我有一个mainactivity,其中包括带有ViewPager的TabLayout
我添加了3个选项卡,每个选项卡都有单独的 fragment ,其中包含一个recyclerview,并且这些recyclerviews有一个复选框,每当我滑动viewpager时,该复选框应同时更新/刷新(我将选中的位置保存在共享首选项中,并通过共享首选项进行更新)。
我的问题是,每当我选中tab1中的复选框时,tab2才更新/刷新,直到我向下滚动Recyclerview。并且tab3正常工作。
和,我在logcat中也收到了奇怪的警告。
03-05 09:35:53.345 4317-4327/com.example.rubin W/art: Suspending all threads took: 6.805ms
03-05 09:35:58.310 4317-4317/com.example.rubin W/FragmentManager: moveToState: Fragment state for Tab3{10a5f1f0 #2 id=0x7f0d00b6} not updated inline; expected state 3 found 2
03-05 09:36:01.363 4317-4317/com.example.rubin W/FragmentManager: moveToState: Fragment state for Tab1{2d9aa887 #1 id=0x7f0d00b6} not updated inline; expected state 3 found 2
我的PagerAdapter
public class PagerAdapter1 extends FragmentStatePagerAdapter {
int mNumOfTabs;
public PagerAdapter1(FragmentManager fm, int NumOfTabs) {
super(fm);
this.mNumOfTabs = NumOfTabs;
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return new Tab1();
case 1:
return new Tab2();
case 2:
return new Tab3();
default:
return null;
}
}
@Override
public int getCount() {
return mNumOfTabs;
}
}
Tablayout OnPageChangelistener
final PagerAdapter1 adapter = new PagerAdapter1
(getSupportFragmentManager(), tabLayout1.getTabCount(), getApplicationContext());
viewPager1.setAdapter(adapter);
viewPager1.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout1));
tabLayout1.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
viewPager1.setCurrentItem(tab.getPosition());
adapter.notifyDataSetChanged();
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
每个 fragment 的代码。
public class Tab1 extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.home_tab1_recycler, container, false);
RecyclerView rv = (RecyclerView) v.findViewById(R.id.home_recyclerview);
LinearLayoutManager llm = new LinearLayoutManager(getContext());
rv.setLayoutManager(llm);
rv.setHasFixedSize(true); // to improve performance
rv.setAdapter(new HomeManager()); // the projectdatabase manager is assigner to the RV
return v;
}
public class HomeManager extends RecyclerView.Adapter<HomeManager.RecyclerViewHolder> {
int Length,h;
View v1;
ArrayList<String> PROJECT_ID = new ArrayList<String>();
Set<String> set;
List<String> selected;
public class RecyclerViewHolder extends RecyclerView.ViewHolder {
CheckBox mCheck;
RecyclerViewHolder(final View itemView) {
super(itemView);
mCheck = (CheckBox) itemView.findViewById(R.id.PROJECT_fav);
SharedPreferences pref = getContext().getSharedPreferences("MirSP", Context.MODE_PRIVATE);
set = pref.getStringSet("FAV", null);
if (set != null) {
selected = new ArrayList<String>(set);
} else {
selected = new ArrayList<String>();
}
mCheck.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
h = getAdapterPosition();
check = PROJECT_ID.get(h); // for saving the project id from json.
if (selected.contains(check)) {
selected.remove(check);
mCheck.setBackgroundResource(R.drawable.ic_favorite_white1_24dp);
Snackbar snackbar = Snackbar.make(v, "Property Unfavorited", Snackbar.LENGTH_SHORT);
snackbar.show();
} else {
selected.add(check);
mCheck.setBackgroundResource(R.drawable.ic_favorite_white_24dp);
Snackbar snackbar = Snackbar.make(v, "Property Favorited", Snackbar.LENGTH_SHORT);
snackbar.show();
}
Log.e("HF update checked", String.valueOf(selected));
Set<String> set = new HashSet<String>();
set.addAll(selected);
SharedPreferences pref = getContext().getSharedPreferences("MirSP", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
editor.putStringSet("FAV", set);
editor.commit();
}
}
});
@Override
public RecyclerViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
v1 = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.recyclerview_item, viewGroup, false);
return new RecyclerViewHolder(v1);
}
@Override
public void onBindViewHolder(final RecyclerViewHolder viewHolder, int i) {
SharedPreferences pref = getContext().getSharedPreferences("MirSP", Context.MODE_PRIVATE);
set = pref.getStringSet("FAV", null);
if (set != null) {
selected = new ArrayList<String>(set);
} else {
selected = new ArrayList<String>();
}
Log.e("HF update UI", String.valueOf(selected));
if (String.valueOf(selected).contains(String.valueOf(PROJECT_ID.get(i)))) {
viewHolder.mCheck.setBackgroundResource(R.drawable.ic_favorite_white_24dp);
} else {
viewHolder.mCheck.setBackgroundResource(R.drawable.ic_favorite_white1_24dp);
}
}
@Override
public int getItemCount() {
//Code for Total length of json
return Length;
}
最佳答案
FragmentPagerAdapter
在 Activity fragment 的邻域上调用setUserVisibleHint(true|false)
,这会更改该 fragment 的状态。
这至少是“奇怪的警告消息”的答案,但它可能无法解决您的问题。
关于如何解决该警告消息的评论,我创建了自己的FragmentPagerAdapter,如下所示:
public abstract class AbstractTabPagerAdapter extends PagerAdapter {
private static final String TAG = AbstractTabPagerAdapter.class.getCanonicalName();
private final FragmentManager mFragmentManager;
private FragmentTransaction mCurTransaction;
private Fragment mCurrentPrimaryItem = null;
public AbstractTabPagerAdapter(FragmentManager fragmentManager) {
mFragmentManager = fragmentManager;
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
if (mCurTransaction == null) {
throw new IllegalArgumentException("current transaction must not be null");
}
String fragmentTag = makeFragmentName(container.getId(), position);
Fragment fragment = (Fragment) mFragmentManager.findFragmentByTag(fragmentTag);
if (fragment != null) {
mCurTransaction.attach(fragment);
Log.d(TAG, "Attaching existing fragment " + fragment + " at position " + position);
//mCurTransaction.add(container.getId(), fragment, makeFragmentName(container.getId(), position));
} else {
fragment = getItem(position);
mCurTransaction.add(container.getId(), fragment, fragmentTag);
Log.d(TAG, "Attaching new fragment " + fragment + " at position " + position);
}
if (fragment != mCurrentPrimaryItem) {
fragment.setMenuVisibility(false);
//fragment.setUserVisibleHint(false);
}
return fragment;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
if (mCurTransaction == null) {
throw new IllegalArgumentException("current transaction must not be null");
}
mCurTransaction.detach((Fragment) object);
//mCurTransaction.remove((Fragment)object);
}
@Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
//super.setPrimaryItem(container, position, object);
Fragment fragment = (Fragment) object;
if (fragment != mCurrentPrimaryItem) {
Log.d(TAG, "set Primary item " + position + " to " + fragment);
if (mCurrentPrimaryItem != null) {
mCurrentPrimaryItem.setMenuVisibility(false);
// this command unexpectedly changes the state of the fragment which leads to a warning message and possible some strange behaviour
//mCurrentPrimaryItem.setUserVisibleHint(false);
}
if (fragment != null) {
fragment.setMenuVisibility(true);
//fragment.setUserVisibleHint(true);
}
mCurrentPrimaryItem = fragment;
}
}
@Override
public boolean isViewFromObject(View view, Object fragment) {
return ((Fragment) fragment).getView() == view;
}
public abstract Fragment getItem(int position);
@Override
public void startUpdate(ViewGroup container) {
super.startUpdate(container);
if (mCurTransaction != null) {
throw new IllegalArgumentException("current transaction must not be null");
}
mCurTransaction = mFragmentManager.beginTransaction();
Log.d(TAG, "FragmentTransaction started");
}
@Override
public void finishUpdate(ViewGroup container) {
if (mCurTransaction != null) {
mCurTransaction.commit();
mCurTransaction = null;
//mFragmentManager.executePendingTransactions();
Log.d(TAG, "FragmentTransaction committed");
} else {
throw new IllegalArgumentException("current transaction must not be null");
}
}
private String makeFragmentName(int viewId, int position) {
if (viewId <= 0)
throw new IllegalArgumentException("viewId " + viewId);
return "tabpageradptr:" + getPageTitle(position) + ":" + viewId + ":" + position;
}
}
警告消息现在消失了,目前我还没有遇到任何缺陷-但是我仍处于研究之中。