Working with Firebase and stuck at a point with error
Can’t convert object of type java.lang.String to type (model class)
codes are follows
MainActivity.kt
package com.newhome.smarty
import android.os.Bundle
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.recyclerview.widget.LinearLayoutManager
import com.firebase.ui.database.FirebaseRecyclerOptions
import com.google.firebase.auth.FirebaseAuth
import com.google.firebase.database.*
import kotlinx.android.synthetic.main.activity_switch.*
class MainActivity : AppCompatActivity() {
private lateinit var adapter: MyAdapter
private var mDatabase: DatabaseReference? = null
private var query: DatabaseReference = FirebaseDatabase.getInstance()
.reference
.child("users").child("name")
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val currentFirebaseUser = FirebaseAuth.getInstance().currentUser
Toast.makeText(this, "" + currentFirebaseUser!!.uid, Toast.LENGTH_SHORT).show()
val options: FirebaseRecyclerOptions<DataBaseModel> =
FirebaseRecyclerOptions.Builder<DataBaseModel>()
.setQuery(query, DataBaseModel::class.java).build()
recyclerList.layoutManager = LinearLayoutManager(this)
adapter = MyAdapter(options)
recyclerList.adapter = adapter
}
override fun onStart() {
super.onStart()
adapter.startListening()
}
override fun onStop() {
super.onStop()
adapter.stopListening()
}
}
MyAdapter.kt
package com.newhome.smarty
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.recyclerview.widget.RecyclerView
import com.firebase.ui.database.FirebaseRecyclerAdapter
import com.firebase.ui.database.FirebaseRecyclerOptions
class MyAdapter(options: FirebaseRecyclerOptions<DataBaseModel>) :
FirebaseRecyclerAdapter<DataBaseModel, MyAdapter.MyViewHolder>(options) {
class MyViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
var name: TextView = itemView.findViewById(R.id.switchName)
// var finalName:String = name.toString()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val view: View =
LayoutInflater.from(parent.context)
.inflate(R.layout.firebase_switch_layout, parent, false)
return MyViewHolder(view)
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int, model: DataBaseModel) {
// holder.finalName=model.name.toString()
holder.name.text = model.name.toString()
}
}
DataBaseModel.kt
package com.newhome.smarty
class DataBaseModel {
var name: String? = null
constructor()
constructor(name: String?) {
this.name = name
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/recyclerList"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
firebase_swith_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardCornerRadius="15dp">
<androidx.appcompat.widget.AppCompatTextView
android:id="@+id/name"
android:layout_width="364dp"
android:layout_height="77dp"
android:layout_marginLeft="10dp"
android:text="HELLO"
android:gravity="center"/>
</androidx.cardview.widget.CardView>
I also try with java but same error
MainActivity.java
package com.example.smarino;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.os.Bundle;
import com.firebase.ui.database.FirebaseRecyclerOptions;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.Query;
public class MainActivity extends AppCompatActivity {
RecyclerView recyclerView;
// Query query = FirebaseDatabase.getInstance()
// .getReference()
// .child("Users");
MyFirebaseAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recyclerList);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
FirebaseRecyclerOptions<ModelClass> options =
new FirebaseRecyclerOptions.Builder<ModelClass>()
.setQuery(FirebaseDatabase.getInstance()
.getReference()
.child("Users"), ModelClass.class)
.build();
adapter = new MyFirebaseAdapter(options);
recyclerView.setAdapter(adapter);
}
@Override
protected void onStart() {
super.onStart();
adapter.startListening();
}
@Override
protected void onStop() {
super.onStop();
adapter.stopListening();
}
}
MyFirebaseAdapter.java
package com.example.smarino;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import com.firebase.ui.database.FirebaseRecyclerAdapter;
import com.firebase.ui.database.FirebaseRecyclerOptions;
public class MyFirebaseAdapter extends FirebaseRecyclerAdapter<ModelClass, MyFirebaseAdapter.MyViewHolder> {
public MyFirebaseAdapter(@NonNull FirebaseRecyclerOptions options) {
super(options);
}
@NonNull
@Override
public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.firebase_switch_layout, parent, false);
return new MyViewHolder(view);
}
@Override
protected void onBindViewHolder(@NonNull MyViewHolder holder, int position, @NonNull ModelClass model) {
holder.name.setText(model.getName());
}
static class MyViewHolder extends RecyclerView.ViewHolder {
TextView name;
public MyViewHolder(@NonNull View itemView) {
super(itemView);
name = itemView.findViewById(R.id.name);
}
}
}
ModelClass.java
package com.example.smarino;
public class ModelClass {
String name;
ModelClass() {
}
public ModelClass(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
but all the time i am geting same error
error
2021-02-23 18:28:01.341 5774-5774/com.example.smarino E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.smarino, PID: 5774
com.google.firebase.database.DatabaseException: Can't convert object of type java.lang.String to type com.example.smarino.ModelClass
at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.convertBean(CustomClassMapper.java:436)
at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.deserializeToClass(CustomClassMapper.java:232)
at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.convertToCustomClass(CustomClassMapper.java:80)
at com.google.firebase.database.DataSnapshot.getValue(DataSnapshot.java:203)
at com.firebase.ui.database.ClassSnapshotParser.parseSnapshot(ClassSnapshotParser.java:29)
at com.firebase.ui.database.ClassSnapshotParser.parseSnapshot(ClassSnapshotParser.java:15)
at com.firebase.ui.common.BaseCachingSnapshotParser.parseSnapshot(BaseCachingSnapshotParser.java:36)
at com.firebase.ui.common.BaseObservableSnapshotArray.get(BaseObservableSnapshotArray.java:52)
at com.firebase.ui.database.FirebaseRecyclerAdapter.getItem(FirebaseRecyclerAdapter.java:109)
at com.firebase.ui.database.FirebaseRecyclerAdapter.onBindViewHolder(FirebaseRecyclerAdapter.java:149)
at androidx.recyclerview.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:7065)
at androidx.recyclerview.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:7107)
at androidx.recyclerview.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:6012)
at androidx.recyclerview.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:6279)
at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6118)
at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6114)
at androidx.recyclerview.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2303)
at androidx.recyclerview.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1627)
at androidx.recyclerview.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1587)
at androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:665)
at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:4134)
at androidx.recyclerview.widget.RecyclerView.dispatchLayout(RecyclerView.java:3851)
at androidx.recyclerview.widget.RecyclerView.onLayout(RecyclerView.java:4404)
at android.view.View.layout(View.java:22105)
at android.view.ViewGroup.layout(ViewGroup.java:6290)
at androidx.constraintlayout.widget.ConstraintLayout.onLayout(ConstraintLayout.java:1855)
at android.view.View.layout(View.java:22105)
at android.view.ViewGroup.layout(ViewGroup.java:6290)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
at android.view.View.layout(View.java:22105)
at android.view.ViewGroup.layout(ViewGroup.java:6290)
at androidx.appcompat.widget.ActionBarOverlayLayout.onLayout(ActionBarOverlayLayout.java:530)
at android.view.View.layout(View.java:22105)
at android.view.ViewGroup.layout(ViewGroup.java:6290)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
at android.view.View.layout(View.java:22105)
at android.view.ViewGroup.layout(ViewGroup.java:6290)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1829)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1673)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1582)
at android.view.View.layout(View.java:22105)
at android.view.ViewGroup.layout(ViewGroup.java:6290)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
at com.android.internal.policy.DecorView.onLayout(DecorView.java:786)
at android.view.View.layout(View.java:22105)
2021-02-23 18:28:01.341 5774-5774/com.example.smarino E/AndroidRuntime: at android.view.ViewGroup.layout(ViewGroup.java:6290)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:3356)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2827)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1940)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:8041)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:1163)
at android.view.Choreographer.doCallbacks(Choreographer.java:986)
at android.view.Choreographer.doFrame(Choreographer.java:902)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:1148)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7710)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
pleas help me
thanks
Source: Android Questions
