public void onSaveInstanceState(Bundle outState) {
        Parcel outParcel = Parcel.obtain();
        outParcel.writeSparseBooleanArray(mCheckStates);
        final int numStates = mCheckedIdStates.size();
        outParcel.writeInt(numStates);
        for (int i=0; i<numStates; i++) {
            outParcel.writeLong(mCheckedIdStates.keyAt(i));
            outParcel.writeInt(mCheckedIdStates.valueAt(i));
        }
        byte[] states = outParcel.marshall();
        outState.putByteArray(SELECTED_ITEMS_KEY, states);
        outParcel.recycle();
    }
Returns the checked state of the specified position. The result is only
valid if the choice mode has been set to AbsListView.CHOICE_MODE_SINGLE,
but the code does not check this.

@param position The item whose checked state to return
@return The item's checked state
@see #setChoiceMode(int)
app/src/main/java/com/example/android/sunshine/app/ItemChoiceManager.java