gamelistener.java

一个java的俄罗斯方块实现

package cs111.tetris.data;

/**
 * This interface can be implemented by anyone who wants
 * to be notified when the state of a Game instance changes.
 * <p>
 * The Game class provides an <code>addListener()</code> method 
 * to add listeners to a Game.
 * <p>
 * Typicaly a UI component implements the GameListener interface and calls
 * addListener to ask a Game to be notified of changes in the game
 * state. Thus, the GUI will know when it is necessary to update the 
 * visual display of the game state on the screen.
 * <p>
 * <b>CS111 info:</b> Using this kind of Listener notification mechanism 
 * is very typical for programs with a GUI. For example, you will find many different
 * listener interfaces also in the Java libraries.
 * <p>
 * This programming style allows us to decouple the game playing 
 * logic and interesting data structures from the
 * GUI code. And so... this allows us to provide you with all
 * of that messy GUI related code and leave the more interesting 
 * stuff to you!
 * 
 * @author kdvolder
 */
public interface GameListener {
	
	/**
     * This method is called by the game instance when the board state
	 * changed (so the UI should redraw the board on the screen).
	 */
	public void boardChanged();
	
	/**
	 * This is called when the pieceCount was updated (e.g. a
	 * new piece was entered at the top of the board).
	 */
	public void countChanged();
	
	/**
	 * This is called when the "gameOn" status changed. That
	 * is, the game is either started or stopped.
	 */
	public void gameOnChanged();

}