@Override
    protected void onSaveInstanceState(Bundle outState) { //Bundle对应onCreate方法中的Bundul对象
         super.onSaveInstanceState(outState);
         String tempData = "http://www.mamicode.com/Something you just typed";
         outState.putString("data_key", tempData);//
    }

 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    if (savedInstanceState != null) {    //如果存储的数据不是空的
        String tempData = http://www.mamicode.com/savedInstanceState.getString("data_key");   //调savedInstanceState的getString()方法就可以调出数据
        Log.d(“MainActivity”, tempData);
    }
}