How do I use Key Listener to close a panel?

2018-01-11 21:06 Michael Gonzalez imported from Stackoverflow

I am trying to get my load frame to close when the enter key is pushed. Can anyone help. I wanted to put an if statement in my constructor this if statement does get accessed however it does not work. I read something about repainting and validating however not sure if I implementing this correctly. I just want the load panel to close and then display the game panel. A more direct question would be why is the if (enter == true) not being accessed when I push enter. The enter variable does get updated on key press but the if statement does not activate. Why?

public class GameFrame implements KeyListener {

     boolean enter = false;
     boolean focus = true;


    public GameFrame() {

        Game game = new Game();//constructor of game instane
        game.setFocusable(focus);

        JFrame frame = new JFrame(); // constructor of JF instance
        frame.setBounds(0, 0, Game.HEIGHT, Game.WIDTH);
        frame.setTitle(Game.TITLE);

        LoadingPanel load = new LoadingPanel();
        load.setSize(Game.WIDTH - 40, Game.HEIGHT - 40);
        load.setLocation(20, 20);
        load.setVisible(true);
        load.addKeyListener(this);      
        load.setFocusable(focus);
        frame.add(load);



        frame.add(game);
        frame.setResizable(false);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocationRelativeTo(null);

        game.setVisible(true);
        frame.setVisible(true);

        if (enter == true){
            System.out.println("xx");//test for access
           frame.remove(load);
           frame.validate();
          frame.repaint();

        }
        game.start();

    }

    @Override
    public void keyTyped(KeyEvent e) {

    }

    @Override
    public void keyPressed(KeyEvent e) {
        if (e.getKeyCode() == KeyEvent.VK_ENTER) {

            this.enter = true;

            this.focus = true;//setting to true just in case
            System.out.println("GameFrame pressed");
            System.out.println("enter is " + this.enter);

        }
    }
    @Override
    public void keyReleased(KeyEvent e) {

    }
}

Thanks in advance for any help.

UPDATE: The following code used Keybinding and it works perfect.

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;

public class GameFrame {

    LoadingPanel load;

    public GameFrame() {

        Game game = new Game();//constructor of game instance

        JFrame frame = new JFrame(); // constructor of JF instance
        frame.setBounds(0, 0, Game.HEIGHT, Game.WIDTH);
        frame.setTitle(Game.TITLE);

        load = new LoadingPanel();
        load.setSize(Game.WIDTH - 40, Game.HEIGHT - 40);
        load.setLocation(20, 20);
        load.setVisible(true);

        frame.add(load);

        frame.add(game);
        frame.setResizable(false);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocationRelativeTo(null);

        game.setVisible(true);
        frame.setVisible(true);

        game.start();

        InputMap im = load.getInputMap(JPanel.WHEN_IN_FOCUSED_WINDOW);
        ActionMap am = load.getActionMap();

        im.put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER, 0), "Enter");
        am.put("Enter", new AbstractAction() {
            @Override
            public void actionPerformed(ActionEvent e) {

                frame.remove(load);

            }
        });
    }
}

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Source code

public class MainWindow extends JFrame {

private JPanel contentPane;
private JPanel pnLateralPanel;
private JButton btnCreateParty;
private MyButtonTransitionAnimation buttonColorTransition = new MyButtonTransitionAnimation();
private JButton btnJoinParty;
private Color x,y;
private JPanel pnIluminationLateralCreateParty;
private JPanel pnIluminationLateralJoinParty;
private JLabel lblMainMenu;
private JLabel lblLoginregister;
private JPanel pnIluminationLateralMyParties;
private JButton btnMypartiesCart;
private JLabel lblGeneralOptions;
private JButton btnProfile;
private JButton btnSettings;
private JButton btnHelp;
private JLabel lblAbout;
private JPanel pnIluminationLateralProfile;
private JPanel pnIluminationLateralSettings;
private JPanel pnIluminationLateralHelp;

/**
 * Launch the application.
 */
public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
            try {
                MainWindow frame = new MainWindow();
                frame.setLocationRelativeTo(null);
                frame.setResizable(false);
                frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

/**
 * Create the frame.
 */
private class MyButtonTransitionAnimation extends MouseAdapter{


        @Override
        public void mouseEntered(MouseEvent arg0) {
            JButton buttonSource = (JButton) arg0.getSource();
            ArrayList<Color> colorsForButton = interpolateColors(x, y);
            ArrayList<Color> colorsForLateral = interpolateColors(x.brighter(), y.brighter());
            JPanel lateralPanel = (JPanel) pnLateralPanel.getComponentAt(0, buttonSource.getY());

            Thread th = new Thread() { //Ask about this syntax, we are extending Thread and making a custom run?
                public void run() {
                    try {
                        for (int i = 0; i < colorsForButton.size(); i++) {
//                              if(!isMouseInsideComponent(buttonSource))
//                                  break;
                            Thread.sleep(5);
                            buttonSource.setBackground(colorsForButton.get(i));
                            lateralPanel.setBackground(colorsForLateral.get(i));
                        }
//                          if(isMouseInsideComponent(buttonSource))
                            buttonSource.setBackground(y);
                            lateralPanel.setBackground(colorsForLateral.get(colorsForLateral.size() - 1));
//                          else
//                              buttonSource.setBackground(x);

                    }
                    catch(Exception e ) {
                        e.printStackTrace();
                    }
                }
            };th.start();                   
        }

        public void mouseExited(MouseEvent arg0) {
            JButton buttonSource = (JButton) arg0.getSource();
            ArrayList<Color> colorsForButton = interpolateColors(x, y);
            ArrayList<Color> colorsForLateral = interpolateColors(x, y.brighter());
            JPanel lateralPanel = (JPanel) pnLateralPanel.getComponentAt(0, buttonSource.getY());


            Thread th = new Thread() {
                public void run() {
                    try {
                        for (int i = colorsForButton.size() - 1; i >= 0; i--) {
//                              if(!isMouseInsideComponent(buttonSource)) {
//                                  break;
//                              }
                            Thread.sleep(5);
                            buttonSource.setBackground(colorsForButton.get(i));
                            lateralPanel.setBackground(colorsForLateral.get(i));

                        }
                        buttonSource.setBackground(x);
                        lateralPanel.setBackground(buttonSource.getBackground());
                    }
                    catch(Exception e ) {
                        e.printStackTrace();
                    }
                }
            };th.start();   
        }
    }

private boolean isMouseInsideComponent(Component c) {
    Point mousePos = MouseInfo.getPointerInfo().getLocation();
    Rectangle bounds = c.getBounds();
    bounds.setLocation(c.getLocationOnScreen());
    return bounds.contains(mousePos);
}


public MainWindow() {
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
    setBounds(0, 0, (int) Math.round(screenSize.width * 0.6), (int) Math.round(screenSize.height * 0.6));
    contentPane = new JPanel();
    contentPane.setForeground(new Color(230, 230, 250));
    contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
    setContentPane(contentPane);
    contentPane.setLayout(null);
    contentPane.add(getPnLateralPanel());
    UIManager.put("Button.select", pnLateralPanel.getBackground()); // How to do this without modifiying the whole UI (do this just for specific buttons)

    x = pnLateralPanel.getBackground();
    y = pnLateralPanel.getBackground().brighter();
}

private JPanel getPnLateralPanel() {
    if (pnLateralPanel == null) {
        pnLateralPanel = new JPanel();
        pnLateralPanel.setBackground(new Color(125, 56, 101));
        pnLateralPanel.setBounds(0, 0, 324, 601);
        pnLateralPanel.setLayout(null);
        pnLateralPanel.add(getBtnCreateParty());
        pnLateralPanel.add(getBtnJoinParty());
        pnLateralPanel.add(getPnIluminationLateralCreateParty());
        pnLateralPanel.add(getPanel_1());
        pnLateralPanel.add(getLblMainMenu());
        pnLateralPanel.add(getLblLoginregister());
        pnLateralPanel.add(getPnIluminationLateralMyParties());
        pnLateralPanel.add(getBtnMypartiesCart());
        pnLateralPanel.add(getLblGeneralOptions());
        pnLateralPanel.add(getBtnProfile());
        pnLateralPanel.add(getBtnSettings());
        pnLateralPanel.add(getBtnHelp());
        pnLateralPanel.add(getLblAbout());
        pnLateralPanel.add(getPnIluminationLateralProfile());
        pnLateralPanel.add(getPnIluminationLateralSettings());
        pnLateralPanel.add(getPnIluminationLateralHelp());
    }
    return pnLateralPanel;
}

protected ArrayList<Color> interpolateColors(Color x, Color y) {
    ArrayList<Color> colors = new ArrayList<>();
    for (float i = 0; i < 0.99f; i += 0.01) {
        float blending = 0.0f + i;
        float inverse_blending = 1 - blending;

        float red = y.getRed() * blending + x.getRed() * inverse_blending;
        float green = y.getGreen() * blending + x.getGreen() * inverse_blending;
        float blue = y.getBlue() * blending + x.getBlue() * inverse_blending;
        colors.add(new Color(red / 255, green / 255, blue / 255));
    }
    return colors;
}

private JButton getBtnCreateParty() {
    if (btnCreateParty == null) {
        btnCreateParty = new JButton("Create Party");
        btnCreateParty.addMouseListener(buttonColorTransition);
        btnCreateParty.setForeground(new Color(193, 167, 176));
        btnCreateParty.setFont(new Font("Century Gothic", Font.BOLD, 17));
        btnCreateParty.setBackground(pnLateralPanel.getBackground());
        btnCreateParty.setBounds(6, 149, 318, 43);
        btnCreateParty.setBorder(null);
        btnCreateParty.setFocusPainted(false);
    }
    return btnCreateParty;
}
private JButton getBtnJoinParty() {
    if (btnJoinParty == null) {
        btnJoinParty = new JButton("Join Party");
        btnJoinParty.addMouseListener(buttonColorTransition);
        btnJoinParty.setForeground(new Color(193, 167, 176));
        btnJoinParty.setFont(new Font("Century Gothic", Font.BOLD, 17));
        btnJoinParty.setBackground(pnLateralPanel.getBackground());
        btnJoinParty.setBounds(6, 205, 318, 43);
        btnJoinParty.setBorder(null);
        btnJoinParty.setFocusPainted(false);
    }
    return btnJoinParty;
}


private JPanel getPnIluminationLateralCreateParty() {
    if (pnIluminationLateralCreateParty == null) {
        pnIluminationLateralCreateParty = new JPanel();
        pnIluminationLateralCreateParty.setBounds(0, 149, 6, 43);
        pnIluminationLateralCreateParty.setBackground(pnLateralPanel.getBackground());
    }
    return pnIluminationLateralCreateParty;
}
private JPanel getPanel_1() {
    if (pnIluminationLateralJoinParty == null) {
        pnIluminationLateralJoinParty = new JPanel();
        pnIluminationLateralJoinParty.setBounds(0, 205, 6, 43);
        pnIluminationLateralJoinParty.setBackground(pnLateralPanel.getBackground());
    }
    return pnIluminationLateralJoinParty;
}
private JLabel getLblMainMenu() {
    if (lblMainMenu == null) {
        lblMainMenu = new JLabel("Main Menu");
        lblMainMenu.setForeground(new Color(15, 162, 169)); // Another color option: new Color(248, 183, 3)
        lblMainMenu.setFont(new Font("Century Gothic", Font.BOLD, 17));
        lblMainMenu.setBackground(new Color(0, 0, 153));
        lblMainMenu.setBounds(24, 120, 126, 16);
    }
    return lblMainMenu;
}
private JLabel getLblLoginregister() {
    if (lblLoginregister == null) {
        lblLoginregister = new JLabel("Login/Register");
        lblLoginregister.setForeground(new Color(15, 162, 169));
        lblLoginregister.setFont(new Font("Century Gothic", Font.BOLD | Font.ITALIC, 15));
        lblLoginregister.setBounds(200, 36, 112, 25);
    }
    return lblLoginregister;
}

private JPanel getPnIluminationLateralMyParties() {
    if (pnIluminationLateralMyParties == null) {
        pnIluminationLateralMyParties = new JPanel();
        pnIluminationLateralMyParties.setBounds(0, 261, 6, 43);
        pnIluminationLateralMyParties.setBackground(pnLateralPanel.getBackground());
    }
    return pnIluminationLateralMyParties;
}
private JButton getBtnMypartiesCart() {
    if (btnMypartiesCart == null) {
        btnMypartiesCart = new JButton("MyParties/Cart");
        btnMypartiesCart.addMouseListener(buttonColorTransition);
        btnMypartiesCart.setForeground(new Color(193, 167, 176));
        btnMypartiesCart.setFont(new Font("Century Gothic", Font.BOLD, 17));
        btnMypartiesCart.setBackground(pnLateralPanel.getBackground());
        btnMypartiesCart.setBounds(6, 261, 318, 43);
        btnMypartiesCart.setBorder(null);
        btnMypartiesCart.setFocusPainted(false);
    }
    return btnMypartiesCart;
}
private JLabel getLblGeneralOptions() {
    if (lblGeneralOptions == null) {
        lblGeneralOptions = new JLabel("General Options");
        lblGeneralOptions.setForeground(new Color(15, 162, 169));
        lblGeneralOptions.setFont(new Font("Century Gothic", Font.BOLD, 17));
        lblGeneralOptions.setBounds(24, 336, 144, 25);
    }
    return lblGeneralOptions;
}
private JButton getBtnProfile() {
    if (btnProfile == null) {
        btnProfile = new JButton("Profile");
        btnProfile.addMouseListener(buttonColorTransition);
        btnProfile.setForeground(new Color(193, 167, 176));
        btnProfile.setFont(new Font("Century Gothic", Font.BOLD, 17));
        btnProfile.setBackground(pnLateralPanel.getBackground());
        btnProfile.setBounds(6, 374, 318, 43);
        btnProfile.setBorder(null);
        btnProfile.setFocusPainted(false);
    }
    return btnProfile;
}
private JButton getBtnSettings() {
    if (btnSettings == null) {
        btnSettings = new JButton("Settings");
        btnSettings.addMouseListener(buttonColorTransition);
        btnSettings.setForeground(new Color(193, 167, 176));
        btnSettings.setFont(new Font("Century Gothic", Font.BOLD, 17));
        btnSettings.setBackground(pnLateralPanel.getBackground());
        btnSettings.setBounds(6, 430, 318, 43);
        btnSettings.setBorder(null);
        btnSettings.setFocusPainted(false);
    }
    return btnSettings;
}
private JButton getBtnHelp() {
    if (btnHelp == null) {
        btnHelp = new JButton("Help");
        btnHelp.addMouseListener(buttonColorTransition);
        btnHelp.setForeground(new Color(193, 167, 176));
        btnHelp.setFont(new Font("Century Gothic", Font.BOLD, 17));
        btnHelp.setBackground(pnLateralPanel.getBackground());
        btnHelp.setBounds(6, 486, 318, 43);
        btnHelp.setBorder(null);
        btnHelp.setFocusPainted(false);
    }
    return btnHelp;
}
private JLabel getLblAbout() {
    if (lblAbout == null) {
        lblAbout = new JLabel("About");
        lblAbout.setForeground(new Color(15, 162, 169));
        lblAbout.setFont(new Font("Century Gothic", Font.PLAIN, 15));
        lblAbout.setHorizontalAlignment(SwingConstants.CENTER);
        lblAbout.setBounds(215, 563, 97, 25);
    }
    return lblAbout;
}
private JPanel getPnIluminationLateralProfile() {
    if (pnIluminationLateralProfile == null) {
        pnIluminationLateralProfile = new JPanel();
        pnIluminationLateralProfile.setBounds(0, 374, 6, 43);
        pnIluminationLateralProfile.setBackground(pnLateralPanel.getBackground());
    }
    return pnIluminationLateralProfile;
}
private JPanel getPnIluminationLateralSettings() {
    if (pnIluminationLateralSettings == null) {
        pnIluminationLateralSettings = new JPanel();
        pnIluminationLateralSettings.setBounds(0, 430, 6, 43);
        pnIluminationLateralSettings.setBackground(pnLateralPanel.getBackground());

    }
    return pnIluminationLateralSettings;
}
private JPanel getPnIluminationLateralHelp() {
    if (pnIluminationLateralHelp == null) {
        pnIluminationLateralHelp = new JPanel();
        pnIluminationLateralHelp.setBounds(0, 486, 6, 43);
        pnIluminationLateralHelp.setBackground(pnLateralPanel.getBackground());
    }
    return pnIluminationLateralHelp;
}

}

Java Draw Linear Equation Graph Inside JFrame

I have a school assignment for CompSci where we need to create a graph for linear equations. This graph should have the axes drawn, and it should have two lines that are drawn from two equations. I have the graph itself working correctly, but I can't seem to figure out how to set the coordinates of the lines right. Currently I am using the following code to create and send the coordinates to my graph:

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    //corresponds to the first coordinate
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    double y11 = lslope*x11-lb*50;

    //corresponds to the second coordinate
    double x21=1000;
    double y21 = lslope*x21-lb*50;

    //outputs the coordinates of the two points just for the user's conveinience
    m.println(""+x11+"\n"+y11+"\n"+x21+"\n"+y21);

    //wingraph is a JFrame
    wingraph graph = new wingraph("Graph");
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    graph.setSize(1000,1000);
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    //the second set of 4 numbers will be a second line, but to get the graph working I'm just focusing on using one set. The setCoords method just sets the value of 8 coordinates inside a JFrame class which paints the X and Y axis in black, and then paints two lines with the specified coordinates in red.
    graph.setCoords(x11, y11, x21, y21, 1000,1000,1000,1000);

    //displays the graph
    graph.setVisible(true);

By inverting the slope the user entered, I can get the line to work correctly, but only if lslope is equal to 1. How could I manipulate the integers correctly so that my graph is displayed well whether the slope has decimals, is any real number, or is positive or negative?

If it helps, the code for the JFrame I'm using is:

    public class wingraph extends JFrame{

        public wingraph(String title){
            super(title);
            setLayout(new FlowLayout());
        }
        double xCoord1 = 0, yCoord1 = 0, xCoord2 = 0, yCoord2 = 0, xCoord12 = 0, yCoord12 = 0, xCoord22 = 0, yCoord22 = 0;
        public void setCoords(double x1, double y1, double x2, double y2, double x12, double y12, double x22, double y22){
            xCoord1 = x1;
            yCoord1 = y1;
            xCoord2 = x2;
            yCoord2 = y2;
            xCoord12 = x12;
            yCoord12 = y12;
            xCoord22 = x22;
            yCoord22 = y22;
        }        
        public void paint(Graphics g){
            g.setColor(Color.WHITE);
            g.fillRect(0, 0, this.getWidth(), this.getHeight());
            g.setColor(Color.BLACK);
            g.drawLine(this.getWidth()/2, 0, this.getWidth()/2, this.getHeight());
            g.drawLine(0, this.getHeight()/2, this.getWidth(), this.getHeight()/2);
            g.drawString("0",this.getWidth()/2-10,this.getHeight()/2-5);
            g.setColor(Color.red);
            g.drawLine((int) xCoord1,(int) yCoord1,(int) xCoord2,(int) yCoord2);
            g.drawLine((int) xCoord12,(int) yCoord12,(int) xCoord22,(int) yCoord22);
        }
}

Any help is appreciated.

Edit

Examples of my code running is this:

https://ibb.co/mVGFff

https://ibb.co/iMwbmL

https://ibb.co/mD080f

https://ibb.co/ezNct0

These all have issues since I need them all to be centered on the axis and the correct format such as:

https://ibb.co/cWstY0

https://ibb.co/goi0D0

I apologize if this is still unclear, but I am new to Java and am not all that familiar with how to explain exactly what I want other than to graph 2 lines with the equation y = mx + b on a Cartesian plane.

Edit 2

If the user inputs 1 for the lslopeand 0 for b, I want the x and y variables to be:

    x11 = 0;
    y11 = 1000;
    x21 = 1000;
    y21 = 0;

If lslope = 2 and b = 5 I want the x and y variables to be:

    x11 = 0
    y11 = 745;
    x21 = 1000;
    y21 = 245;

If lslope = -1 and b = 10 I want the x and y variables to be:

    x11 = 0
    y11 = 240;
    x21 = 1000;
    y21 = 740;

onKeyListener / dispatchKeyEvent wrong behavior with Edittext and keyboard listener

I have an EditText where i implement a Listener to know when the backspace is down / up

But the listener has an weird behavior.

When i press and hold any key from softkeyboard, the Down and Up keys are called on sequence, but only when i release the key.

When i press and hold backspace, the up/down are called multiple times, even i still pressing the key.

I use Logs to check the behavior. See the code below :

    myEditText.setOnKeyListener { v, keyCode, event ->


        if (event.getKeyCode() == KeyEvent.KEYCODE_DEL) {

            if (event.action == KeyEvent.ACTION_UP) {
                Log.wtf("delete", "up")

            }

            if (event.action == KeyEvent.ACTION_DOWN) {
                Log.wtf("delete", "down")
            }


        } else {

            if (event.action == KeyEvent.ACTION_UP) {
                Log.wtf("another ", "up")

            }

            if (event.action == KeyEvent.ACTION_DOWN) {
                Log.wtf("another", "down")
            }

        }

        true

    }
}

The log when i press and hold backspace:

E/delete: down
E/delete: up
E/delete: down
E/delete: up
E/delete: down
E/delete: up
E/delete: down
E/delete: up

The log when i press another key and release

E/another: down
E/another: up

i get the same error when i override dispatchKeyEvent () from activity.

override fun dispatchKeyEvent(event: KeyEvent): Boolean {

    if (event.getKeyCode() == KeyEvent.KEYCODE_DEL) {

        if (event.action == KeyEvent.ACTION_UP) {
            Log.wtf("delete", "up")

        }

        if (event.action == KeyEvent.ACTION_DOWN) {
            Log.wtf("delete", "down")
        }


    } else {

        if (event.action == KeyEvent.ACTION_UP) {
            Log.wtf("another ", "up")

        }

        if (event.action == KeyEvent.ACTION_DOWN) {
            Log.wtf("another", "down")
        }

    }

    return true

}

Is this the correct behavior ? Shoudn't the events be triggered only when i press and relase the button ?

'<> is not abstract and does not override abstract method keyReleased' even though keyReleased is not used

I am receiving two errors whilst creating this class. The first appears at:

public class DisplayerDeluxe extends JPanel implements ActionListener, 
KeyListener{

The following compiler error is being shown: DisplayerDeluxe is not abstract and does not override abstract method keyReleased(java.awt.event.KeyEvent) in java.awt.event.KeyListener

The next error is shown here

public void startGame() {
        paintCurrent(0, 0);
        for(int i = 0; i < height; i++) {
            for(int j = 0; j < width; j++) {
                bRef[i][j].addKeyListener(new KeyListener() { //Error is shown here
                        @Override public void keyPressed(KeyEvent e) {
                            mazeBuilder.buildPath();
                            Grid grid = mazeBuilder.getGrid();
                            if(e.getKeyCode() == KeyEvent.VK_UP && getYPos() != 0
                            && !getCell(getXPos(), getYPos(), grid).hasNorth()) {
                                moveUp();
                            }
                            else if(e.getKeyCode() == KeyEvent.VK_DOWN && getYPos() != height - 1
                            && !getCell(getXPos(), getYPos(), grid).hasSouth()) {
                                moveDown();
                            }
                            else if(e.getKeyCode() == KeyEvent.VK_LEFT && getXPos() != 0
                            && !getCell(getXPos(), getYPos(), grid).hasWest()) {
                                moveLeft();
                            }
                            else if(e.getKeyCode() == KeyEvent.VK_RIGHT && getXPos() != width - 1
                            && !getCell(getXPos(), getYPos(), grid).hasEast()) {
                                moveRight();
                            }
                            else {
                                infoBox("Only arrow key input in a dirrection " +
                                    "not blocked by a wall is valid.", "Maze Game");
                            }
                        }
                    });
            }
        }
        infoBox("Welcome to the maze game! Navigate your way to the end by using the arrow keys!", "Maze Game");
    }

The error reads: <anonymous DisplayerDeluxe$1> is not abstract and does not override abstract method keyReleased(java.awt.event.KeyEvent) in java.awt.event.KeyListener

This is confusing me greatly because nowhere in my code do I include keyReleased() and keyPressed() has the @Override notation. Any insight into this would be greatly appreciated!

KeyListener Works at Random in JFrame

Every time I run my app, it's a flip of the coin whether or not the KeyListener will function. If it works, it will not have any problems at any point afterwards, but if it's not functioning at the start of the app, it will never run until the program is closed out and started again.

public ThreeDimChessRunner() {
    record = new ArrayList<Integer>();
    winner = Player.NONE;
    game = new ThreeDimBoard(0);
    addMouseListener(this);
    addKeyListener(this);
    setFocusable(true);

    tm.start();
    screenWidth = screenSize.width;
    screenHeight = screenSize.height;
}

public static void main(String[] args){
    screenSize = Toolkit.getDefaultToolkit().getScreenSize();
    ThreeDimChessRunner p = new ThreeDimChessRunner();
    JFrame frame = new JFrame("3D Chess");  
    frame.setExtendedState(Frame.MAXIMIZED_BOTH);
    frame.setUndecorated(true);

    frame.setVisible(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.add(p);
}

The class ThreeDimChessRunner extends JPanel and implements KeyListener, ActionListener, and MouseInputListener.

tm is a Timer object

screenSize is a Dimension object

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