为什么没有显示呢？

[quaitong]

刚才写了一段小程序，但是不知道为什么不能显示“loading....”
大牛帮忙指点一下哈。。。

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;


public class WarningFrame extends JFrame{
	
	JLabel label = new JLabel();
	JPanel contentPane = (JPanel) getContentPane();
	
	public static void main(String[] args){
		WarningFrame f = new WarningFrame("loading....");
		
	}
	
	public WarningFrame(String warning){
		
		this.setTitle("-_-");
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.setResizable(false);
		this.setSize(188,100);
		this.setLocation(500,0);
		
		label.setText(warning);
		contentPane = (JPanel) getContentPane();
		contentPane.setLayout(null);
		contentPane.add(label);
		contentPane.setVisible(true);
		this.toFront();
		this.setVisible(true);
		
	}
}

[dracularking]

要有layout的 随便设个

contentPane.setLayout(new FlowLayout());

[quaitong]

啊哦，这样啊，谢谢

[lvzhu18]

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class WarningFrame {
    public static void main(String[] args) {
        
        WarningFrames frame = new WarningFrames();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);        
    }

}

class WarningFrames extends JFrame {
    public WarningFrames() {
        setTitle("Warning");
        setSize(300, 200);
        
        JPanel contentPanel = new JPanel();
        JLabel label = new JLabel("Loading...");
        contentPanel.add(label);
        add(contentPanel);
    }
}