Firebase DatabaseException无法转换String类型的对象 [英] Firebase DatabaseException Can't convert object of type String

问题描述

尝试将一组数据加载到 FirebaseRecyclerAdapter

$时出现这个奇怪的错误b $ b

com.google.firebase.database.DatabaseException：无法将类型为java.lang.String的对象
转换为类型
com.magn.test.android.model.ProfilesData

引用这个类：

  @IgnoreExtraProperties 
 public class ProfilesData {
 
 public String forename; 
 public String surname; 
 public String quote; 
 public String birth; 
 public String demise; 
 public String id; 
 
 $ b public ProfilesData（）{
 
} 
 
 public ProfilesData（String forename，String surname，String quote，String birth，String demise，String id）{
 this.forename = forename; 
 this.surname = surname; 
 this.quote = quote; 
 this.birth = birth; 
 this.demise =死亡; 
 this.id = id; 
 
 
 
 $ b public String getForename（）{
 return forename; 
} 
 
 public void setForename（String forename）{
 this.forename = forename; 
} 
 
 public String getSurname（）{
 return surname; 
 
 $ b $ public void setSurname（String surname）{
 this.surname = surname; 
} 
 
 public String getQuote（）{
 return quote; 
} 
 
 public void setQuote（String quote）{
 this.quote = quote; 
} 
 
 public String getBirth（）{
 return birth; 
} 
 
 public void setBirth（String birth）{
 this.birth = birth; 
} 
 
 public String getDemise（）{
 return demise; 
} 
 
 public void setDemise（String demise）{
 this.demise = demise; 
} 
 
 public String getId（）{
 return id; 
} 
 
 public void setId（String id）{
 this.id = id; 
 
 code 
 
 
 
 
 
 
 
 
 
 
 $ b $ p 
 
 
 $ b 
如果我可以将问题的范围缩小到某个函数/方法，那将会更容易，但是适配器在完成时会将数据打印出来。它只是不会在布局结束，应用程序完成后崩溃。
 
 
 
这是活动：
  @Override 
保护无效的onCreate（Bundle savedInstanceState）{
 super.onCreate（savedInstanceState）; 
 setContentView（R.layout.activity_selection）; 
 
 recyclerView =（RecyclerView）findViewById（R.id.recycler_view）; 
 
 recyclerView.setLayoutManager（新的LinearLayoutManager（this））; 
 
 mAuth = FirebaseAuth.getInstance（）; 
 mAuth.addAuthStateListener（this）; 
 
 //初始化数据库
 user = FirebaseAuth.getInstance（）。getCurrentUser（）; 
 database = FirebaseDatabase.getInstance（）。getReference（）。child（users）。child（user.getUid（））。child（profiles_info）。child（1）; 
 
 
 
 
 @覆盖
 public void onAuthStateChanged（@NonNull FirebaseAuth firebaseAuth）{
 
} 
 
 
 
 @Override 
 protected void onStart（）{
 super.onStart（）; 
 
 FirebaseRecyclerAdapter< ProfilesData，ProfilesViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter< ProfilesData，ProfilesViewHolder>（
 ProfilesData.class，R.layout.list_item，ProfilesViewHolder.class，database）{
 @Override 
 protected void populateViewHolder（ProfilesViewHolder viewHolder，ProfilesData model ，int position）{
 
 System.out.println（NAME ARE：+ model.getForename（））; 
 
 viewHolder.setName（model.getForename（）++ model.getSurname（））; 
 viewHolder.setDates（model.getBirth（）++ model.getDemise（））; 
 
 
} 
}; 
 
 //滚动到新消息的底部
 firebaseRecyclerAdapter.registerAdapterDataObserver（new RecyclerView.AdapterDataObserver（）{
 @Override 
 public void onItemRangeInserted（int positionStart，int itemCount ）{
 
} 
}）; 
 
 recyclerView.setAdapter（firebaseRecyclerAdapter）; 
 
} 
 
 
 
 
 
 
 $ b / ** 
 * ViewHolder在将profiledata加载到适配器时应用图形更改：
 * / 
 
 public static class ProfilesViewHolder extends RecyclerView.ViewHolder {
 
 private final TextView name_tv; 
 private final TextView date_tv; 
 
 public ProfilesViewHolder（View itemView）{
 super（itemView）; 
 name_tv =（TextView）itemView.findViewById（R.id.profile_name_tv）; 
 date_tv =（TextView）itemView.findViewById（R.id.profile_dates_tv）; 
} 
 
 public void setName（String name）{
 name_tv.setText（name）; 
} 
 
 public void setDates（String dates）{
 date_tv.setText（dates）; 
 
 
 $ b  
 
 
解决方案
 
 
 
 $ p $  database = FirebaseDatabase.getInstance（） .getReference（）子（ 用户）子（user.getUid（））子（ profiles_info）。; 
  

给了我正确的位置，它可以正确加载一切。检查你的路径！


I'm getting this strange error when trying to load a set of data into the FirebaseRecyclerAdapter

com.google.firebase.database.DatabaseException: Can't convert object of type java.lang.String to type com.magn.test.android.model.ProfilesData

Referring to this class:

@IgnoreExtraProperties
public class ProfilesData {

public String forename;
public String surname;
public String quote;
public String birth;
public String demise;
public String id;


public ProfilesData(){

}

public ProfilesData(String forename, String surname, String quote, String birth, String demise, String id){
    this.forename = forename;
    this.surname = surname;
    this.quote = quote;
    this.birth = birth;
    this.demise = demise;
    this.id = id;
}



public String getForename() {
    return forename;
}

public void setForename(String forename) {
    this.forename = forename;
}

public String getSurname() {
    return surname;
}

public void setSurname(String surname) {
    this.surname = surname;
}

public String getQuote() {
    return quote;
}

public void setQuote(String quote) {
    this.quote = quote;
}

public String getBirth() {
    return birth;
}

public void setBirth(String birth) {
    this.birth = birth;
}

public String getDemise() {
    return demise;
}

public void setDemise(String demise) {
    this.demise = demise;
}

public String getId() {
    return id;
}

public void setId(String id) {
    this.id = id;
}

}

It would've been easier if I could narrow the issue down to a certain function/method, but the adapter does fetch the data as I print it out when it's done. It just doesn't end up in the layout, and the app crashes short after it is done.

Here's the Activity:

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_selection);

    recyclerView = (RecyclerView) findViewById(R.id.recycler_view);

    recyclerView.setLayoutManager(new LinearLayoutManager(this));

    mAuth = FirebaseAuth.getInstance();
    mAuth.addAuthStateListener(this);

    //Initialize database
    user = FirebaseAuth.getInstance().getCurrentUser();
    database = FirebaseDatabase.getInstance().getReference().child("users").child(user.getUid()).child("profiles_info").child("1");


}


@Override
public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {

}



@Override
protected void onStart() {
    super.onStart();

    FirebaseRecyclerAdapter<ProfilesData, ProfilesViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<ProfilesData, ProfilesViewHolder>(
            ProfilesData.class, R.layout.list_item, ProfilesViewHolder.class, database) {
        @Override
        protected void populateViewHolder(ProfilesViewHolder viewHolder, ProfilesData model, int position) {

            System.out.println("NAME ARE: " + model.getForename());

            viewHolder.setName(model.getForename() + " " + model.getSurname());
            viewHolder.setDates(model.getBirth() + " " + model.getDemise());


        }
    };

    // Scroll to bottom on new messages
    firebaseRecyclerAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
        @Override
        public void onItemRangeInserted(int positionStart, int itemCount) {

        }
    });

    recyclerView.setAdapter(firebaseRecyclerAdapter);

}







/**
 * ViewHolder to apply graphical changes when loading profiledata into adapter:
 */

public static class ProfilesViewHolder extends RecyclerView.ViewHolder {

    private final TextView name_tv;
    private final TextView date_tv;

    public ProfilesViewHolder(View itemView){
        super(itemView);
        name_tv = (TextView) itemView.findViewById(R.id.profile_name_tv);
        date_tv = (TextView) itemView.findViewById(R.id.profile_dates_tv);
    }

    public void setName(String name){
        name_tv.setText(name);
    }

    public void setDates(String dates){
        date_tv.setText(dates);
    }

}

解决方案

Simple enough I simply was looking one "child" too far in my database:

database = FirebaseDatabase.getInstance().getReference().child("users").child(user.getUid()).child("profiles_info"); 

gave me the correct location and it could load everything correctly. Check your paths!

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