/**
* 控制面板类,继承自JPanel.
* 上边安放预显窗口、等级、得分、控制按钮
* 主要用来控制游戏进程。
*/
class ControlPanel extends JPanel {
private JTextField
tfLevel = new JTextField("" + ErsBlocksGame.DEFAULT_LEVEL),
tfScore = new JTextField("0");
private JButton
btPlay = new JButton("Play"),
btPause = new JButton("Pause"),
btStop = new JButton("Stop"),
btTurnLevelUp = new JButton("Turn hard"),
btTurnLevelDown = new JButton("Turn easy");
private JPanel plTip = new JPanel(new BorderLayout());
private TipPanel plTipBlock = new TipPanel();
private JPanel plInfo = new JPanel(new GridLayout(4, 1));
private JPanel plButton = new JPanel(new GridLayout(5, 1));
private Timer timer;
private ErsBlocksGame game;
private Border border = new EtchedBorder(
EtchedBorder.RAISED, Color.white, new Color(148, 145, 140));