import java.awt.event.ActionEvent;
import java.beans.EventHandler;
import java.util.ArrayList;
import java.util.Arrays;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.geometry.Insets;
import javafx.geometry.VPos;
import javafx.scene.Scene;
import javafx.scene.control.Alert;
import javafx.scene.control.Alert.AlertType;
import javafx.scene.control.Button;
import javafx.scene.control.ComboBox;
import javafx.scene.control.Label;
import javafx.scene.control.PasswordField;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.text.Font;
import javafx.stage.Stage;

/**
* this is the main Model object The first View that the "Invoice" class puts up
* on being created is a “LoginView” screen, It should have the title "Mom and
* Pop’s Clothing Store". Once the user enters a user name and password on the
* login screen, an appropriate method in the "Invoice" class will be called.
* This method will look through a list of authorized users that the "Invoice"
* class maintains, and successfully log the current user (i.e., an authorized
* store clerk) in or not. Once the clerk is logged in the Main Invoice Screen
* (as shown in the mockup above) should be displayed. Once the clerk is logged
* in the Main Invoice Screen (as shown in the mockup above) should be displayed
*/
public class Invoice extends Application {

/**
* Shirts, Pants, Ties and/or Shoes items
*/
private double salesTax;
private Font font;
private ArrayList userNames;
private ArrayList userPassword;
private ArrayList salesTaxValues;
private Button backButton;
private Button calcButton;
private Button logInButton;
private Button cancelButton;

private Label userNameLabel;
private Label passWordLabel;
private Label shirtsLabel;
private Label pantsLabel;
private Label tiesLabel;
private Label shoesLabel;
private Label salesTaxLabel;
private Label totalBillLabel;

private TextField userNameTextField;
private PasswordField passWordTextField;
private TextField shirtsTextField;
private TextField pantsTextField;
private TextField tiesTextField;
private TextField shoesTextField;
private TextField totalBillsTextField;

private ComboBox salesTaxComboBox;
private Stage primaryStage;
private Scene scene;
private GridPane root;

public Invoice() {
}

@Override
public void start(Stage primaryStage) throws Exception {
   // initalize variables
   this.font = new Font("Tahoma", 18);
   this.salesTax = 0.0;
   initializeSalesTaxValues();
   createUsers();
   creatButtons();
   createLabels();
   createTextFields();
   createComboBox();
   this.primaryStage = primaryStage;
   createLoginScreen();

}

/**
* this function initialize Sales Tax Values in range from 3.00 to 9.50, in
* increments of 0.25
*/
public void initializeSalesTaxValues() {
   this.salesTaxValues = new ArrayList();
   for (double i = 3; i <= 9.50; i += .25) {
         this.salesTaxValues.add(i);
   }
}

/**
* this function create and display Login Screen
*/
private void createLoginScreen() {
   this.userNameTextField.setText("");
   this.userNameTextField.setPromptText("Your user name");
   this.passWordTextField.setText("");
   this.passWordTextField.setPromptText("Your password");
   this.root = new GridPane();
   this.root.setVgap(30);
   this.root.setHgap(30);
   this.root.setPadding(new Insets(10));
   this.root.add(this.userNameLabel, 0, 0);
   this.root.add(this.passWordLabel, 0, 1);
   this.root.add(this.userNameTextField, 1, 0);
   this.root.add(this.passWordTextField, 1, 1);
   this.root.add(this.cancelButton, 0, 2);
   this.root.add(this.logInButton, 1, 2);
   GridPane.setValignment(this.userNameLabel, VPos.TOP);
   this.primaryStage.setTitle(
            "Mom and Pop’s Clothing Store");
   this.scene = scene = new Scene(root, 500, 200);
   this.primaryStage.setScene(this.scene);
   this.primaryStage.setResizable(false);
   this.primaryStage.show();
}

/**
* this function create and display Main Invoice Screen Mockup
*/
private void createMainInvoiceScreen() {

   this.shirtsTextField.setText("");
   this.pantsTextField.setText("");
   this.tiesTextField.setText("");
   this.shoesTextField.setText("");
   this.totalBillsTextField.setText("");
   this.salesTax = (double)this.salesTaxValues.get(0);
   this.salesTaxComboBox.setValue(this.salesTaxValues.get(0));
   this.root = new GridPane();
   this.root.setVgap(30);
   this.root.setHgap(10);
   this.root.setPadding(new Insets(10));
   this.root.add(this.shirtsLabel, 0, 0);
   this.root.add(this.shirtsTextField, 1, 0);

   this.root.add(this.pantsLabel, 0, 1);
   this.root.add(this.pantsTextField, 1, 1);

   this.root.add(this.tiesLabel, 0, 2);
   this.root.add(this.tiesTextField, 1, 2);

   this.root.add(this.shoesLabel, 0, 3);
   this.root.add(this.shoesTextField, 1, 3);

   this.root.add(this.salesTaxLabel, 0, 4);
   this.root.add(this.salesTaxComboBox, 1, 4);

   this.root.add(this.totalBillLabel, 0, 5);
   this.root.add(this.totalBillsTextField, 1, 5);

   this.root.add(this.calcButton, 0, 6);
   this.root.add(this.backButton, 1, 6);
   GridPane.setValignment(this.shirtsLabel, VPos.TOP);
   this.primaryStage.setTitle(
            "Mom and Pop’s Clothing Store");
   this.scene = scene = new Scene(root, 500, 500);
   this.primaryStage.setScene(this.scene);
   this.primaryStage.setResizable(false);
   this.primaryStage.show();
}

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