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无法获取第二个视图列表以列表作为参数

无论我如何措辞或放置在列表视图中的内容如何,​​都无法获取第二个创建的视图列表以接受作为参数添加的“ cartItems”值项。尝试使用.getitems(cartItems),但不会。是他们的其他任何声明或方式吗?我可以这样说,以便使用“添加”按钮添加的思想移至第二个列表以进行结帐 完整代码

package shoppingcart1;
import java.io.File;
import java.io.FileNotFoundException;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.ListView;
import javafx.scene.layout.VBox;
import javafx.scene.layout.HBox;
import javafx.geometry.Pos;
import javafx.geometry.Insets;
import javax.swing.*;
import java.awt.List;
import java.awt.event.ActionListener;
import java.text.DecimalFormat;
import java.util.Scanner;


public class ShoppingCart1 extends Application
{
    private Label answer;
    private Label price;
    ListView <String> listView;
    ListView <String> listView2;
    private String[] listArray = new String[7];
    private String[] listArray2 = new String[7];
    private List cartItems = new List();

    private final double salesTax = 0.07;

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

    @Override
    public void start(Stage primaryStage) throws FileNotFoundException
    {
        answer = new Label("Price: ");
        price = new Label("");
        String line;
        int index = 0;
        File file = new File("BookPrices.txt");
        Scanner fileReader = new Scanner(file);

        while (fileReader.hasNext())
        {
            line = fileReader.nextLine();
            String[] titles = line.split(",");
            listArray[index] = titles[0];
            index++;
        }
        //list view items book
        listView = new ListView < > ();
        listView.setPrefSize(200, 170);
        listView.getItems().addAll(listArray);

        //list view items book
        listView2 = new ListView < > ();
        listView2.setPrefSize(200, 170);
        listView2.getItems();


        // create label to display the selection
        Label selectedNameLabel = new Label("Select a Book");
        Label price = answer;

        //Button for selection
        Button addButton = new Button("Add to Cart");
        addButton.setOnAction(new AddButtonListener());

        //Delete button
        Button removeButton = new Button("Remove Item");
        removeButton.setOnAction(new RemoveButtonListener());

        //Delete button
        Button clearButton = new Button("Clear All");
        clearButton.setOnAction(new ClearButtonListener());

        //Checkout
        Button checkoutButton = new Button("Check Out");
        checkoutButton.setOnAction(new CheckoutButtonListener());

        //Controls to HBox
        HBox hbox = new HBox(listView, listView2);

        //Controls to HBox2
        HBox hbox2 = new HBox(10, addButton, removeButton, clearButton, checkoutButton);
        hbox2.setAlignment(Pos.CENTER);

        //Controls to VBox
        VBox vbox = new VBox(10, hbox, selectedNameLabel,
                price, hbox2);
        vbox.setPadding(new Insets(10));
        vbox.setAlignment(Pos.CENTER);

        //Show
        Scene scene = new Scene(vbox);
        primaryStage.setScene(scene);
        primaryStage.show();
    }


    // Add button
    public class AddButtonListener implements EventHandler < ActionEvent >
    {
        @Override
        public void handle(ActionEvent e)
        {
            String value = listView.getSelectionModel().getSelectedItem();
            cartItems.add(value);
           // answer.setText("Price: " + Calc());
        }

    }
    // Subtract Button
    public class RemoveButtonListener implements EventHandler < ActionEvent >
    {

        @Override
        public void handle(ActionEvent e)
        {
            String value = listView.getSelectionModel().getSelectedItem();
            try {
                cartItems.remove(value);
                //answer.setText("Price: " + Calc());
            }
            catch (IllegalArgumentException ex) {
                //do nothing
            }
        }
    }
        //Clearbutton
        public class ClearButtonListener implements EventHandler < ActionEvent > 
    {

        @Override
        public void handle(ActionEvent e) 
        {
                    cartItems.removeAll();
                    answer.setText("Price: " + Calc());
        }
    }

        //Checkout
        public class CheckoutButtonListener implements EventHandler < ActionEvent > 
    {
        @Override
        public void handle(ActionEvent e) 
        {
                    answer.setText("Price: " + Calc());
        }
    }

    // Button Calculations
    private String Calc() {
        String line;
        double totalCost = 0.0, costOfItem = 0.0;
        File file = new File("BookPrices.txt");
        Scanner fileReader = null;
        try
        {
            fileReader = new Scanner(file);
        }
        catch (FileNotFoundException el)
        {
            el.printStackTrace();
        }

        while (fileReader.hasNextLine())
        {
            line = fileReader.nextLine();
            String[] cost = line.split(",");

            String title = cost[0];
            costOfItem = Double.parseDouble(cost[1]);

            for (int i = 0; i < cartItems.getItemCount(); i++)
            {
                if (title.equals(cartItems.getItem(i)))
                    totalCost += costOfItem;
            }
        }

        DecimalFormat myFormatter = new DecimalFormat("###.##");

        return myFormatter.format((salesTax * totalCost) + totalCost).toString();
    }
}

问题来源:Stack Overflow

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montos 2020-03-23 17:08:11 465 0
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  • 我认为您代码的主要问题是cartItems类的成员ShoppingCart1是java.awt.List。您不能混合使用AWT和JavaFX组件。在下面的代码中,我将其更改为java.util.List。

    在下面的代码中,我进行了最少的更改,以使按钮能够执行我认为希望的操作。我不会说以下代码构成了完整的JavaFX应用程序。我的意图(也是希望)是,它可以帮助您克服目前遇到的障碍。

    public class ShoppingCart1 extends Application
    {
        private Label answer;
        private Label price;
        ListView <String> listView;
        ListView <String> listView2;
        private String[] listArray = new String[7];
        private String[] listArray2 = new String[7];
        private List<String> cartItems = new ArrayList<>();
    
        private final double salesTax = 0.07;
    
        public static void main(String[] args) throws FileNotFoundException
        {
            launch(args);
        }
    
        @Override
        public void start(Stage primaryStage) throws FileNotFoundException
        {
            answer = new Label("Price: ");
            price = new Label("");
            String line;
            int index = 0;
            File file = new File("BookPrices.txt");
            try (Scanner fileReader = new Scanner(file))
            {
                while (fileReader.hasNext())
                {
                    line = fileReader.nextLine();
                    String[] titles = line.split(",");
                    listArray[index] = titles[0];
                    index++;
                }
            }
            //list view items book
            listView = new ListView<>();
            listView.setPrefSize(200, 170);
            listView.getItems().addAll(listArray);
    
            //list view items book
            listView2 = new ListView<>();
            listView2.setPrefSize(200, 170);
            listView2.getItems();
    
            // create label to display the selection
            Label selectedNameLabel = new Label("Select a Book");
            Label price = answer;
    
            //Button for selection
            Button addButton = new Button("Add to Cart");
            addButton.setOnAction(new AddButtonListener());
    
            //Delete button
            Button removeButton = new Button("Remove Item");
            removeButton.setOnAction(new RemoveButtonListener());
    
            //Delete button
            Button clearButton = new Button("Clear All");
            clearButton.setOnAction(new ClearButtonListener());
    
            //Checkout
            Button checkoutButton = new Button("Check Out");
            checkoutButton.setOnAction(new CheckoutButtonListener());
    
            //Controls to HBox
            HBox hbox = new HBox(listView, listView2);
    
            //Controls to HBox2
            HBox hbox2 = new HBox(10, addButton, removeButton, clearButton, checkoutButton);
            hbox2.setAlignment(Pos.CENTER);
    
            //Controls to VBox
            VBox vbox = new VBox(10, hbox, selectedNameLabel, price, hbox2);
            vbox.setPadding(new Insets(10));
            vbox.setAlignment(Pos.CENTER);
    
            //Show
            Scene scene = new Scene(vbox);
            primaryStage.setScene(scene);
            primaryStage.show();
        }
    
        // Add button
        public class AddButtonListener implements EventHandler < ActionEvent >
        {
            @Override
            public void handle(ActionEvent e)
            {
                String value = listView.getSelectionModel().getSelectedItem();
                listView2.getItems().add(value);
                cartItems.add(value);
                answer.setText("Price: " + Calc());
            }
        }
        // Subtract Button
        public class RemoveButtonListener implements EventHandler < ActionEvent >
        {
    
            @Override
            public void handle(ActionEvent e)
            {
                String value = listView.getSelectionModel().getSelectedItem();
                try {
                    cartItems.remove(value);
                    listView2.getItems().remove(value);
                    answer.setText("Price: " + Calc());
                }
                catch (IllegalArgumentException ex) {
                    //do nothing
                }
            }
        }
        //Clearbutton
        public class ClearButtonListener implements EventHandler < ActionEvent > 
        {
    
            @Override
            public void handle(ActionEvent e) 
            {
                cartItems.clear(); //removeAll();
                listView2.getItems().clear();
                answer.setText("Price: " + Calc());
            }
        }
    
        //Checkout
        public class CheckoutButtonListener implements EventHandler < ActionEvent >
        {
            @Override
            public void handle(ActionEvent e) 
            {
                answer.setText("Price: " + Calc());
            }
        }
    
        // Button Calculations
        private String Calc() {
            String line;
            double totalCost = 0.0, costOfItem = 0.0;
            File file = new File("BookPrices.txt");
            Scanner fileReader = null;
            try
            {
                fileReader = new Scanner(file);
            }
            catch (FileNotFoundException el)
            {
                el.printStackTrace();
            }
    
            while (fileReader.hasNextLine())
            {
                line = fileReader.nextLine();
                String[] cost = line.split(",");
    
                String title = cost[0];
                costOfItem = Double.parseDouble(cost[1]);
    
                for (int i = 0; i < cartItems.size() /*getItemCount()*/; i++)
                {
                    if (title.equals(cartItems.get/*Item*/(i)))
                        totalCost += costOfItem;
                }
            }
            DecimalFormat myFormatter = new DecimalFormat("###.##");
            return myFormatter.format((salesTax * totalCost) + totalCost).toString();
        }
    }
    

    回答来源:Stack Overflow

    2020-03-23 17:08:52
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