[aaaman]

Hi, im trying to create a cheap version of a tetris game where i wanna use the keyboard instead of having buttons to do all the functions (left, right,roate,drop) and i need help as do how can i implement keyListener as it is really confusing.

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

/**
* A ButtonsPanel contains "left", "right", "rotate" and "drop" buttons for
* controlling a Game.
*
* @author Ryan Heise
*/
public class ButtonsPanel extends JPanel implements ActionListener //TextListener

{
/**
* The Game to control.
*/
private Game game;

/**
* The left button.
*/
private JButton leftButton;

/**
* The right button.
*/
private JButton rightButton;

/**
* The rotate button.
*/
private JButton rotateButton;

/**
* The drop button.
*/
private JButton dropButton;

/**
* Constructs a new ButtonsPanel for controlling the given Game.
*
* @param game the Game to control.
*/
public ButtonsPanel(Game game)
{
this.game = game;

setLayout(new GridLayout(0,2));

leftButton = new JButton("Left");
leftButton.addActionListener(this);
// leftButton.addKeyListener(this);
add(leftButton);

rightButton = new JButton("Right");
rightButton.addActionListener(this);
//rightButton.addKeyListener(this);
add(rightButton);

rotateButton = new JButton("Rotate");
rotateButton.addActionListener(this);
// rotateButton.addActionListener(this);
add(rotateButton);

dropButton = new JButton("Drop");
// dropButton.addKeyListener(this);
dropButton.addActionListener(this);
add(dropButton);
}
public void actionPerformed(ActionEvent event)
{
if (event.getSource() == leftButton)
game.moveLeft();

if (event.getSource() == rightButton)
game.moveRight();

if (event.getSource() == rotateButton)
game.rotate();

if (event.getSource() == dropButton)
game.drop();
}
// public interface keyPressed(Keyevent event)
// {

// if (event.getInputMap().put(KeyStroke.getKeyStroke("VK_LEFT"),"pressed"))
// game.moveLeft();

// if (event.getInputMap().put(keyStroke.getKeyStroke("VK_RIGHT","pressed"))
// game.moveRight();

// if (event.getInputMap().put(keyStroke.getKeyStroke("VK_DOWN","pressed"))
// game.moveDrop();

// if (event.getInputMap().put(keyStroke.getKeyStroke("VK_UP","pressed"))
// game.moveRotate();

// }
}

Anyone got any ideas to change it?

[bpmurray]

First, you must make your class able to receive keyboard messages. This can only happen when it has focus, so you need to add this.setFocusable(true); to your constructor.

Now, you also need to be a keylistener, so you need to "implement" KeyListener. I'm unclear as to why you need the buttons on the panel, but you can make the entire panel react to the keyboard. Of course, this means you have to have the Keypressed/released/typed methods. Something like:

public class ButtonsPanel extends JPanel implements ActionListener, KeyListener

{
	/**
	 * The Game to control.
	 */
	private Game game;

	/**
	 * The left button.
	 */
	private JButton leftButton;

	/**
	 * The right button.
	 */
	private JButton rightButton;

	/**
	 * The rotate button.
	 */
	private JButton rotateButton;

	/**
	 * The drop button.
	 */
	private JButton dropButton;

	/**
	 * Constructs a new ButtonsPanel for controlling the given Game.
	 * 
	 * @param game
	 *            the Game to control.
	 */
	public ButtonsPanel(Game game) {
		this.game = game;
		this.setFocusable(true);

		setLayout(new GridLayout(0, 2));
		this.addKeyListener(this);
		
		leftButton = new JButton("Left");
		leftButton.addActionListener(this);
		leftButton.addKeyListener(this);
		add(leftButton);

		rightButton = new JButton("Right");
		rightButton.addActionListener(this);
		rightButton.addKeyListener(this);
		add(rightButton);

		rotateButton = new JButton("Rotate");
		rotateButton.addActionListener(this);
		rotateButton.addActionListener(this);
		add(rotateButton);

		dropButton = new JButton("Drop");
		dropButton.addKeyListener(this);
		dropButton.addActionListener(this);
		add(dropButton);
	}

	public void actionPerformed(ActionEvent event) {
		if (event.getSource() == leftButton)
			game.moveLeft();

		if (event.getSource() == rightButton)
			game.moveRight();

		if (event.getSource() == rotateButton)
			game.rotate();

		if (event.getSource() == dropButton)
			game.drop();
	}
	
	public void keyPressed(KeyEvent e) {
		int key = e.getKeyCode();
		if(key == KeyEvent.VK_LEFT)
			game.moveLeft();
		if(key == KeyEvent.VK_RIGHT)
			game.moveRight();
		if(key == KeyEvent.VK_UP)
			game.rotate();
		if(key == KeyEvent.VK_DOWN)
			game.drop();
	}
	public void keyTyped(KeyEvent e) {}
	
	
	// public interface keyPressed(Keyevent event)
	// {

	// if (event.getInputMap().put(KeyStroke.getKeyStroke("VK_LEFT"),"pressed"))
	// game.moveLeft();

	// if (event.getInputMap().put(keyStroke.getKeyStroke("VK_RIGHT","pressed"))
	// game.moveRight();

	// if (event.getInputMap().put(keyStroke.getKeyStroke("VK_DOWN","pressed"))
	// game.moveDrop();

	// if (event.getInputMap().put(keyStroke.getKeyStroke("VK_UP","pressed"))
	// game.moveRotate();

	// }
}

In the appropriate key method you should process the event, something like

[aaaman]

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

/**
* A ButtonsPanel contains "left", "right", "rotate" and "drop" buttons for
* controlling a Game.
*
* @author Ryan Heise
*/
public class ButtonsPanel extends JPanel implements ActionListener, KeyListener
{
/**
* The Game to control.
*/
private Game game;

/**
* The left button.
*/
private JButton leftButton;

/**
* The right button.
*/
private JButton rightButton;

/**
* The rotate button.
*/
private JButton rotateButton;

/**
* The drop button.
*/
private JButton dropButton;

/**
* Constructs a new ButtonsPanel for controlling the given Game.
*
* @param game the Game to control.
*/
public ButtonsPanel(Game game)
{
this.game = game;
this.addKeyListener(this);


setLayout(new GridLayout(0,2));

leftButton = new JButton("Left");
leftButton.addActionListener(this);
leftButton.addKeyListener(this);
add(leftButton);

rightButton = new JButton("Right");
rightButton.addActionListener(this);
rightButton.addKeyListener(this);
add(rightButton);

rotateButton = new JButton("Rotate");
rotateButton.addActionListener(this);
rotateButton.addKeyListener(this);
add(rotateButton);

dropButton = new JButton("Drop");
dropButton.addActionListener(this);
dropButton.addKeyListener(this);
add(dropButton);
}


public void actionPerformed(ActionEvent event)
{
if (event.getSource() == leftButton)
game.moveLeft();

if (event.getSource() == rightButton)
game.moveRight();

if (event.getSource() == rotateButton)
game.rotate();

if (event.getSource() == dropButton)
game.drop();
}

public void keyPressed(KeyEvent event) {
int key = event.getKeyCode();

if(key == KeyEvent.VK_LEFT)
game.moveLeft();

if(key == KeyEvent.VK_RIGHT)
game.moveRight();

if(key == KeyEvent.VK_UP)
game.rotate();

if(key == KeyEvent.VK_DOWN)
game.drop();

public void keyTyped(KeyEvent event){}

}
}


ok ive changed it however public void keyTyped(KeyEvent event){} is a illegal expression and i cant get it to be working

[bpmurray]

What development system are you using? Do you see any other error marks before the illegal expression error? I can see the typo straight away: there's a misplaced closing brace "}" - if you can't find this, you shouldn't be trying to write this app!

[aaaman]

ah i use blueJ its the ****test thing ever and i cbf getting netbeans, i fixed to problem i forgot to place all three methods, thanks alot pal for ya help