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()
并在中还原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()
和恢复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。