嘗試使用包含兩個 JButton 的 JPanel 制作 JFrame

Question

我是這里的初學者，我正在嘗試制作一個 GUI 來顯示兩個按鈕，addCard 和 deleteCard。 但是，編譯器顯示錯誤，我似乎找不到錯誤。 先感謝您！

package studyfast;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Scratch{
    JFrame projectFrame = new JFrame();
    projectFrame.setSize(1000, 600);
    projectFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

    JPanel panelEditCard = new JPanel();

    JButton addCard = new JButton();
    JButton deleteCard = new JButton();

    panelEditCard.add(addCard);
    panelEditCard.add(deleteCard);

    projectFrame.add(panelEditCard);
    projectFrame.setVisible(true);

    public static void main(String[] args){
        new Scratch();
    }
}

Answer 1

您需要將代碼移動到constructor內的Scratch類中

package studyfast;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Scratch 
{
    JFrame projectFrame = new JFrame();
    JPanel panelEditCard = new JPanel();
    JButton addCard = new JButton();
    JButton deleteCard = new JButton();

    public Scratch()
    {
        projectFrame.setSize(1000, 600);
        projectFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);   

        panelEditCard.add(addCard);
        panelEditCard.add(deleteCard);

        projectFrame.add(panelEditCard);
        projectFrame.setVisible(true);
      }

   public static void main(String[] args) 
   {
       new Scratch();
   }
}