旋转后无法还原滚动位置(RecyclerView) [英] Can't restore scroll position after rotation (RecyclerView)
本文介绍了旋转后无法还原滚动位置(RecyclerView)的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
旋转后以及关闭应用程序并再次打开后,无法恢复RecyclerView的滚动位置.在第一种情况下,我可以在清单中使用android:configChanges
,但是重新打开应用程序后却无济于事.
这是我的代码.尝试恢复状态后,我看到一个没有列表的空白屏幕.
Can't restore the scroll posiotn of RecyclerView after rotation and after I close the app and open it again. In the first case I could use android:configChanges
in Manifest, but it doesn't help after I reopen the app.
Here is my code. After trying restore the state I see an empty screen without my list.
public class MainActivity extends AppCompatActivity implements IMainContract.View {
private final String BUNDLE_RECYCLER_LAYOUT = MainActivity.class.getSimpleName() + ".save.state.list";
private IMainContract.Presenter mainPresenter;
private MainAdapter adapter;
private LinearLayoutManager layoutManager;
private ImageView ivRefresh;
private ProgressBar progressBar;
private RecyclerView rvUsers;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ivRefresh = (ImageView) findViewById(R.id.ivRefresh);
progressBar = (ProgressBar) findViewById(R.id.progressBar);
rvUsers = (RecyclerView) findViewById(R.id.rvUsers);
layoutManager = new LinearLayoutManager(this);
rvUsers.setLayoutManager(layoutManager);
mainPresenter = new MainPresenter(Repository.getInstance(this), this);
adapter = new MainAdapter(new ArrayList<>(), this);
rvUsers.setAdapter(adapter);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
ivRefresh.setOnClickListener(v -> mainPresenter.onRefreshPressed());
if (savedInstanceState != null) {
Parcelable savedRecyclerLayoutState = savedInstanceState.getParcelable(BUNDLE_RECYCLER_LAYOUT);
layoutManager.onRestoreInstanceState(savedRecyclerLayoutState);
} else {
mainPresenter.subscribe();
}
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putParcelable(BUNDLE_RECYCLER_LAYOUT, layoutManager.onSaveInstanceState());
}
//...
}
推荐答案
您需要在stackoverflow上遵循此 answer .更改您的代码
You need to follow this answer on stackoverflow.Change your code
public class MainActivity extends AppCompatActivity {
private final String KEY_RECYCLER_STATE = "recycler_state";
private MainAdapter adapter;
private LinearLayoutManager layoutManager;
private ImageView ivRefresh;
private ProgressBar progressBar;
private RecyclerView rvUsers;
private static Bundle mBundleRecyclerViewState;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ivRefresh = (ImageView) findViewById(R.id.ivRefresh);
progressBar = (ProgressBar) findViewById(R.id.progressBar);
rvUsers = (RecyclerView) findViewById(R.id.rvUsers);
layoutManager = new LinearLayoutManager(this);
rvUsers.setLayoutManager(layoutManager);
adapter = new MainAdapter(new ArrayList<>(), this);
rvUsers.setAdapter(adapter);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
@Override
protected void onPause()
{
super.onPause();
// save RecyclerView state
mBundleRecyclerViewState = new Bundle();
Parcelable listState = rvUsers.getLayoutManager().onSaveInstanceState();
mBundleRecyclerViewState.putParcelable(KEY_RECYCLER_STATE, listState);
}
@Override
protected void onResume()
{
super.onResume();
// restore RecyclerView state
if (mBundleRecyclerViewState != null) {
Parcelable listState = mBundleRecyclerViewState.getParcelable(KEY_RECYCLER_STATE);
rvUsers.getLayoutManager().onRestoreInstanceState(listState);
}
}
}
这篇关于旋转后无法还原滚动位置(RecyclerView)的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文