程序不将Jframe TextField值与其他类别生成的数字进行比较

Question

我制作了一些随机数学生成器，它给出了2个随机数和一个随机操作员，但是当我在“确定”按钮中调用检查结果方法时，我总是会得到“ errado”（“错误”）字符串，这意味着它无法正确比较它呈现出任何数学问题的结果，Textfield的价值。在这里两个课程中留下相关的代码，并提供有关我有问题的评论和2个以易于理解的评论。帮助您表示感谢！

public class geraAritmetica {
    ArrayList<Integer> nums = new ArrayList();
    int a;
    char ops = '?';
    int max = 10;
    int min = 1;
    int range = max - min + 1;
    int res;

    Random r = new Random();
    
    public int gerarNums(){
        for(int i = 0; i<10; i++){
            a = (int) (Math.random()*range) + min;
            nums.add(a);
        }
        return a;
    }
    
    public char gerarOps(){
        switch(r.nextInt(4)){
            case 1 : ops = '+';
                     res = nums.get(0) + nums.get(1);
            break;
            case 2: ops = '-';
                    res = nums.get(0) - nums.get(1);
                    break;
            case 3: ops = '*';
                    res = nums.get(0) * nums.get(1);
                    break;
            case 4: ops = '/';
                    res = nums.get(0) / nums.get(1);
                    break;    
            
            default: ops = '+';
                     res = nums.get(0) + nums.get(1);
            break;
        }
        return ops;
    }
        
        public boolean checkRes(){   //everytime I call this method always get the same string "Errado" ("Wrong") in the label.          
            if(Integer.parseInt(FrameEnsinoAritmetica.jTextField1.getText()) == res){
                FrameEnsinoAritmetica.jLabel2.setText("Correto!");
                return true;
            }
            else FrameEnsinoAritmetica.jLabel2.setText("Errado!");
            return false;
        }
        
    }

public class FrameEnsinoAritmetica extends javax.swing.JFrame {
   geraAritmetica a = new geraAritmetica(); //creating object of class at the start of my JFrame class
    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {  //generating numbers and operator (it prints fine in another label)                                       

        int b = a.gerarNums();
        int c = a.gerarNums();
        char s = a.gerarOps();
        
        jLabel1.setText(b + " " +s+ " " + c);
    }                                        

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                            
        a.checkRes(); //everytime I call this method always get the same string "Errado" ("Wrong") in the label.          
    }  

Answer 1

您似乎正在引用frameensinoaritmetica类直接不是您在屏幕上看到的FrameensinoaritMetica jframe的实际实例。例如，在另一个类中使用此内容不会介绍您在屏幕上看到的帧：

String text = FrameEnsinoAritmetica.jTextField1.getText();

但是使用此框架将有效：

String text = yourInstanceOfEnsinoAritmetica.jTextField1.getText();

为了解决此问题，我们可以通过FrameSinoAritMetica的当前实例，该实例在屏幕上显示在checkres方法中，我们通过修改checkres喜欢这样做，在方法中，我们用frame> frame> frameensinoaritmetica用frame要参考当前实例：

    public boolean checkRes(FrameEnsinoAritmetica frame){   //everytime I call this method always get the same string "Errado" ("Wrong") in the label.          
        if(Integer.parseInt(frame.jTextField1.getText()) == res){
            frame.jLabel2.setText("Correto!");
            return true;
        }
        else frame.jLabel2.setText("Errado!");
        return false;
    }

然后，我们只需更新jbutton1ActionPerformed方法以传递this它是frame> frame> frame> framesinoaritmetica /代码>进入更新的checkres方法：

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                            
    a.checkRes(this); //everytime I call this method always get the same string "Errado" ("Wrong") in the label.          
} 

Answer 2

修复第2部分（用于未正确计算的RES）

public class FrameEnsinoAritmetica extends javax.swing.JFrame {
   geraAritmetica a = new geraAritmetica();
   public static int b;
   public static int c;
    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         

        b = a.gerarNums();
        c = a.gerarNums();
        char s = a.gerarOps(this);
        
        jLabel1.setText(b + " " +s+ " " + c + " ");
    }  

public class geraAritmetica {
    ArrayList<Integer> nums = new ArrayList();
    int a;
    char ops = '?';
    int max = 10;
    int min = 1;
    int range = max - min + 1;
    public static int res;

    Random r = new Random();

    public int gerarNums(){
        for(int i = 0; i<10; i++){
            a = (int) (Math.random()*range) + min;
            nums.add(a);
        }
        return a;
    }

    public char gerarOps(FrameEnsinoAritmetica frame){
        switch(r.nextInt(4)){
            case 1 : ops = '+';
                     res = frame.b + frame.c; //checking both variables directly from JFrame class instead of getting through index from ArrayList.
                    break;
            case 2: ops = '-';
                    res = res = frame.b - frame.c;
                    break;
            case 3: ops = '*';
                    res = frame.b * frame.c;
                    break;
            case 4: ops = '/';
                    res = frame.b / frame.c;
                    break;    
            
            default: ops = '+';
                     res = frame.b + frame.c;
            break;
        }
        return ops;
    }
        
        public boolean checkRes(FrameEnsinoAritmetica frame){
            if(Integer.parseInt(frame.jTextField1.getText()) == res){
                frame.jLabel2.setText("Correto!");
                return true;
            }
            else frame.jLabel2.setText("Errado!");
            return false;
        }
        
    }