片段的还原instanceState包始终为空

Question

我正在试图保存我的回收视图的LinearLayoutManager状态。

Fragment.java :

@Override
    public void onSaveInstanceState(Bundle outState) {
        Log.i("frag", "onSaveInstanceState called");
        super.onSaveInstanceState(outState);
        outState.putParcelable("myState", mGridLayoutManager.onSaveInstanceState());
    }

@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
          if (savedInstanceState != null) {
                Log.i(MainActivity.TAG, "restore called from createView");
                mGridLayoutManager.onRestoreInstanceState(savedInstanceState.getParcelable("myState"));
            }
          .....
          ....
    }

但是savedInstanceState总是空的。

我已经尝试在onCreate &方法中恢复它的状态，但没有成功。我做错什么了？

我检查了这些问题，以确定这是保存和恢复的正确方法：

Recyclerview store / save state

Save recyclerview scroll position

Answer 1

尝试在调用super.onSaveInstanceState()之后调用outstate.putParcelable(Outstate)？

如果这不起作用，也许可以尝试将一个字符串放入包中，看看它是否与mGridLayoutManager.onSaveInstanceState()失败有关？