Why is the Android app crashing?

Question

Java

Hello. For some reason, when you click on the send message button, the chat crashes, which I do according to the tutorial. Can you suggest a reason? Thanks in advance.

package Karasik.com;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.TextView;
import com.firebase.ui.auth.AuthUI;
import com.firebase.ui.database.FirebaseListAdapter;
import com.firebase.ui.database.FirebaseListOptions;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.FirebaseDatabase;
import android.text.format.DateFormat;

public class MainActivity extends AppCompatActivity {

private static int SIGN_IN_CODE=1;
private RelativeLayout activity_main;
private FirebaseListAdapter<Message> adapter;
private FloatingActionButton sendBtn;

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if(requestCode==SIGN_IN_CODE) {
           if(requestCode == RESULT_OK) {
               Snackbar.make(activity_main, "Вы авторизованы", Snackbar.LENGTH_LONG).show();
               displayAllMessages();
               } else {
                 Snackbar.make(activity_main, "Вы не авторизованы", Snackbar.LENGTH_LONG).show();
                 finish();
           }
        }
    }

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

        activity_main=findViewById(R.id.activity_main);
        sendBtn = findViewById(R.id.btnSend);
        sendBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                EditText textField = findViewById(R.id.messageField);
                if(textField.getText().toString().equals(""))
                    return;
                FirebaseDatabase.getInstance().getReference().push().setValue(new Message(FirebaseAuth.getInstance().getCurrentUser().getEmail(), textField.getText().toString()));
                textField.setText("");
            }
        });

        //Пользователь ещё не авторизован
        if (FirebaseAuth.getInstance().getCurrentUser()==null)
            startActivityForResult(AuthUI.getInstance().createSignInIntentBuilder().build(), SIGN_IN_CODE);
        //Пользователь авторизован
        else {
            Snackbar.make(activity_main, "Вы авторизованы", Snackbar.LENGTH_LONG).show();
            displayAllMessages();
        }
    }

    private void displayAllMessages() {
        ListView listOfMessages = findViewById(R.id.list_of_messages);
        FirebaseListOptions<Message> options =
                new FirebaseListOptions.Builder<Message>()
                        .setQuery(FirebaseDatabase.getInstance().getReference(), Message.class)
                        .setLayout(R.layout.list_item)
                        .build();
        adapter = new FirebaseListAdapter<Message>(options){
            @Override
            protected void populateView(View v, Message model, int position) {
                TextView mess_user, mess_time, mess_text;
                mess_user = v.findViewById(R.id.message_user);
                mess_time = v.findViewById(R.id.message_time);
                mess_text = v.findViewById(R.id.message_text);

                mess_user.setText(model.getUserName());
                mess_text.setText(model.getTextMessage());
                mess_time.setText(DateFormat.format("dd-MM-yyyy HH:mm:ss", model.getMessageTime()));
            }
        };
        listOfMessages.setAdapter(adapter);
    }
}

UPD (Errors from Logcat):

2020-05-16 21:40:40.300 10709-10709/? E/Karasik.com: Unknown bits set in runtime_flags: 0x8000
...
2020-05-16 21:40:42.674 10709-10753/Karasik.com E/eglCodecCommon: glUtilsParamSize: unknow param 0x000082da
2020-05-16 21:40:42.674 10709-10753/Karasik.com E/eglCodecCommon: glUtilsParamSize: unknow param 0x000082da
...
2020-05-16 21:41:10.452 10709-10709/Karasik.com E/AndroidRuntime: FATAL EXCEPTION: main
    Process: Karasik.com, PID: 10709
    com.google.firebase.database.DatabaseException: Found two getters or fields with conflicting case sensitivity for property: textmessage
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper$BeanMapper.addProperty(com.google.firebase:[email protected]@19.3.0:557)
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper$BeanMapper.<init>(com.google.firebase:[email protected]@19.3.0:488)
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.loadOrCreateBeanMapperForClass(com.google.firebase:[email protected]@19.3.0:329)
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.serialize(com.google.firebase:[email protected]@19.3.0:166)
        at com.google.firebase.database.core.utilities.encoding.CustomClassMapper.convertToPlainJavaTypes(com.google.firebase:[email protected]@19.3.0:60)
        at com.google.firebase.database.DatabaseReference.setValueInternal(com.google.firebase:[email protected]@19.3.0:282)
        at com.google.firebase.database.DatabaseReference.setValue(com.google.firebase:[email protected]@19.3.0:159)
        at Karasik.com.MainActivity$1.onClick(MainActivity.java:55)
        at android.view.View.performClick(View.java:7125)
        at android.view.View.performClickInternal(View.java:7102)
        at android.view.View.access$3500(View.java:801)
        at android.view.View$PerformClick.run(View.java:27336)
        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:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)

Answer 1

Click on the "run" tab at the bottom of the studio and read what is written in red letters in the footcloth of the log.
Not understood. according to the text of the error. Highlight the first line from the error and Google.