问题描述
由于某种原因，我的 inflate 没有显示 xml 文件，这是为什么？
我的 home.java：
package com.example.soulforge.fragments;
import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.linearlayoutmanager;
import androidx.recyclerview.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.example.soulforge.R;
import com.example.soulforge.adapter.HomeAdapter;
import com.example.soulforge.model.HomeModel;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.firestore.CollectionReference;
import com.google.firebase.firestore.DocumentReference;
import com.google.firebase.firestore.EventListener;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.FirebaseFirestoreException;
import com.google.firebase.firestore.QueryDocumentSnapshot;
import com.google.firebase.firestore.QuerySnapshot;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
public class Home extends Fragment {
private RecyclerView recyclerView;
HomeAdapter adapter;
private List<HomeModel> list;
private FirebaseUser user;
public Home() {
// required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_home,container,false);
}
@Override
public void onViewCreated(@NonNull View view,@Nullable Bundle savedInstanceState) {
super.onViewCreated(view,savedInstanceState);
init(view);
list = new ArrayList<>();
adapter = new HomeAdapter(list,getContext());
recyclerView.setAdapter(adapter);
loadDataFromFirestore();
}
private void init(View view) {
Toolbar toolbar = view.findViewById(R.id.toolbar);
if (getActivity() != null)
((AppCompatActivity) getActivity()).setSupportActionBar(toolbar);
recyclerView = view.findViewById(R.id.recyclerView);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new linearlayoutmanager(getContext()));
FirebaseAuth auth = FirebaseAuth.getInstance();
user = auth.getCurrentUser();
}
public void loadDataFromFirestore() {
CollectionReference reference = FirebaseFirestore.getInstance().collection("Users")
.document(user.getUid())
.collection("Post Images");
reference.addSnapshotListener(new EventListener<QuerySnapshot>() {
@Override
public void onEvent(@Nullable QuerySnapshot value,@Nullable FirebaseFirestoreException error) {
if (error != null) {
Log.e("Error: ",error.getMessage());
return;
}
if (value == null)
return;
for (QueryDocumentSnapshot snapshot : value) {
if (!snapshot.exists())
return;
HomeModel model = snapshot.toObject(HomeModel.class);
list.add(new HomeModel(
model.getUserName(),model.getProfileImage(),model.getimageUrl(),model.getUid(),model.getComments(),model.getDescription(),model.getId(),model.getTimestamp(),model.getLikeCount()
));
}
adapter.notifyDataSetChanged();
}
});
}
}
和我的 HomeAdapter.java：
package com.example.soulforge.adapter;
import android.content.Context;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import com.bumptech.glide.Glide;
import com.example.soulforge.R;
import com.example.soulforge.model.HomeModel;
import com.google.firebase.firestore.EventListener;
import com.google.firebase.firestore.QuerySnapshot;
import java.util.List;
import java.util.Random;
import de.hdodenhof.circleimageview.CircleImageView;
public class HomeAdapter extends RecyclerView.Adapter<HomeAdapter.HomeHolder>{
private List<HomeModel> list;
Context context;
public HomeAdapter(List<HomeModel> list,Context context) {
this.list = list;
this.context = context;
}
@NonNull
@Override
public HomeHolder onCreateViewHolder(@NonNull ViewGroup parent,int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.home_items,parent,false);
return new HomeHolder(view);
}
@Override
public void onBindViewHolder(@NonNull HomeHolder holder,int position) {
holder.userNameTv.setText(list.get(position).getUserName());
holder.timeTv.setText(""+list.get(position).getTimestamp());
int count = list.get(position).getLikeCount();
if(count ==0){
holder.likeCountTv.setVisibility(View.INVISIBLE);
}else if (count == 1){
holder.likeCountTv.setText(count + " like");
}else{
holder.likeCountTv.setText(count + " likes");
}
holder.descriptionTv.setText(list.get(position).getDescription());
Random random = new Random();
int color = Color.argb(255,random.nextInt(256),random.nextInt(256));
Glide.with(context.getApplicationContext())
.load(list.get(position).getProfileImage())
.placeholder(R.drawable.ic_person)
.timeout(6500)
.into(holder.profileImage);
Glide.with(context.getApplicationContext())
.load(list.get(position).getimageUrl())
.placeholder(new ColorDrawable(color))
.timeout(7000)
.into(holder.imageView);
}
@Override
public int getItemCount() {
return list.size();
}
static class HomeHolder extends RecyclerView.ViewHolder{
private CircleImageView profileImage;
private TextView userNameTv,timeTv,likeCountTv,descriptionTv;
private ImageView imageView;
private ImageButton likeBtn,commentBtn,shareBtn;
public HomeHolder(@NonNull View itemView) {
super(itemView);
profileImage = itemView.findViewById(R.id.profileImage);
imageView = itemView.findViewById(R.id.imageView);
userNameTv = itemView.findViewById(R.id.nameTv);
timeTv = itemView.findViewById(R.id.timeTv);
likeCountTv = itemView.findViewById(R.id.likeCountTv);
likeBtn = itemView.findViewById(R.id.likeBtn);
commentBtn = itemView.findViewById(R.id.commentBtn);
shareBtn = itemView.findViewById(R.id.shareBtn);
descriptionTv = itemView.findViewById(R.id.descTv);
}
}
}
所以我想知道我做了你应该做的一切，但是它没有在我的 fragment_home 上显示我的 home_items.xml。它只显示 fragment_home 仅缺少 home_items。有没有办法帮助解决这个问题，我已经被困在这里好几天了，想尝试解决这个问题:(
解决方法
可能是错误的，因为我没有检查详细信息。您能否尝试将adapter.notifydataset向上移动一个元素（即在}之前）。可能是错误的，但它似乎没有在正确的位置通知数据集更改在 for 快照循环内。可能又错了
,请移步
adapter = new HomeAdapter(list,getContext());
recyclerView.setAdapter(adapter);
在for循环结束的上方下方
adapter.notifydatachange();
因为您首先将列表传递给适配器，然后从 firebase 获取数据并始终在活动/片段的 onStart 中调用您的 loadDataFromFirestore() 此类方法，因为每次您的活动/片段从后台返回时都会执行 onstart前台停止后，onCreate 仅在您的活动/片段创建时调用一次。