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javaswingkeylistenerkeyevent

Cannot find variable e.getkeycode


I'm a beginning programmer using Java and I'm trying to make a game in which you toss a disc through a moving hoop. The disc has a constant downward force and can be moved upward using the up key; however, before I even added any collision detection I started getting an error saying that java compile couldn't find the variable e of KeyEvent. I looked everywhere online and I'm sure I've just made a dumb mistake but can somebody take a look at this please.

import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.KeyListener;
import java.awt.event.KeyEvent;
import javax.swing.JPanel;
import javax.swing.JFrame;
import java.util.Random;

@SuppressWarnings("serial")
public class DiscHoopToss extends JPanel{

    int x = 710;
    int y = 150;
    int xm = -3;
    int ym = 1;
    int xr = 2;
    Random rng = new Random();
    int r = rng.nextInt((220-20)+1)+20;

  public DiscHoopToss() {
    KeyListener listener = new KeyListener() {

        @Override
        public void keyTyped(KeyEvent e) {
        } 

        @Override
        public void keyPressed(KeyEvent e) {
        if (e.getKeyCode == KeyEvent.VK_UP) ym = -2;
        }

        @Override
        public void keyReleased(KeyEvent e) {
        if (e.getKeyCode == KeyEvent.VK_UP) ym = 1;
        }
    };
    setFocusable(true);
  }




  private void moveDisc() {
    x = x + xm;
    y = y + ym;

    if (y == 0) {
    y = 150;
    x = 710;
    }

    if (y == getHeight() - 20) {
    y = 150;
    x = 710;
    }

    if (r + xr < 0) xr = 2;
    if (r + xr >getHeight() - 55) xr = -2; 
    r = r + xr;
  }


  @Override
  public void paint (Graphics g) {
    super.paint(g);
    Graphics2D g2d = (Graphics2D) g;
    g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

    g2d.drawOval(50,r,25,55);

    g2d.fillOval(x, y, 50, 20);
  }
  public static void main (String[] args) throws InterruptedException {
    JFrame frame = new JFrame("Toss the disc into the hoop!");
    DiscHoopToss game = new DiscHoopToss();
    frame.add(game);    
    frame.setSize(750, 350);
    frame.setResizable(false);
    frame.setVisible(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        while(true) {
        game.moveDisc();
        game.repaint();
        Thread.sleep(10);
    }
  }
}

Solution

  • Function calls in Java require parentheses. You need to write

    e.getKeyCode()
    

    not just

    e.getKeyCode