You are adding an extra space in front when next button is clicked. Either remove the space by using trim() method.

String answer = answerText.getText().toString().trim();

or use setText("") instead of setText(" ").

I have a simple app which generates a random String and display it as a TextView. It replaces the letters with their transliterations. If the user types the correct transliteration, it prints “That’s correct” otherwise it prints “Not exactly, it’s: ” + the correct transliteration. However, it works correctly just for the first time. After that, even when the user types the correct transliteration it says: “Not exactly, it’s:”.
By printing the answer, I checked if it detects the user input correctly; It does but it still doesn’t work. I’m not sure which part of my code makes trouble.
I’d appreciate any help.

Here is a simple form of my MainActivity:

package com.example.test;

import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import androidx.annotation.RequiresApi;
import androidx.appcompat.app.AppCompatActivity;
import java.util.Random;

//Letter activity

public class MainActivity extends AppCompatActivity {

    String wordStr;
    TextView resultTextView;
    EditText answerText;
    String result;
    TextView randomText;

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

        resultTextView = (TextView) findViewById(R.id.result);
        answerText = (EditText) findViewById(R.id.answer);
        randomText = (TextView) findViewById(R.id.randomText);

        findViewById(R.id.newBtn).setOnClickListener(buttonClickListener);
        findViewById(R.id.check).setOnClickListener(buttonClickListener);
        generateRandomStr();
    }

    //generates random word

    public void generateRandomStr(){

        String Chars = "Бд";
        StringBuilder word = new StringBuilder();
        Random rnd = new Random();
        while (word.length() < 3) {
            int index = (int) (rnd.nextFloat() * Chars.length());
            word.append(Chars.charAt(index));
        }

        wordStr = word.toString();
        randomText.setText(wordStr);
    }


    private  View.OnClickListener buttonClickListener = new View.OnClickListener() {
        @RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
        @Override
        public void onClick(View view) {

            switch (view.getId()) {
                //Check button
                case R.id.check:

                    String answer = answerText.getText().toString();
                    String transliteration = wordStr.replace("Б", "b").replace("д", "d");
                    if (answer.equals(transliteration)) {
                        result = "That's correct";
                    } else {
                        result = "Not exactly, it's actually:" + " " + transliteration;
                    }
                    resultTextView.setText(result + " ");

                    break;
                //New button
                case R.id.newBtn:

                    resultTextView.setText(" ");
                    answerText.setText(" ");
                    generateRandomStr();
                    break;

            }
        }
    };
}

And here is 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">

    <Button
        android_id="@+id/newBtn"
        android_layout_width="wrap_content"
        android_layout_height="wrap_content"
        android_text="New"
        android_textSize="18sp"
        app_layout_constraintBottom_toBottomOf="parent"
        app_layout_constraintEnd_toEndOf="parent"
        app_layout_constraintHorizontal_bias="0.682"
        app_layout_constraintStart_toStartOf="parent"
        app_layout_constraintTop_toTopOf="parent"
        app_layout_constraintVertical_bias="0.528" />

    <Button
        android_id="@+id/check"
        android_layout_width="wrap_content"
        android_layout_height="wrap_content"
        android_text="Check"
        android_textSize="18sp"
        app_layout_constraintBottom_toBottomOf="parent"
        app_layout_constraintEnd_toEndOf="parent"
        app_layout_constraintHorizontal_bias="0.314"
        app_layout_constraintStart_toStartOf="parent"
        app_layout_constraintTop_toTopOf="parent"
        app_layout_constraintVertical_bias="0.528" />

    <TextView
        android_id="@+id/randomText"
        android_layout_width="wrap_content"
        android_layout_height="wrap_content"
        android_text="TextView"
        android_textSize="36sp"
        app_layout_constraintBottom_toBottomOf="parent"
        app_layout_constraintEnd_toEndOf="parent"
        app_layout_constraintHorizontal_bias="0.498"
        app_layout_constraintStart_toStartOf="parent"
        app_layout_constraintTop_toTopOf="parent"
        app_layout_constraintVertical_bias="0.136" />

    <EditText
        android_id="@+id/answer"
        android_layout_width="wrap_content"
        android_layout_height="wrap_content"
        android_ems="10"
        android_inputType="textPersonName"
        app_layout_constraintBottom_toBottomOf="parent"
        app_layout_constraintEnd_toEndOf="parent"
        app_layout_constraintHorizontal_bias="0.497"
        app_layout_constraintStart_toStartOf="parent"
        app_layout_constraintTop_toTopOf="parent"
        app_layout_constraintVertical_bias="0.371" />

    <TextView
        android_id="@+id/result"
        android_layout_width="wrap_content"
        android_layout_height="wrap_content"
        android_text="Result"
        android_textSize="24sp"
        app_layout_constraintBottom_toBottomOf="parent"
        app_layout_constraintEnd_toEndOf="parent"
        app_layout_constraintStart_toStartOf="parent"
        app_layout_constraintTop_toTopOf="parent"
        app_layout_constraintVertical_bias="0.726" />
</androidx.constraintlayout.widget.ConstraintLayout>

Thanks in advance