'Recyclerview not call any Adapter method: onCreateViewHolder, onBindViewHolder
Here are my codes for MyAdapter, ActivityMain, MinActivity, and User
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
Context context;
ArrayList<User> list;
public MyAdapter(Context context, ArrayList<User> list) {
this.context = context;
this.list = list;
}
@NonNull
@Override
public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(context).inflate(R.layout.item, parent, false);
return new MyViewHolder(v);
}
@Override
public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
// here is the problem that I don't know how to fix][1]
// I'm tryin to pass data from firebase to Recyclerview
// error I'm getting here is:
// [Cannot resolve method 'getFirstName' in 'User'
// Cannot resolve method 'getLastName' in 'User'
// Cannot resolve method 'getAge' in 'User']
User user = list.get(position);
holder.FirstName.setText(user.getFirstName());
holder.LastName.setText(user.getLastName());
holder.Age.setText(user.getAge());
}
@Override
public int getItemCount() {
return list.size();
}
public static class MyViewHolder extends RecyclerView.ViewHolder{
TextView FirstName, LastName, Age;
public MyViewHolder(@NonNull View itemView) {
super(itemView);
FirstName = itemView.findViewById(R.id.tvFirstName);
LastName = itemView.findViewById(R.id.tvLastName);
Age = itemView.findViewById(R.id.tvAge);
}
}
}
This is MainActivity code
public class MainActivity extends AppCompatActivity {
RecyclerView recyclerView;
DatabaseReference database;
MyAdapter myAdapter;
ArrayList<User> list;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_Main);
recyclerView = findViewById(R.id.userList);
database = FirebaseDatabase.getInstance().getReference("User");
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
list = new ArrayList<>();
myAdapter = new MyAdapter(this,list);
recyclerView.setAdapter(myAdapter);
database.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
for (DataSnapshot dataSnapshot : snapshot.getChildren()){
User user = dataSnapshot.getValue(User.class);
list.add(user);
}
myAdapter.notifyDataSetChanged();
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
}
}
This is User codes which I generated with getter
public class User {
String FirstName, LastName, Age;
public String getFirstName() {
return FirstName;
}
public String getLastName() {
return LastName;
}
public String getAge() {
return Age;
}
{
}
}
This is my layout file
<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
app:cardElevation="8dp"
app:cardCornerRadius="8dp"
android:layout_margin="16dp">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:orientation="vertical">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:orientation="horizontal">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="First Name :"
android:textColor="@color/black"
android:textSize="26sp"
android:textStyle="bold"/>
<TextView
android:id="@+id/tvFirstName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="8dp"
android:text="Arya"
android:textColor="@color/black"
android:textSize="20sp" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:orientation="horizontal">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/last_name"
android:textColor="@color/black"
android:textSize="26sp"
android:textStyle="bold"/>
<TextView
android:id="@+id/tvLastName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:text="@string/stark"
android:textColor="@color/black"
android:textSize="20sp" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:orientation="horizontal">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/age"
android:textColor="@color/black"
android:textSize="26sp"
android:textStyle="bold"/>
<TextView
android:id="@+id/tvAge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="8dp"
android:text="18"
android:textColor="@color/black"
android:textSize="20sp" />
</LinearLayout>
</LinearLayout>
</androidx.cardview.widget.CardView>
When I hit RUN it gives me this error:
I'm new to coding.
Solution 1:[1]
you can change your code like this
holder.FirstName.setText(list.getFirstName().get(position));
holder.LastName.setText(list.getLastName().get(position));
holder.Age.setText(list.getAge().get(position);
and you should change this code position
myAdapter = new MyAdapter(this,list);
recyclerView.setAdapter(myAdapter);
into under this code
database.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
for (DataSnapshot dataSnapshot : snapshot.getChildren()){
User user = dataSnapshot.getValue(User.class);
list.add(user);
}
myAdapter.notifyDataSetChanged();
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
hope it can solve your problem :)
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | Fakhri Khairi |