English Grammar Test APP ( Admob + Android Studio)

Introduction

In this tutorial, we will be creating a complete English Grammar Test APP using Admob and Android Studio. The app will be designed to test users' knowledge of English grammar, with multiple-choice questions and a scoring system. We will also be integrating Admob ads to monetize the app and earn revenue.

Step 1: Setting up the Project in Android Studio

To start, open Android Studio and create a new project. Choose "Empty Activity" as the project template and name it "English Grammar Test".

• Set the package name to "com.example.englishgrammartest"
• Set the language to "Java" (or "Kotlin" if you prefer)
• Set the minimum SDK to "API 16: Android 4.1 (Jelly Bean)"
• Click "Finish" to create the project

Step 2: Designing the User Interface

Next, we need to design the user interface for our app. Open the activity_main.xml file and replace the existing code with the following:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <TextView
        android:id="@+id/question_text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="24sp"
        android:textStyle="bold" />

    <RadioGroup
        android:id="@+id/answer_group"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <RadioButton
            android:id="@+id/option1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="18sp" />

        <RadioButton
            android:id="@+id/option2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="18sp" />

        <RadioButton
            android:id="@+id/option3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="18sp" />

        <RadioButton
            android:id="@+id/option4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="18sp" />

    </RadioGroup>

    <Button
        android:id="@+id/submit_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Submit" />

    <TextView
        android:id="@+id/score_text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="18sp" />

</LinearLayout>

This design includes a text view for displaying the question, a radio group for selecting the answer, a submit button, and a text view for displaying the score.

Step 3: Creating the Questions and Answers

Next, we need to create an array of questions and answers. Create a new Java class called "Questions.java" and add the following code:

public class Questions {
    private String[] questions = {
        "What is the present tense of the verb 'to go'?",
        "What is the past tense of the verb 'to eat'?",
        "What is the future tense of the verb 'to study'?"
    };

    private String[][] answers = {
        {"go", "goes", "gone", "going"},
        {"eat", "eats", "ate", "eating"},
        {"study", "studies", "studied", "studying"}
    };

    public String[] getQuestions() {
        return questions;
    }

    public String[][] getAnswers() {
        return answers;
    }
}

This class contains an array of questions and an array of answers, where each answer is an array of possible answers.

Step 4: Implementing the Logic for the Quiz

Next, we need to implement the logic for the quiz. Create a new Java class called "QuizActivity.java" and add the following code:

public class QuizActivity extends AppCompatActivity {
    private Questions questions;
    private int currentQuestionIndex;
    private int score;

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

        questions = new Questions();
        currentQuestionIndex = 0;
        score = 0;

        TextView questionText = findViewById(R.id.question_text);
        RadioGroup answerGroup = findViewById(R.id.answer_group);
        Button submitButton = findViewById(R.id.submit_button);
        TextView scoreText = findViewById(R.id.score_text);

        questionText.setText(questions.getQuestions()[currentQuestionIndex]);
        answerGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                RadioButton selectedRadioButton = findViewById(checkedId);
                if (selectedRadioButton.getText().equals(questions.getAnswers()[currentQuestionIndex][0])) {
                    score++;
                }
                currentQuestionIndex++;
                if (currentQuestionIndex < questions.getQuestions().length) {
                    questionText.setText(questions.getQuestions()[currentQuestionIndex]);
                } else {
                    scoreText.setText("Your score is " + score + " out of " + questions.getQuestions().length);
                }
            }
        });

        submitButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                answerGroup.clearCheck();
            }
        });
    }
}

This class implements the logic for the quiz, including displaying the questions, checking the answers, and updating the score.

Step 5: Adding Admob Ads

To add Admob ads to our app, we need to create a new file called "admob.xml" in the res/values directory:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="admob_app_id">YOUR_APP_ID</string>
    <string name="admob_banner_ad_unit_id">YOUR_BANNER_AD_UNIT_ID</string>
    <string name="admob_interstitial_ad_unit_id">YOUR_INTERSTITIAL_AD_UNIT_ID</string>
</resources>

Replace "YOUR_APP_ID", "YOUR_BANNER_AD_UNIT_ID", and "YOUR_INTERSTITIAL_AD_UNIT_ID" with your actual Admob app ID and ad unit IDs.

Next, we need to add the Admob SDK to our project. Add the following code to the build.gradle file:

dependencies {
    implementation 'com.google.android.gms:play-services-ads:19.4.0'
}

Finally, we need to add the Admob ads to our app. Open the activity_main.xml file and add the following code:

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <!-- Your layout code here -->

    <com.google.android.gms.ads.AdView
        android:id="@+id/adView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        ads:adSize="BANNER"
        ads:adUnitId="@string/admob_banner_ad_unit_id" />

</LinearLayout>

This code adds a banner ad to the bottom of the screen.

Step 6: Testing the App

Finally, we need to test the app to make sure it works correctly. Run the app on an emulator or a physical device and test the quiz functionality. Make sure the questions and answers are displayed correctly, and the score is updated correctly.

That's it! We have now created a complete English Grammar Test APP using Admob and Android Studio.