我正在关注我尝试使用FirebaseUI
检索数据的YouTube视频,但我无法在recyclerview
中显示任何数据。
这是代码
public class MemeFragment extends Fragment {
RecyclerView recyclerView;
FirebaseDatabase firebaseDatabase;
DatabaseReference myref;
FirebaseRecyclerAdapter<Datafileinfo, ShowDataViewHolder> firebaseRecyclerAdapter;
FirebaseRecyclerOptions<Datafileinfo> options;
public MemeFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_meme, container, false);
firebaseDatabase = FirebaseDatabase.getInstance();
myref = FirebaseDatabase.getInstance().getReference("memes");
recyclerView = (RecyclerView) view.findViewById(R.id.recyc);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
options = new FirebaseRecyclerOptions.Builder<Datafileinfo>()
.setQuery(myref, Datafileinfo.class)
.build();
return view;
}
@Override
public void onStart() {
super.onStart();
firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<Datafileinfo, ShowDataViewHolder>
(options) {
@Override
protected void onBindViewHolder(@NonNull ShowDataViewHolder holder, int position, @NonNull Datafileinfo model) {
holder.ImageTitle(model.getTitle());
holder.ImageUrl(model.getImage());
}
@Override
public ShowDataViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.custo, parent, false);
return new ShowDataViewHolder(view);
}
};
recyclerView.setAdapter(firebaseRecyclerAdapter);
}
public static class ShowDataViewHolder extends RecyclerView.ViewHolder {
private ImageView imageView;
private TextView textView;
public ShowDataViewHolder(View itemView) {
super(itemView);
imageView = (ImageView) itemView.findViewById(R.id.imageView);
textView = (TextView) itemView.findViewById(R.id.textView);
}
private void ImageTitle(String title) {
textView.setText(title);
}
private void ImageUrl(String url) {
Glide.with(itemView.getContext()).
load(url).
into(imageView);
}
}
}
和datafileinfo是getter和setter类我也获得了Internet权限。注意我能从firebase获取单个值但是对于多个值,我遇到的问题是这是数据库。 在哪里我做错了任何想法??
答案 0 :(得分:0)
为ViewHolder创建单独的类
public class ShowDataViewHolder extends RecyclerView.ViewHolder{
private ImageView imageView;
private TextView textView;
public ShowDataViewHolder (View itemView) {
super(itemView);
imageView = (ImageView)itemView.findViewById(R.id.imageView);
textView = (TextView) itemView.findViewById(R.id.textView);
}
}
在您的MenuFragment中添加
DatabaseReference mDatabaseMemes= //your reference to memes node
FirebaseRecyclerAdapter<yourModel, ShowDataViewHolder> adapter= new FirebaseRecyclerAdapter<yourModel, ShowDataViewHolder>(yourModel.class, R.layout.yourLayout,
ShowDataViewHolder.class,mDatabaseMemes) {
@Override
protected void populateViewHolder(ShowDataViewHolder viewHolder, yourModel model, int position) {
viewHolder.textView.setText(model.getTitle());
Glide.with(context)
.load(model.getImage())
.fitCenter()
.into(viewHolder.imageView);
}
};
recyclerView.setAdapter(adapter);
}
确认您的模型类的字符串标题和图像与模因节点下的子名称相同。