监听不到Android 的 Home 键

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
if(keyCode==3)//HOME键码为3
{
HomeKeyNum+=1;
Log.i("gogler", "home key pressed time is: "+HomeKeyNum);
}
return super.onKeyDown(keyCode, event);
}

实验结果没有预期日志输出，把键码换成BACK键码4则可以监听到。

官方解释：

Key code constant: Home key. This key is handled by the framework and is never delivered to applications.