");
                   TextField totalLabel = new TextField(" Total ");

                   tipLabel.setEditable(false);
                   salesTaxLabel.setEditable(false);
                   totalLabel.setEditable(false);
                   
                   
                   grid.add(tipLabel, 0, 4);
                   grid.add(salesTaxLabel, 0, 5);
                   grid.add(totalLabel, 0, 6);


                   tipShow.setEditable(false);
                   salesTaxShow.setEditable(false);
                   totalShow.setEditable(false);

                   
                   tipShow.setText(String.valueOf(tipAmount));
                   salesTaxShow.setText(String.valueOf(salesTaxAmount));
                   totalShow.setText(String.valueOf(totalAmount));

                   grid.add(tipShow, 1, 4);
                   grid.add(salesTaxShow, 1, 5);
                   grid.add(totalShow, 1, 6);
                } else {
                    Alert alert = new Alert(Alert.AlertType.ERROR);
                    alert.setTitle("Error");
                    alert.setContentText("Please Enter correct value");
                    alert.show();
                }
            }
         };
         
         
         Button btn = new Button("Calculate");
         grid.add(btn, 0, 3);
         btn.setOnAction(event);
         Scene sc = new Scene(grid, 500, 500);
         primaryStage.setScene(sc);
         primaryStage.show();
    }
}