java - 单击我的按钮 Swing Java 后不显示任何内容

Question

(小心 SoMania 捕获了我!)所以我的标题不是很好，因为它很难解释我的问题。所以我的问题是在我点击我的应用程序上的按钮之后我删除按钮并清除我的屏幕它需要显示一些文本区域进行一些计算。但是，当我单击按钮并删除所有内容时，我需要最大化或调整窗口大小以使 TextArea 和标 checkout 现。谁能帮帮我？

这是我的代码:

package igrica;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Cijena{
    JButton button;
    JFrame frame;
   JTextField field;
    JPanel panel;
   JLabel label;
   JLabel label2;
   JTextField field2;
   JButton button2;
   JLabel rjesenje2;

public static void main(String [] args) {
    Cijena gui = new Cijena();
    gui.go();
} 

public void go() {
    try {
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
    }catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {}
    panel = new JPanel();
    rjesenje2 = new JLabel();
    label = new JLabel("Upisite cijenu bez popusta: ");
    label2 = new JLabel("Upisite cijenu s popustom: ");
    field2 = new JTextField(20);
    panel.setBackground(Color.white);
    button2 = new JButton("Izracunaj");
    //panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));
    frame = new JFrame("Matematicki programi za apartmane");
    button = new JButton("Razlika u cijeni");
    button.addActionListener(new CijenaListener());
    button2.addActionListener(new ButtonListener());
    field = new JTextField(20);
    field.addActionListener(new TextListener());

    frame.getContentPane().add(BorderLayout.NORTH, button);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(300, 300);
    frame.setVisible(true);
    frame.setLayout(new BorderLayout());
}

class CijenaListener implements ActionListener {
    public void actionPerformed(ActionEvent event) {
        frame.repaint();
        frame.getContentPane().remove(button);
        frame.getContentPane().add(field);
        frame.getContentPane().add(panel);
        //frame.getContentPane().add(label);
        //frame.getContentPane().add(label2);
        //frame.getContentPane().add(field2);
        //TestPane pane = new TestPane();
        //pane.TestPane();
        panel.add(label);
        panel.add(field);
        panel.add(label2);
        panel.add(field2);
        panel.add(button2);
    }
}
class TextListener implements ActionListener {
    public void actionPerformed(ActionEvent event) {
        String text = field.getText();
        field.setText("");
    }
}
class ButtonListener implements ActionListener {
    public void actionPerformed(ActionEvent ev) {
        String input1 = field.getText();
        String input2 = field2.getText();
        field.setText("");
        field2.setText("");
        int number1 = Integer.parseInt(input1);
        int number2 = Integer.parseInt(input2);

        double rjesenje = (double)number2 / number1;
        rjesenje *= 100;
        int r = 100 - (int)rjesenje;
        //System.out.println(number1 + " " + number2);
        String solution = Integer.toString(r);
        rjesenje2.setText(solution + "%");
        panel.add(rjesenje2);
    }
}

class MyDrawPanel extends JPanel {
    public void paintComponent(Graphics g) {
        g.fillRect(0, 0, getWidth(), getHeight());
    }
}

}

Answer 1

在 actionPerformed 方法结束时调用 frame.revalidate();。