java - 我怎样才能创建一个 JButton？

Question

在创建 JButton 并将其设置为 Visible 之后，我不明白为什么我在窗口中看不到它。:/

import java.awt.Color;

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

public class Window extends JFrame{

    public static int width = 350;
    public static int height  = 480;

    public static void main (String args[]) {
        JFrame window = new JFrame();
        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.setSize(width, height);
        window.setVisible(true);
        window.setTitle("Virtual World");
        window.setLocationRelativeTo(null);
        window.setResizable(false);
        window.getContentPane().setBackground(new Color(80,80,240));

        JButton enter = new JButton();
        enter.setVisible(true);


    }

}       

Answer 1

正如@Tunaki 在评论中已经提到的，您需要先将 JButton 添加到面板。

试试这个

public class Test extends JFrame{

    public static int width = 350;
    public static int height  = 480;

    public static void main (String args[]) {
        JFrame window = new JFrame();
        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.setSize(width, height);

        window.setTitle("Virtual World");
        window.setLocationRelativeTo(null);
        window.setResizable(false);
        window.getContentPane().setBackground(new Color(80,80,240));

        JButton enter = new JButton("Ok");
        enter.setVisible(true);
        JPanel panel = new JPanel();
        window.add(panel);
        panel.add(enter);
        window.setVisible(true);

    }

}       

您需要在您的JFrame中添加一个JPanel。然后您可以将您的JButton添加到JPanel .