RecyclerView在notifyDataSetChanged()上闪烁;

Question

在主持人将此问题作为重复问题删除之前，请阅读下面的内容

好的，我尝试了不同的答案，但都不适合我例如，我已经禁用了动画，但它不起作用我试图使用这个，但我没有使用getItemID所以我不知道该怎么做

这是我的代码

Home_Fragment.java//好的，我只给出了我认为需要的部分代码，但如果你想看到整个代码，请告诉我，我会更新它

public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_home, container, false);
postRecyclerView.setItemAnimator(null);
getData();
return view;
}
private void getData() {
databaseReference.addValueEventListener(new ValueEventListener() {
@SuppressLint("NotifyDataSetChanged")
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
if (snapshot.exists()) {
shimmerFrameLayout.stopShimmer();
shimmerFrameLayout.setVisibility(View.GONE);
postRecyclerView.setVisibility(View.VISIBLE);
mUploads.clear();
for (DataSnapshot dataSnapshot : snapshot.getChildren()) {
Upload upload = dataSnapshot.getValue(Upload.class);
assert upload != null;
upload.setmKey(dataSnapshot.getKey());
mUploads.add(upload);

}
}
postsAdapter.setUploads(mUploads);
//notify the adapter
postsAdapter.notifyDataSetChanged();
loading = true;
}

@Override
public void onCancelled(@NonNull DatabaseError error) {
loading = true;
}
});
}

PostAdapter_Home.java

public class PostAdapter_Home extends RecyclerView.Adapter<PostAdapter_Home.PostViewHolder> {
public static List<Upload> mUploads;
public Context mcontext;
public PostAdapter_Home(Context context, List<Upload> uploads) {
mUploads = uploads;
mcontext = context;
}

@NonNull
@Override
public PostViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view;
view = LayoutInflater.from(mcontext).inflate(R.layout.ex_home, parent, false);
return new PostViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull PostViewHolder holder, int position) {
Shimmer shimmer = new Shimmer.ColorHighlightBuilder()
.setBaseColor(Color.parseColor("#F3F3F3"))
.setBaseAlpha(1)
.setHighlightColor(Color.parseColor("#E7E7E7"))
.setHighlightAlpha(1)
.setDropoff(50)
.build();
ShimmerDrawable shimmerDrawable = new ShimmerDrawable();
shimmerDrawable.setShimmer(shimmer);
Upload uploadCurrent = mUploads.get(position);
Glide.with(mcontext)
.load(uploadCurrent.getmImageUrl())
.diskCacheStrategy(DiskCacheStrategy.AUTOMATIC)
.placeholder(shimmerDrawable)
.centerCrop()
.fitCenter()
.into(holder.imageView);
//        holder.imageView.setOnClickListener(view -> changeScaleType(holder, position));
}

@Override
public int getItemCount() {
return mUploads.size();
}
public void setUploads(List<Upload> uploads){
mUploads=uploads;
}
public static class PostViewHolder extends RecyclerView.ViewHolder {
private final ShapeableImageView imageView;
public PostViewHolder(@NonNull View itemView) {
super(itemView);
imageView = itemView.findViewById(R.id.imagePostHome);
}

}
}

Upload.java

package com.example.myappnotfinal.AdaptersAndMore;
import com.google.firebase.database.Exclude;
public class Upload {
private String mImageUrl;
private String mKey;
private String mUserName;
private String mComment;
public Upload() {
}
public Upload(String imageUrl) {
mImageUrl = imageUrl;
}
public String getmUserName() {
return mUserName;
}
public void setmUserName(String mUserName) {
this.mUserName = mUserName;
}
public String getmComment() {
return mComment;
}
public void setmComment(String mComment) {
this.mComment = mComment;
}
public String getmImageUrl() {
return mImageUrl;
}
public void setmImageUrl(String mImageUrl) {
this.mImageUrl = mImageUrl;
}
@Exclude
public String getmKey() {
return mKey;
}
@Exclude
public void setmKey(String Key) {
this.mKey = Key;
}
}

Answer 1

试试ListAdapter，它会帮你管理这些动画。要实现这一点，我们需要编写一些样板类。

首先，让我们创建适配器。

public class YourAdapter extends ListAdapter<YourModelClass, YourAdapter.YourViewHolder> {
public YourAdapter(@NonNull DiffUtil.ItemCallback<YourModelClass> diffCallback) {
super(diffCallback);
}
public static class YourViewHolder extends RecyclerView.ViewHolder {

private TextView textViewId;
private TextView textViewName;
private YourViewHolder(View view) {
super(view);
textViewId = view.findViewById(R.id.textViewId);
textViewName = view.findViewById(R.id.textViewName);
}
static YourViewHolder create(ViewGroup parent) {
return new YourViewHolder(
LayoutInflater.from(parent.getContext())
.inflate(
R.layout.your_layout,
parent,
false
)
);
}
void bind(YourModelClass model) {
textViewId.setText(String.valueOf(model.getId()));
textViewName.setText(model.getName());
}
}
@NonNull
@Override
public YourViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
return YourViewHolder.create(parent);
}
@Override
public void onBindViewHolder(@NonNull YourViewHolder holder, int position) {
holder.bind(getItem(position));
}
}

现在，让我们创建用DiffUtill算法比较列表项的类。在areItemsTheSame中，您需要使用唯一键来比较项目。在areContentsTheSame中，我们只比较两个实例。

public class YourItemCallback extends DiffUtil.ItemCallback<YourModelClass> {
@Override
public boolean areItemsTheSame(@NonNull YourModelClass oldItem, @NonNull YourModelClass newItem) {
return oldItem.getId() == newItem.getId();
}
@Override
public boolean areContentsTheSame(@NonNull YourModelClass oldItem, @NonNull YourModelClass newItem) {
return Objects.equals(oldItem, newItem);
}
}

最后，让我们将数据发送到适配器。注意，submitList方法接收适配器

中指定的类型的列表ListAdapter<YourModelClass, YourAdapter.YourViewHolder>

List<YourModelClass> yourList = Arrays.asList(
new YourModelClass(1, "John"),
new YourModelClass(1, "Mac"),
new YourModelClass(1, "Gu"),
new YourModelClass(1, "Gabriel")
);
RecyclerView recyclerView = findViewById(R.id.recyclerView);
YourAdapter yourAdapter = new YourAdapter(new YourItemCallback());
recyclerView.setAdapter(yourAdapter);
yourAdapter.submitList(yourList);