I want to store my data in Realm database in Android Studio but it is not working - realm

Question

I want to store my data in realm but it is not working, it show me error when I click on save button where I add toast. There is no error found, but data is not saving.
My MainActivity Class
package com.deitel.realmrecyclerviewspinnerpriority;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.Toast;
import com.deitel.realmrecyclerviewspinnerpriority.Modelclass.ModelClass;
import io.realm.Realm;
public class MainActivity extends AppCompatActivity {
private static final String TAG="MainActivity";
Realm realm;
EditText text_name;
EditText text_details;
Button btn_save;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
realm=Realm.getDefaultInstance();
Realm.init(getApplicationContext());
text_name = findViewById(R.id.text_name);
text_details = findViewById(R.id.text_details);
btn_save.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
savedata(text_name.getText().toString(),text_details.getText().toString());
}
});
}
private void savedata(final String name, final String datails){
realm.executeTransactionAsync(new Realm.Transaction() {
#Override
public void execute(Realm bgrealm) {
// Number maxid=bgrealm.where(ModelClass.class).max("id");
// int newkey=(maxid==null) ? 1 : maxid.intValue()+1;
ModelClass user = bgrealm.createObject(ModelClass.class);
user.setName(name);
user.setDetails(datails);
}
}, new Realm.Transaction.OnSuccess() {
#Override
public void onSuccess() {
Toast.makeText(MainActivity.this, "success", Toast.LENGTH_SHORT).show();
}
}, new Realm.Transaction.OnError() {
#Override
public void onError(Throwable error) {
Toast.makeText(MainActivity.this, "Error", Toast.LENGTH_SHORT).show();
}
});
}
}
Realm Class Where I initilize configutation etc.
package com.deitel.realmrecyclerviewspinnerpriority;
import android.app.Application;
import io.realm.Realm;
import io.realm.RealmConfiguration;
public class MyApplication extends Application {
#Override
public void onCreate() {
super.onCreate();
Realm.init(this);
RealmConfiguration configuration=new RealmConfiguration.Builder().name("RealmData.realm").build();
Realm.setDefaultConfiguration(configuration);
}
}
Model Class.
package com.deitel.realmrecyclerviewspinnerpriority.Modelclass;
import io.realm.RealmObject;
import io.realm.annotations.PrimaryKey;
public class ModelClass extends RealmObject {
#PrimaryKey
private String Name;
private String Details;
public String getName() {
return Name;
}
public void setName(String name) {
Name = name;
}
public String getDetails() {
return Details;
}
public void setDetails(String details) {
Details = details;
}
}

Answer 1

I think you are not setting primary key,
Try below approach
private void savedata(final String name, final String datails){
try(Realm mRealm = Realm.getDefaultInstance()){
ModelClass user = new ModelClass();
int newkey=(maxid==null) ? 1 : maxid.intValue()+1;
user.setId(newkey);
user.setName(name);
user.setDetails(datails);
mRealm.executeTransaction(rlm-> {
rlm.insertOrUpdate(user);
});
}
}
insertOrUpdate inserts a new record if PK doesn't exists else update it.