Question

我正在为初学者的Java课程制作一个卡路里计数器程序，我真的无法掌握ArrayList字的方式。基本上，该计划由七个类组成：Food，FoodEaten，Activity，ActivityPerformed，Tracker，TrackerGUI和{{1 }}

这些是GUI的以下命令：

添加食物：创建一个新对象并将其放入foodBase TrackerApp;
```
ArrayList
```
追踪食物：检查食物是否在食物基地public void addFood(String foodName, double calories) { foodBase.add(new Food(foodName, calories)); }。如果是，则将对象添加到foodEaten ArrayList
```
Arraylist
```
打印报告：打印public Food getFood(String name){ for(int i = 0; i < foodBase.size(); i++) { if(foodBase.get(i).getName().equals(name)) return foodBase.get(i) } } public void trackFood(String foodName, double servings) { Food f = getFood(name); foodEaten.add(new FoodEaten(Food f, calories)); }数组
中记录的所有项目
```
FoodEaten
```

我有三个public String printReport() { String lifestyleReport = ""; lifestyleReport +=(Food Consumed: \n"); lifestyleReport += getFoodEaten(); lifestyleReport +=(Total Calories Consumed: this.caloriesGained + kcal \n"); }：foodField，caloriesField，quantityField

JTextFields

以及以下内容：

private JTextField foodField;
private JTextField caloriesField;
private JTextField quantityField;

和

public class Food implements ActionListener {
    public void actionPerformed (ActionEvent ae) {
        double calories = Double.parseDouble(caloriesField.getText().replaceAll(",",""));
        String newFood = activityField.getText();
        if(calories < 0) {
            textArea.append("Calories cannot be negative. \n\n"); 
        }
        else {
            tracking.addFood(newFood, calories);
            textArea.append(newFood + " with " + calories + " calories added to database! \n");
        }
    }
}

现在很明显我做错了什么（因为这一切都没有用）。

如何让一切正常？

基于GUI的用户输入工作arraylist

0 个答案: