如何正确将片段的实例状态保存在后堆栈中？

要正确保存实例状态，Fragment请执行以下操作：

1.在片段中，通过覆盖保存实例状态

onSaveInstanceState()

onActivityCreated()

class MyFragment extends Fragment {    @Override    public void onActivityCreated(Bundle savedInstanceState) {        super.onActivityCreated(savedInstanceState);        ...        if (savedInstanceState != null) { //Restore the fragment's state here        }    }    ...    @Override    public void onSaveInstanceState(Bundle outState) {        super.onSaveInstanceState(outState);        //Save the fragment's state here    }}

2.而且很重要的一点，在活动中，你必须保存片段的实例在

onSaveInstanceState()

onCreate()

class MyActivity extends Activity {    private MyFragment     public void onCreate(Bundle savedInstanceState) {        ...        if (savedInstanceState != null) { //Restore the fragment's instance mMyFragment = getSupportFragmentManager().getFragment(savedInstanceState, "myFragmentName"); ...        }        ...    }    @Override    protected void onSaveInstanceState(Bundle outState) {        super.onSaveInstanceState(outState);        //Save the fragment's instance        getSupportFragmentManager().putFragment(outState, "myFragmentName", mMyFragment);    }}

希望这可以帮助。