public static final int FLAG_HOMEKEY_DISPATCHED = 0x80000000;    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        this.getWindow().setFlags(FLAG_HOMEKEY_DISPATCHED, FLAG_HOMEKEY_DISPATCHED);//关键代码        setContentView(R.layout.main);    }    再重写onKey事件就可以。