Problem with KeyListener and jframe

I've got problem with JFrame and KeyListerner in Tetris game. I've got two frames - one with Start Button and second with Board. In the second frame I want to control shapes from keyboard, but when I click start I can't do that. When I disactivate first frame - everything is ok. I know I have to focus on second frame and I tried do that, but with no effect. Could someone help me? First frame:

package tetris;

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

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


public class Tetris implements ActionListener {
public Tetris() {
initComponents();
}
Component contentPane;
JLabel statusbar  = new JLabel(" 0"); 
JLabel name  = new JLabel("Tetris"); 
JButton startbut = new JButton("Start");
JFrame window = new JFrame();
JPanel panelStart = new JPanel();
JPanel game = new JPanel();
int nameSize=24;
Font fontName = new Font("Dialog", Font.BOLD, nameSize);
BorderLayout borderLayout = new BorderLayout();
Board board = new Board(this);

public void initComponents() {
    window.setBounds(500,200,200,400);
    window.setTitle("Tetris");
    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window.setVisible(true);

    window.add(panelStart);
    window.add(game);
    panelStart.setLayout (null);
    panelStart.setVisible(true);
    window.setContentPane(panelStart);

    name.setSize(70,25);
    name.setLocation(53,10);
    name.setFont(fontName);
    panelStart.add(name);
    startbut.setSize(70,25);
    startbut.setLocation(50,80);
    panelStart.add(startbut);
    startbut.addActionListener(this);
  }

public void initGame() {

    game.setLayout (borderLayout);
    panelStart.setVisible(false);
    window.remove(panelStart);

    game.setVisible(true);
    window.setContentPane(game);




    game.setFocusable(true);
    statusbar = new JLabel(" 0");
   game.add(statusbar, BorderLayout.SOUTH);
     game.add(board);
   board.start();

 }
 public JLabel getStatusBar() {
   return statusbar;
 }
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(e.getSource() == startbut)
{
    initGame();

}
}


}

Board code:

package tetris;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;


import tetris.Shape.Tetrominoes;


public class Board extends JPanel implements ActionListener      {


    final int BoardWidth = 10;
    final int BoardHeight = 22;

    Timer timer;
    boolean isFallingFinished = false;
    boolean isStarted = false;
    boolean isPaused = false;
    int numLinesRemoved = 0;
    int curX = 0;
    int curY = 0;
    JLabel statusbar;
    Shape curPiece;
    Tetrominoes[] board;



    public Board(Tetris parent) {


    //   setFocusable(true);
       curPiece = new Shape();
       timer = new Timer(400, this);
       timer.start(); 

       statusbar =  parent.getStatusBar();
       board = new Tetrominoes[BoardWidth * BoardHeight];
       KeyListener keyListener = new TAdapter();
       addKeyListener(keyListener);
       repaint();
       clearBoard();  

    }

    public void actionPerformed(ActionEvent e) {
        if (isFallingFinished) {
            isFallingFinished = false;
            newPiece();
        } else {
            oneLineDown();
        }
    }


    int squareWidth() { return (int) getSize().getWidth() / BoardWidth; }
    int squareHeight() { return (int) getSize().getHeight() / BoardHeight; }
    Tetrominoes shapeAt(int x, int y) { return board[(y * BoardWidth) + x]; }


    public void start()
    {
        if (isPaused)
            return;

        isStarted = true;
        isFallingFinished = false;
        numLinesRemoved = 0;
        clearBoard();

        newPiece();
        timer.start();
    }

    private void pause()
    {
        if (!isStarted)
            return;

        isPaused = !isPaused;
        if (isPaused) {
            timer.stop();
            statusbar.setText("paused");
        } else {
            timer.start();
            statusbar.setText(String.valueOf(numLinesRemoved));
        }
        repaint();
    }

    public void paint(Graphics g)
    { 
        super.paint(g);

        Dimension size = getSize();
        int boardTop = (int) size.getHeight() - BoardHeight * squareHeight();


        for (int i = 0; i < BoardHeight; ++i) {
            for (int j = 0; j < BoardWidth; ++j) {
                Tetrominoes shape = shapeAt(j, BoardHeight - i - 1);
                if (shape != Tetrominoes.NoShape)
                    drawSquare(g, 0 + j * squareWidth(),
                               boardTop + i * squareHeight(), shape);
            }
        }

        if (curPiece.getShape() != Tetrominoes.NoShape) {
            for (int i = 0; i < 4; ++i) {
                int x = curX + curPiece.x(i);
                int y = curY - curPiece.y(i);
                drawSquare(g, 0 + x * squareWidth(),
                           boardTop + (BoardHeight - y - 1) * squareHeight(),
                           curPiece.getShape());
            }
        }
    }

    private void dropDown()
    {
        int newY = curY;
        while (newY > 0) {
            if (!tryMove(curPiece, curX, newY - 1))
                break;
            --newY;
        }
        pieceDropped();
    }

    private void oneLineDown()
    {
        if (!tryMove(curPiece, curX, curY - 1))
            pieceDropped();
    }


    private void clearBoard()
    {
        for (int i = 0; i < BoardHeight * BoardWidth; ++i)
            board[i] = Tetrominoes.NoShape;
    }

    private void pieceDropped()
    {
        for (int i = 0; i < 4; ++i) {
            int x = curX + curPiece.x(i);
            int y = curY - curPiece.y(i);
            board[(y * BoardWidth) + x] = curPiece.getShape();
        }

        removeFullLines();

        if (!isFallingFinished)
            newPiece();
    }

    private void newPiece()
    {
        curPiece.setRandomShape();
        curX = BoardWidth / 2 + 1;
        curY = BoardHeight - 1 + curPiece.minY();

        if (!tryMove(curPiece, curX, curY)) {
            curPiece.setShape(Tetrominoes.NoShape);
            timer.stop();
            isStarted = false;
            statusbar.setText("game over");
        }
    }

    private boolean tryMove(Shape newPiece, int newX, int newY)
    {
        for (int i = 0; i < 4; ++i) {
            int x = newX + newPiece.x(i);
            int y = newY - newPiece.y(i);
            if (x < 0 || x >= BoardWidth || y < 0 || y >= BoardHeight)
                return false;
            if (shapeAt(x, y) != Tetrominoes.NoShape)
                return false;
        }

        curPiece = newPiece;
        curX = newX;
        curY = newY;
        repaint();
        return true;
    }

    private void removeFullLines()
    {
        int numFullLines = 0;

        for (int i = BoardHeight - 1; i >= 0; --i) {
            boolean lineIsFull = true;

            for (int j = 0; j < BoardWidth; ++j) {
                if (shapeAt(j, i) == Tetrominoes.NoShape) {
                    lineIsFull = false;
                    break;
                }
            }

            if (lineIsFull) {
                ++numFullLines;
                for (int k = i; k < BoardHeight - 1; ++k) {
                    for (int j = 0; j < BoardWidth; ++j)
                         board[(k * BoardWidth) + j] = shapeAt(j, k + 1);
                }
            }
        }

        if (numFullLines > 0) {
            numLinesRemoved += numFullLines;
            statusbar.setText(String.valueOf(numLinesRemoved));
 开发者_如何学C           isFallingFinished = true;
            curPiece.setShape(Tetrominoes.NoShape);
            repaint();
        }
     }

    private void drawSquare(Graphics g, int x, int y, Tetrominoes shape)
    {
        Color colors[] = { new Color(0, 0, 0), new Color(204, 102, 102), 
            new Color(102, 204, 102), new Color(102, 102, 204), 
            new Color(204, 204, 102), new Color(204, 102, 204), 
            new Color(102, 204, 204), new Color(218, 170, 0)
        };


        Color color = colors[shape.ordinal()];

        g.setColor(color);
        g.fillRect(x + 1, y + 1, squareWidth() - 2, squareHeight() - 2);

        g.setColor(color.brighter());
        g.drawLine(x, y + squareHeight() - 1, x, y);
        g.drawLine(x, y, x + squareWidth() - 1, y);

        g.setColor(color.darker());
        g.drawLine(x + 1, y + squareHeight() - 1,
                         x + squareWidth() - 1, y + squareHeight() - 1);
        g.drawLine(x + squareWidth() - 1, y + squareHeight() - 1,
                         x + squareWidth() - 1, y + 1);

    }
    public boolean isFocusable() {
        return true;
    }
  public class TAdapter implements KeyListener  {
          public void keyTyped(KeyEvent e) {
          }
         public void keyPressed(KeyEvent e) {
             if (!isStarted || curPiece.getShape() == Tetrominoes.NoShape) {  
                 return;
             }

             int keycode = e.getKeyCode();

             if (keycode == 'p' || keycode == 'P') {
                 pause();
                 return;
             }

             if (isPaused)
                 return;

             switch (keycode) {
             case KeyEvent.VK_LEFT:
                 tryMove(curPiece, curX - 1, curY);
                 break;
             case KeyEvent.VK_RIGHT:
                 tryMove(curPiece, curX + 1, curY);
                 break;
             case KeyEvent.VK_DOWN:
                 tryMove(curPiece.rotateRight(), curX, curY);
                 break;
             case KeyEvent.VK_UP:
                 tryMove(curPiece.rotateLeft(), curX, curY);
                 break;
             case KeyEvent.VK_SPACE:
                 dropDown();
                 break;
             case 'd':
                 oneLineDown();
                 break;
             case 'D':
                 oneLineDown();
                 break;
             }

         }
        @Override
        public void keyReleased(KeyEvent arg0) {
            // TODO Auto-generated method stub

        }
     }
}

Your code is to large for me to want to dig through, but what you want to do is possible.

Either way, I would suggest you move to one frame and possibly use a CardLayout or another GUI item to hide and show components because having the user change screens when the game starts is a strange UI. It will be more user friendly to just have it all in one frame. And this might fix your current issue.

Same here, the code is too large to dig. However if you are facing problems in setting the focus try frame.requestFocus();

First, a JPanel that wants to grab focus has to be focusable or focus traversable. You should consider overriding isFocusTraversable to return true.

In your panel class :

@Override
public boolean isFocusTraversable()
{
  return true;
}//met

This means your component can have focus.

Second, if you want your jpanel to* actually have the focus*, you can call his method

panel.requestFocus();

you should do that at the beginning of the game, right after the pack/setVisible( true ); and at the end of every actionlistener that will make it loose focus (typically buttons'actionlisteners).

Regards, Stéphane

Instead of using a KeyListener you should be using Key Bindings.

keyListener was not working for me in Frame. Later I found out that the problem was that my key controls were going to the Button that I had added in the Frame. When I removed the Button, The key control went back to the frame and keyEvents were working. But I have not found a way to use keyEvents even after keeping the Button in Frame!