为什么我的JFrame不抽奖？

Question

I am trying to draw to my JFrame with Graphics. For some reason, it won't draw anything. What am I doing wrong? I have added my paint method, imported everything. Am I placing the method in the wrong place?

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;

public class Main extends Canvas implements MouseListener, KeyListener {

    public int WIDTH = 1080;
    public static Main main;
    public boolean playing = false;

    public Main() {
        addMouseListener(this);
        addKeyListener(this);

        JFrame frame = new JFrame("Clicker");
        frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

    public void paint(Graphics g) {
        g.setColor(Color.BLACK);
        g.fillRect(50, 50, 100, 100);
    }

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

    public void MainScreen() {

    }

    @
    Override
    public void keyPressed(KeyEvent e) {
        // TODO Auto-generated method stub

    }

    @
    Override
    public void keyReleased(KeyEvent e) {
        // TODO Auto-generated method stub

    }

    @
    Override
    public void keyTyped(KeyEvent e) {
        // TODO Auto-generated method stub

    }

    @
    Override
    public void mouseClicked(MouseEvent evt) {
        // TODO Auto-generated method stub

    }

    @
    Override
    public void mouseEntered(MouseEvent evt) {
        // TODO Auto-generated method stub

    }

    @
    Override
    public void mouseExited(MouseEvent evt) {
        // TODO Auto-generated method stub

    }

    @
    Override
    public void mousePressed(MouseEvent evt) {
        // TODO Auto-generated method stub

    }

    @
    Override
    public void mouseReleased(MouseEvent evt) {
        // TODO Auto-generated method stub

    }

}

Answer 1

Try to extend from the JFrame class instead of the Canvas class:

public class Main extends JFrame implements ...

You also have to edit your constructor then like:

public Main() {
    super("Clicker");

    addMouseListener(this);
    addKeyListener(this);

    setExtendedState(JFrame.MAXIMIZED_BOTH); 
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    setVisible(true);
}