关于J2ME游戏切换屏幕的问题，求大虾指导~
请问怎么切换屏幕？为什么我的代码不起作用呢？贴代码

public void commandAction(Command c, Displayable d) {

		if(c==cmdbk){

			System.out.println("huiqu22");

			game_state=GAME_STATE_GAMING;

			System.out.println(cmdbk);

			System.out.println("qwqwqwwq");

			

		}else if(c==cmdok){			

			System.out.println("qwqdffdfd");

			game_state=GAME_STATE_MENU;

			

			System.out.println("huiqu");

		}else if(c==backCommand){

			game_state=GAME_STATE_GAMING;

		}

		

	}

下面是主循环

public void run() {

		while(!bQuit){

			//if(flag==true){

			offg.setColor(255,255,255);

			offg.fillRect(0,0,getWidth(),getHeight());

			repaint();

			input();

			 try {

				Thread.currentThread();

				Thread.sleep(80);

			} catch (InterruptedException e) {

				

				e.printStackTrace();

			} 

		}

	}

input函数

public void input(){

		int k=this.getKeyStates();

		switch (game_state) {

		case GAME_STATE_INIT:			

			paintINIT();

			break;

		case GAME_STATE_LOGO:

			paintLOGO();

			break;

		case GAME_STATE_MENU:

			paintMeun();

		break;

		case GAME_STATE_GAMING:			

			switch (game) {

			case GAMING:

				lm.paint(offg,0, 0);

				//检测边界碰撞

				checkBound();

				//检测精灵之间的碰撞

				iscollision();

				//检测Sprite方向

				checkDir(k);

				break;

			}

			case DEP_HR:

				//game_state=GAME_STATE_LOGO;

			break;

		case GAME_STATE_ROLE:

			rolefrm.append(cg);

			rolefrm.addCommand(cmdbk);

			rolefrm.addCommand(cmdok);

			//frm.setCommandListener(this);

			this.m4.dis.setCurrent(rolefrm);

			break;

		case GAME_STATE_HELP:

			paintHelp(offg);



这里有点问题，求指教			break;

		case GAME_STATE_EXIT:			

			exit();			

			break;

		default:

			break;

		}

	}

------解决方案--------------------
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