我遇到了错误E/RecyclerView: No adapter attached; skipping layout，但我不知道是什么原因，因为我刚刚研究了这个片段。
我已经对此进行了搜索，并按照步骤进行操作，但是仍然出现错误。
这是我的适配器：
public class BlogRecyclerAdapter extends RecyclerView.Adapter<BlogRecyclerAdapter.ViewHolder> {
public List<BlogPost> blog_list;
public List<User> user_list;
public Context context;
private FirebaseFirestore firebaseFirestore;
private FirebaseAuth firebaseAuth;
public BlogRecyclerAdapter(List<BlogPost> blog_list,List<User> user_list){
this.blog_list = blog_list;
this.user_list = user_list;
}
@NonNull
@Override
public BlogRecyclerAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.single_list_view, parent, false);
context = parent.getContext();
firebaseFirestore = FirebaseFirestore.getInstance();
firebaseAuth = FirebaseAuth.getInstance();
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull final ViewHolder holder, final int position) {
holder.setIsRecyclable(false);
final String blogPostId = blog_list.get(position).BlogPostId;
final String currentUserId = firebaseAuth.getCurrentUser().getUid();
String desc_data = blog_list.get(position).getDesc();
holder.setDescText(desc_data);
String image_url = blog_list.get(position).getImage_url();
String thumbUri = blog_list.get(position).getThumbnail();
holder.setBlogImage(image_url, thumbUri);
String blog_user_id = blog_list.get(position).getUser_id();
holder.blogDeletebtn.setEnabled(true);
holder.blogDeletebtn.setVisibility(View.VISIBLE);
firebaseFirestore.collection("Users").document(blog_user_id).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
if(task.isSuccessful()){
String userName = task.getResult().getString("name");
String userImage = task.getResult().getString("image");
holder.setUserData(userName, userImage);
}
else{
//error
}
}
});
try {
long millisecond = blog_list.get(position).getTimestamp().getTime();
String dateString = DateFormat.format("MM/dd/yyyy", new Date(millisecond)).toString();
holder.setTime(dateString);
} catch (Exception e) {
Toast.makeText(context, "Exception : " + e.getMessage(), Toast.LENGTH_SHORT).show();
}
//new query para sa counter ng like
firebaseFirestore.collection("Posts")
.document(blogPostId)
.collection("Likes").addSnapshotListener(new EventListener<QuerySnapshot>() {
@Override
public void onEvent(@Nullable QuerySnapshot queryDocumentSnapshots, @Nullable FirebaseFirestoreException e) {
if(!queryDocumentSnapshots.isEmpty()){
int count = queryDocumentSnapshots.size();
holder.updatesLikeCount(count);
}
else
{
holder.updatesLikeCount(0);
}
}
});
//new query sa likes
firebaseFirestore.collection("Posts")
.document(blogPostId)
.collection("Likes")
.document(currentUserId).addSnapshotListener(new EventListener<DocumentSnapshot>() {
@Override
public void onEvent(@Nullable DocumentSnapshot documentSnapshot, @Nullable FirebaseFirestoreException e) {
if(documentSnapshot.exists()){
holder.blogLikebtn.setImageDrawable(context.getDrawable(R.mipmap.action_like_accent));
}
else
{
holder.blogLikebtn.setImageDrawable(context.getDrawable(R.mipmap.action_like_gray));
}
}
});
//dito gagana yung likes
holder.blogLikebtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
firebaseFirestore.collection("Posts")
.document(blogPostId)
.collection("Likes")
.document(currentUserId).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
if(!task.getResult().exists()){
Map<String, Object> likesMap = new HashMap<>();
likesMap.put("timestamp", FieldValue.serverTimestamp());
firebaseFirestore.collection("Posts")
.document(blogPostId)
.collection("Likes")
.document(currentUserId)
.set(likesMap);
}
else{
firebaseFirestore.collection("Posts")
.document(blogPostId)
.collection("Likes")
.document(currentUserId)
.delete();
}
}
});
}
});
holder.blogCommentBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent commentIntent = new Intent(context, CommentsActivity.class);
commentIntent.putExtra("blog_post_id", blogPostId);
context.startActivity(commentIntent);
}
});
holder.blogDeletebtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
firebaseFirestore.collection("Posts").document(blogPostId).delete().addOnSuccessListener(new OnSuccessListener<Void>() {
@Override
public void onSuccess(Void aVoid) {
blog_list.remove(position);
user_list.remove(position);
}
});
}
});
}
@Override
public int getItemCount() {
return blog_list.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
private View mView;
private TextView descView,blogDate,blogUserName,blogLikeCount;
private ImageView blogImageView,blogLikebtn,blogCommentBtn;
private CircleImageView blogUserImage;
private Button blogDeletebtn;
public ViewHolder(View itemView) {
super(itemView);
mView = itemView;
blogLikebtn = mView.findViewById(R.id.blog_like_btn);
blogCommentBtn = mView.findViewById(R.id.blog_comment_btn);
blogDeletebtn = mView.findViewById(R.id.blog_delete_btn);
}
private void setDescText(String descText){
descView = mView.findViewById(R.id.blog_desc);
descView.setText(descText);
}
private void setBlogImage(String downloadUri, String thumbUri){
blogImageView = mView.findViewById(R.id.blog_image);
RequestOptions requestOptions = new RequestOptions();
requestOptions.placeholder(R.drawable.header1);
Glide.with(context).applyDefaultRequestOptions(requestOptions).load(downloadUri).thumbnail
(Glide.with(context).load(thumbUri)).into(blogImageView);
}
private void setTime(String date){
blogDate = mView.findViewById(R.id.blog_date);
blogDate.setText(date);
}
private void setUserData(String name, String image){
blogUserImage = mView.findViewById(R.id.blog_user_image);
blogUserName = mView.findViewById(R.id.blog_username);
blogUserName.setText(name);
RequestOptions placeholderOptions = new RequestOptions();
placeholderOptions.placeholder(R.drawable.messenger_button_send_round_shadow);
Glide.with(context).applyDefaultRequestOptions(placeholderOptions).load(image).into(blogUserImage);
}
public void updatesLikeCount(int count){
blogLikeCount = mView.findViewById(R.id.blog_like_count);
blogLikeCount.setText(count + "Likes");
}
}
}
这是我的片段：
public class HomeFragment extends Fragment {
private RecyclerView blog_list_view;
private List<BlogPost> blog_list;
private List<User> user_list;
private FirebaseFirestore firebaseFirestore;
private FirebaseAuth firebaseAuth;
private BlogRecyclerAdapter blogRecyclerAdapter;
private DocumentSnapshot lastVisible;
private boolean isFirstPageFirstLoad = true;
public HomeFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, final ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_home, container, false);
blog_list = new ArrayList<>();
user_list = new ArrayList<>();
blog_list_view = view.findViewById(R.id.blog_list_view);
firebaseAuth = FirebaseAuth.getInstance();
blogRecyclerAdapter = new BlogRecyclerAdapter(blog_list, user_list);
blog_list_view.setLayoutManager(new LinearLayoutManager(container.getContext()));
blog_list_view.setAdapter(blogRecyclerAdapter);
blog_list_view.setHasFixedSize(true);
if (firebaseAuth.getCurrentUser() != null) {
firebaseFirestore = FirebaseFirestore.getInstance();
blog_list_view.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
Boolean reachBottom = !recyclerView.canScrollVertically(1);
if (reachBottom) {
loadMorePost();
}
}
});
Query firstQuery = firebaseFirestore.collection("Posts")
.orderBy("timestamp", Query.Direction.DESCENDING)
.limit(10);
firstQuery.addSnapshotListener(getActivity(), new EventListener<QuerySnapshot>() {
@Override
public void onEvent(@Nullable QuerySnapshot queryDocumentSnapshots, @Nullable FirebaseFirestoreException e) {
if (!queryDocumentSnapshots.isEmpty()) {
if (isFirstPageFirstLoad) {
lastVisible = queryDocumentSnapshots.getDocuments()
.get(queryDocumentSnapshots.size() - 1);
blog_list.clear();
user_list.clear();
}
for (DocumentChange doc : queryDocumentSnapshots.getDocumentChanges()) {
if (doc.getType() == DocumentChange.Type.ADDED) {
String blogPostId = doc.getDocument().getId();
final BlogPost blogPost = doc.getDocument().toObject(BlogPost.class).withId(blogPostId);
String blogUserId = doc.getDocument().getString("user_id");
firebaseFirestore.collection("Users").document(blogUserId).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
if (task.isSuccessful()) {
User user = task.getResult().toObject(User.class);
user_list.add(user);
if (isFirstPageFirstLoad) {
user_list.add(user);
blog_list.add(blogPost);
} else {
user_list.add(0, user);
blog_list.add(0, blogPost);
}
blogRecyclerAdapter.notifyDataSetChanged();
}
}
});
}
isFirstPageFirstLoad = false;
}
}
}
});
}
// Inflate the layout for this fragment
return view;
}
private void loadMorePost(){
Query nextQuery = firebaseFirestore.collection("Posts")
.orderBy("timestamp", Query.Direction.DESCENDING)
.startAfter(lastVisible)
.limit(10);
nextQuery.addSnapshotListener(getActivity(), new EventListener<QuerySnapshot>() {
@Override
public void onEvent(@Nullable QuerySnapshot queryDocumentSnapshots, @Nullable FirebaseFirestoreException e) {
if(!queryDocumentSnapshots.isEmpty()) {
lastVisible = queryDocumentSnapshots.getDocuments()
.get(queryDocumentSnapshots.size() - 1);
for (DocumentChange doc : queryDocumentSnapshots.getDocumentChanges()) {
if (doc.getType() == DocumentChange.Type.ADDED) {
String blogPostId = doc.getDocument().getId();
final BlogPost blogPost = doc.getDocument().toObject(BlogPost.class).withId(blogPostId);
String blogUserId = doc.getDocument().getString("user_id");
firebaseFirestore.collection("Users").document(blogUserId).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
if(task.isSuccessful()){
User user = task.getResult().toObject(User.class);
user_list.add(user);
user_list.add(user);
blog_list.add(blogPost);
blogRecyclerAdapter.notifyDataSetChanged();
}
}
});
}
}
}
}
});
}
}
这是我的活动
public class Feed extends AppCompatActivity {
private Toolbar mainToolbar;
FirebaseAuth firebaseAuth;
private FloatingActionButton addPostbtn;
private FirebaseFirestore firebaseFirestore;
private String current_user_id;
private BottomNavigationView feedbottomNav;
private HomeFragment homeFragment;
private NotificationFragment notificationFragment;
private AccountFragment accountFragment;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_feed);
FirebaseApp.initializeApp(this);
firebaseAuth = FirebaseAuth.getInstance();
firebaseFirestore = FirebaseFirestore.getInstance();
mainToolbar = findViewById(R.id.main_toolbar);
setSupportActionBar(mainToolbar);
getSupportActionBar().setTitle("Feed");
if(firebaseAuth != null) {
feedbottomNav = findViewById(R.id.feedBottomNav);
//FRAGMENTS KO
homeFragment = new HomeFragment();
notificationFragment = new NotificationFragment();
accountFragment = new AccountFragment();
initializeFragment();
feedbottomNav.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {
Fragment currentFragment = getSupportFragmentManager().findFragmentById(R.id.feed_container);
switch (menuItem.getItemId()) {
case R.id.bottom_home_fragment:
replaceFragment(homeFragment, currentFragment);
return true;
case R.id.bottom_account_fragment:
replaceFragment(accountFragment, currentFragment);
return true;
case R.id.bottom_notification_fragment:
replaceFragment(notificationFragment, currentFragment);
return true;
default:
return false;
}
}
});
addPostbtn = findViewById(R.id.add_post_btn);
addPostbtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startActivity(new Intent(Feed.this, NewPostActivity.class));
finish();
}
});
}
}
private void initializeFragment() {
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.add(R.id.feed_container, homeFragment);
fragmentTransaction.add(R.id.feed_container, notificationFragment);
fragmentTransaction.add(R.id.feed_container, accountFragment);
fragmentTransaction.hide(notificationFragment);
fragmentTransaction.hide(accountFragment);
fragmentTransaction.commit();
}
@Override
protected void onStart() {
super.onStart();
FirebaseUser currentUser = FirebaseAuth.getInstance().getCurrentUser();
if (currentUser == null) {
startActivity(new Intent(Feed.this, MainActivity.class));
finish();
} else {
current_user_id = firebaseAuth.getCurrentUser().getUid();
firebaseFirestore.collection("Users").document(current_user_id).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
if (task.isSuccessful()) {
if (!task.getResult().exists()) {
startActivity(new Intent(Feed.this, AccountSettings.class));
finish();
}
} else {
String errorMessage = task.getException().getMessage();
Toast.makeText(Feed.this, "Error: " + errorMessage, Toast.LENGTH_LONG).show();
}
}
});
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()){
case R.id.action_logout:
logOut();
return true;
case R.id.action_settings_btn:
startActivity(new Intent(Feed.this, AccountSettings.class));
return true;
default:
return false;
}
}
private void logOut(){
firebaseAuth.signOut();
finish();
startActivity(new Intent(Feed.this,MainActivity.class));
}
private void replaceFragment(Fragment fragment, Fragment currentFragment){
//paglipat ng fragment
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
if(fragment == homeFragment){
fragmentTransaction.hide(accountFragment);
fragmentTransaction.hide(notificationFragment);
}
if(fragment == accountFragment){
fragmentTransaction.hide(homeFragment);
fragmentTransaction.hide(notificationFragment);
}
if(fragment == notificationFragment){
fragmentTransaction.hide(homeFragment);
fragmentTransaction.hide(accountFragment);
}
fragmentTransaction.show(fragment);
//fragmentTransaction.replace(R.id.main_container, fragment);
fragmentTransaction.commit();
}
}
这是我的片段布局
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/blog_list_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
这是我的活动布局
<FrameLayout
android:id="@+id/feed_container"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="@+id/feedBottomNav"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/main_toolbar">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/blog_list_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
当我发布数据时，将检索数据并将其显示在recyclerview中，并且应该在feed上看到recycler视图，但是我一直收到该错误，请帮忙。