知道为什么JFrame会出现这种故障吗？

Question

我的JFrame出现了一个小问题。当我运行我的代码时，代码会先取8个值，然后把它们画到jframe窗口上，它确实是这样做了，但是这个窗口似乎捕捉到了我的windows桌面上框架后面的任何东西。所以，你可以看到在图片中，它捕捉到了我的Jintelligence框，而在另一张图片中，它捕捉到了我的壁纸，这就是背景。我只是想要一个普通的正常背景。不知道为什么会出现这种情况。有什么想法吗？

> import javax.swing.*;
import java.awt.*;
import java.lang.*;


public class Distance extends JFrame {
    String longer;
    String input;
    int line1_x1, line1_y1, line1_x2, line1_y2;
    int line2_x1, line2_y1, line2_x2, line2_y2;
    double l1distance;
    double l2distance;
    double distl1;
    double distl2;

    public static void main(String[] args) {
        Distance frame = new Distance();
        frame.setSize(600, 600);
        frame.setTitle("LINE DRAWER");
        frame.getvalues();
        frame.getdistance();
        frame.getlongest();
        frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
    public void getvalues () {
        //Line 1

        input = JOptionPane.showInputDialog("Enter the X1 coordinate for Line 1 here:");
        line1_x1 = Integer.parseInt(input);
        input = JOptionPane.showInputDialog("And the Y1 coordinate for Line 1:");
        line1_y1 = Integer.parseInt(input);
        input = JOptionPane.showInputDialog("Enter the X2 coordinate for Line 1 here:");
        line1_x2 = Integer.parseInt(input);
        input = JOptionPane.showInputDialog("Plus the Y2 coordinate for Line 1:");
        line1_y2 = Integer.parseInt(input);
        //Line 2
        input = JOptionPane.showInputDialog("Now, enter the X1 coordinate the 2nd line:");
        line2_x1 = Integer.parseInt(input);
        input = JOptionPane.showInputDialog("And the Y1 coordinate for the 2nd line:");
        line2_y1 = Integer.parseInt(input);
        input = JOptionPane.showInputDialog("Then the X2 coordinate here:");
        line2_x2 = Integer.parseInt(input);
        input = JOptionPane.showInputDialog("And lastly, the Y2 coordinate:");
        line2_x2 = Integer.parseInt(input);
    }
    public void getdistance() {
        distl1 = Math.pow((line1_y2 - line1_y1),2) + Math.pow((line1_x2 - line1_x1),2);
        distl2 = Math.pow((line2_y2 - line2_y1),2) + Math.pow((line2_x2 - line2_x1),2);
        //Math.sqrt((y2 - y1) * (y2 - y1) + (x2 - x1) * (x2 - x1));\
         l1distance = Math.abs(Math.floor(Math.sqrt(distl1)));
         l2distance = Math.abs(Math.floor(Math.sqrt(distl2)));
    }
    public void getlongest(){
        if(l1distance > l2distance){
        longer = "Line One";
        }
        else if(l1distance == l2distance){
            longer = "The Lines are Equal";
        }
        else if(l2distance > l1distance){
            longer = "Line Two";
        }
    }
    public void paint(Graphics g) {
        Graphics2D g2d = (Graphics2D) g;
        g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
        g2d.drawLine(line1_x1, line1_y1, line1_x2, line1_y2);
        g2d.drawString("Line 1 Origin: (" + line1_x1 + "," + line1_y1 +")", line1_x1-15, line1_y1-15);
        g2d.drawString("Line 1 End: (" + line1_x2 + "," + line1_y2 +")", line1_x2+15, line1_y2+ 15);
        g2d.drawLine(line2_x1, line2_y1, line2_x2, line2_y2);
        g2d.drawString("Line 2 Origin: (" + line2_x1 + "," + line2_y1 +")", line2_x1-15, line2_y1-15);
        g2d.drawString("Line 2 End: (" + line2_x2 + "," + line2_y2 +")", line2_x2+15, line2_y2+ 15);
        g2d.setColor(Color.red);
        g2d.setFont(new Font("Batang", Font.BOLD, 10));
        g2d.drawString("Line 1's Distance is: " + l1distance + ".", 50,400);
        g2d.drawString("Line 2's Distance is: " + l2distance + "." ,50,430);
        g2d.drawString("The longer line is: " + longer + "." ,50,450);

    }
}

Answer 1

对不起，我是JFrame的新手，所以这可能没有用，但你是否尝试过以下方法 frame. setBackground(Color.WHITE)?