This is my Quiz App project for the Grow With Google Challenge Scholarship: Android Basics Course

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
    <android.support.v4.widget.NestedScrollView
    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"
    android:fillViewport="true"
    tools:context="com.example.android.braquizapp.MainActivity">

<android.support.constraint.ConstraintLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <!--Question 1. Radio button selection.-->

    <TextView
        android:id="@+id/questionOne"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="8dp"
        android:text="@string/question_One"
        android:textSize="16sp"
        app:layout_constraintLeft_toLeftOf="parent" />

    <RadioGroup
        android:id="@+id/radioQuestionOne"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        app:layout_constraintTop_toBottomOf="@+id/questionOne">

        <RadioButton
            android:id="@+id/radio_button_a"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/qOne1"
            android:textSize="14sp"
            android:onClick="onRadioButtonClicked"/>
        <RadioButton
            android:id="@+id/correct_radio_button_b"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/qOne2"
            android:textSize="14sp"
            android:onClick="onRadioButtonClicked" />
        <RadioButton
            android:id="@+id/radio_button_c"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/qOne3"
            android:textSize="14sp"
            android:onClick="onRadioButtonClicked" />

    </RadioGroup>

    <!--Question 2. Checkbox selection.-->

    <TextView
        android:id="@+id/questionTwo"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="8dp"
        android:layout_marginTop="8dp"
        android:text="@string/question_Two"
        android:textSize="16sp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/radioQuestionOne" />

    <CheckBox
        android:id="@+id/correct_qTwoA"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qT1"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/questionTwo"/>

    <CheckBox
        android:id="@+id/correct_qTwoB"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qT2"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/correct_qTwoA"/>

    <CheckBox
        android:id="@+id/correct_qTwoC"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qT3"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/correct_qTwoB"/>

    <CheckBox
        android:id="@+id/qTwoD"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qT4"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/correct_qTwoC"/>

    <CheckBox
        android:id="@+id/qTwoE"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qT5"
        android:textSize="14sp"
        app:layout_constraintTop_toBottomOf="@+id/qTwoD"/>

    <CheckBox
        android:id="@+id/correct_qTwoF"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qT6"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/qTwoE"/>

    <!--Question 3. Checkbox selection.-->

    <TextView
        android:id="@+id/questionThree"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="8dp"
        android:layout_marginTop="8dp"
        android:text="@string/question_Three"
        android:textSize="16sp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/correct_qTwoF" />

    <CheckBox
        android:id="@+id/correct_qThrA"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qThree1"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/questionThree"/>

    <CheckBox
        android:id="@+id/correct_qThrB"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qThree2"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/correct_qThrA"/>

    <CheckBox
        android:id="@+id/correct_qThrC"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qThree3"
        android:textSize="14sp"
        android:onClick="onCheckBoxClicked"
        app:layout_constraintTop_toBottomOf="@+id/correct_qThrB"/>

    <CheckBox
        android:id="@+id/qThrD"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="8dp"
        android:text="@string/qThree4"
        android:textSize="14sp"
        app:layout_constraintTop_toBottomOf="@+id/correct_qThrC"/>

    <!--Question 4. Radio button selection.-->

    <TextView
        android:id="@+id/questionFour"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="8dp"
        android:text="@string/question_Four"
        android:textSize="16sp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/qThrD" />

    <RadioGroup
        android:id="@+id/radioQuestionFour"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        app:layout_constraintTop_toBottomOf="@+id/questionFour">

        <RadioButton
            android:id="@+id/correct_yes_radio_button4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/Si"
            android:textSize="14sp"
            android:onClick="onRadioButtonClicked" />
        <RadioButton
            android:id="@+id/no_radio_button4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/No"
            android:textSize="14sp"
            android:onClick="onRadioButtonClicked" />

    </RadioGroup>

    <!--Question 5. Radio button selection.-->

    <TextView
        android:id="@+id/questionFive"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="8dp"
        android:text="@string/question_Five"
        android:textSize="16sp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/radioQuestionFour" />

    <RadioGroup
        android:id="@+id/radioQuestionFive"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        app:layout_constraintTop_toBottomOf="@+id/questionFive">

        <RadioButton
            android:id="@+id/yes_radio_button5"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/Si"
            android:textSize="14sp"
            android:onClick="onRadioButtonClicked" />
        <RadioButton
            android:id="@+id/correct_no_radio_button5"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/No"
            android:textSize="14sp"
            android:onClick="onRadioButtonClicked" />

    </RadioGroup>

    <TextView
        android:id="@+id/yourGrade"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="8dp"
        android:layout_marginTop="8dp"
        android:text="Your grade will be posted here after you click on the button."
        android:textSize="16sp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/radioQuestionFive" />

    <LinearLayout
        android:id="@+id/nameTextInput"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        app:layout_constraintTop_toBottomOf="@+id/yourGrade">

        <EditText
            android:id="@+id/name_field"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Your Name"
            android:inputType="textCapWords" />

    </LinearLayout>

    <LinearLayout
        android:id="@+id/linearLayoutButtons"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_marginTop="8dp"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/nameTextInput">

        <Button
            android:id="@+id/gradeQuiz"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="8dp"
            android:text="Grade Quiz"
            android:onClick="gradeQuiz"/>

        <Button
            android:id="@+id/btnPlus"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="8dp"
            android:text="Submit Grade"
            android:onClick="submitGrade"
            app:layout_constraintLeft_toLeftOf="parent" />

    </LinearLayout>

</android.support.constraint.ConstraintLayout>

</android.support.v4.widget.NestedScrollView>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.android.braquizapp">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

colors.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#3F51B5</color>
    <color name="colorPrimaryDark">#303F9F</color>
    <color name="colorAccent">#FF4081</color>
</resources>

MainActivity.java

package com.example.android.braquizapp;

import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.TextView;
import android.widget.Toast;

import java.lang.reflect.Method;

public class MainActivity extends AppCompatActivity {

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

    int counterQ1 = 0;
    int counterQ2 = 0;
    int counterQ3 = 0;
    int counterQ4 = 0;
    int counterQ5 = 0;
    int totalGrade;

    public void onCheckBoxClicked (View view){
        // Is the check box now checked?
        boolean checked = ((CheckBox) view).isChecked();
        // Add 1 point for each correct answer selected.
        CheckBox correctAnswerTwoA = (CheckBox) findViewById(R.id.correct_qTwoA);
        CheckBox correctAnswerTwoB = (CheckBox) findViewById(R.id.correct_qTwoB);
        CheckBox correctAnswerTwoC = (CheckBox) findViewById(R.id.correct_qTwoC);
        CheckBox correctAnswerTwoF = (CheckBox) findViewById(R.id.correct_qTwoF);

        CheckBox correctAnswerThreeA = (CheckBox) findViewById(R.id.correct_qThrA);
        CheckBox correctAnswerThreeB = (CheckBox) findViewById(R.id.correct_qThrB);
        CheckBox correctAnswerThreeC = (CheckBox) findViewById(R.id.correct_qThrC);

        // Which check box was checked?
        switch(view.getId()) {
//      Question 2: A, B, C, F are correct answers, add 1 point to total grade.
            case R.id.correct_qTwoA:
                if (checked) {
                    correctAnswerTwoA.setChecked(true);
                    Toast.makeText(this, "Yes! You got it right!", Toast.LENGTH_LONG).show();
                    counterQ2 = 1;
                }
                break;

            case R.id.correct_qTwoB:
                if (checked) {
                    correctAnswerTwoB.setChecked(true);
                    Toast.makeText(this, "Yes! You got it right!", Toast.LENGTH_LONG).show();
                    counterQ2 = counterQ2 + 1;
                }
                break;

            case R.id.correct_qTwoC:
                if (checked) {
                    correctAnswerTwoC.setChecked(true);
                    Toast.makeText(this, "Yes! You got it right!", Toast.LENGTH_LONG).show();
                    counterQ2 = counterQ2 + 1;
                }
                break;

            case R.id.correct_qTwoF:
                if (checked) {
                    correctAnswerTwoF.setChecked(true);
                    Toast.makeText(this, "Yes! You got it right!", Toast.LENGTH_LONG).show();
                    counterQ2 = counterQ2 + 1;
                }
                break;

            case R.id.qTwoD:
                if (checked) {
                    ((CheckBox) view).setChecked(true);
                    Toast.makeText(this, "Nope...  try again!", Toast.LENGTH_SHORT).show();
                }
                break;

//      Question 3: A, B, C are correct answers, add 1 point to total grade.
            case R.id.correct_qThrA:
                if (checked) {
                    correctAnswerThreeA.setChecked(true);
                    Toast.makeText(this, "Yes! You got it right!", Toast.LENGTH_LONG).show();
                    counterQ3 = 1;
                }
                break;

            case R.id.correct_qThrB:
                if (checked) {
                    correctAnswerThreeB.setChecked(true);
                    Toast.makeText(this, "Yes! You got it right!", Toast.LENGTH_LONG).show();
                    counterQ3 = counterQ3 + 1;
                }
                break;

            case R.id.correct_qThrC:
                if (checked) {
                    correctAnswerThreeC.setChecked(true);
                    Toast.makeText(this, "Yes! You got it right!", Toast.LENGTH_LONG).show();
                    counterQ3 = counterQ3 + 1;
                }
                break;
        }
    }

    public void onRadioButtonClicked(View view) {
        // Is the button now checked?
        boolean checked = ((RadioButton) view).isChecked();
        // Add 1 point for each correct answer selected.
        RadioButton correctAnswerOne = (RadioButton) findViewById(R.id.correct_radio_button_b);
        RadioButton correctAnswerFour = (RadioButton) findViewById(R.id.correct_yes_radio_button4);
        RadioButton correctAnswerFive = (RadioButton) findViewById(R.id.correct_no_radio_button5);

        // Which radio button was clicked?
        switch(view.getId()) {
//      Question 1
            case R.id.radio_button_a:
                if (checked) {
                    ((RadioButton) view).setChecked(true);
                    Toast.makeText(this, "Nope...  try again!", Toast.LENGTH_SHORT).show();
                    if (counterQ1 == 1) {
                        // no point
                        counterQ1 = 0;
                    }
                }
                break;

            case R.id.radio_button_c:
                if (checked) {
                    ((RadioButton) view).setChecked(true);
                    Toast.makeText(this, "Nope...  try again!", Toast.LENGTH_SHORT).show();
                    if (counterQ1 == 1) {
                        // no point
                        counterQ1 = 0;
                    }
                }
                break;

            case R.id.correct_radio_button_b:
                if (checked) {
                    correctAnswerOne.setChecked(true);
                    counterQ1 = 1;
               }
                break;

//      Question 4
            case R.id.no_radio_button4:
                if (checked) {
                    ((RadioButton) view).setChecked(true);
                    if (counterQ4 == 1) {
                        // no point
                        counterQ4 = 0;
                    }
                }
                break;

            case R.id.correct_yes_radio_button4:
                if (checked) {
                    correctAnswerFour.setChecked(true);
                    Toast.makeText(this, "You got it!", Toast.LENGTH_SHORT).show();
                    counterQ4 = 1;
                }
                break;

//      Question 5
            case R.id.yes_radio_button5:
                if (checked) {
                    ((RadioButton) view).setChecked(true);
                    if (counterQ5 == 1) {
                        // no point
                        counterQ5 = 0;
                    }
                }
                break;

            case R.id.correct_no_radio_button5:
                if (checked) {
                    correctAnswerFive.setChecked(true);
                    Toast.makeText(this, "You got it!", Toast.LENGTH_SHORT).show();
                    counterQ5 = 1;
                }
                break;
        }
        Log.v("MainActivity", "Radio button points so far: "+ counterQ1 + counterQ2 + counterQ3 + counterQ4 + counterQ5);
    }

//    After pressing Grade Quiz button, this method calls createGradeSummary method to get string;
//    then calls displayMessage to display string.
    public void gradeQuiz(View view) {
        EditText nameField = (EditText) findViewById(R.id.name_field);
        String nameInput = nameField.getText().toString();
        totalGrade = calculateGrade(counterQ1, counterQ2, counterQ3, counterQ4, counterQ5);
        String yourGradeMessage = createGradeSummary (nameInput, totalGrade, counterQ1, counterQ2, counterQ3, counterQ4, counterQ5);
        displayMessage(yourGradeMessage);
    }

    private int calculateGrade(int counterQ1, int counterQ2, int counterQ3, int counterQ4, int counterQ5) {
        int calcGrade = counterQ1 + counterQ2 + counterQ3 + counterQ4 + counterQ5;
        return calcGrade;
    }

    //    Returns score total and breakdown in a string.
    private String createGradeSummary(String nameField, int totalGrade, int counterQ1, int counterQ2, int counterQ3, int counterQ4, int counterQ5) {
        return nameField + ", this is your total score: " + totalGrade + "\nTotal score breakdown:" + "\nQuestion 1: " + counterQ1 +
                "\nQuestion 2: " + counterQ2 + "\nQuestion 3: " + counterQ3 + "\nQuestion 4: " + counterQ4 + "\nQuestion 5: " + counterQ5;
    }

    private void displayMessage(String message) {
        TextView yourGradeTextView = (TextView) findViewById(R.id.yourGrade);
        yourGradeTextView.setText(message);
    }
    public void submitGrade(View view){
        EditText nameField = (EditText) findViewById(R.id.name_field);
        String nameInput = nameField.getText().toString();
        totalGrade = calculateGrade(counterQ1, counterQ2, counterQ3, counterQ4, counterQ5);
        String yourGradeMessage = createGradeSummary (nameInput, totalGrade, counterQ1, counterQ2, counterQ3, counterQ4, counterQ5);

        Intent intent = new Intent (Intent.ACTION_SENDTO);
        intent.setData(Uri.parse ("mailto: "));
        intent.putExtra(Intent.EXTRA_SUBJECT, "Your BraQuiz Score");
        intent.putExtra(Intent.EXTRA_TEXT, yourGradeMessage);
        if (intent.resolveActivity(getPackageManager()) != null) {
            startActivity(intent);
        }
    }
}

strings.xml

<resources>
    <string name="app_name">Brassiere History Trivia App</string>
    <!--<string name="title_header">How much you know about brassieres?</string>-->

    <string name="question_One">\n1. Bandeau is ... [chose one]</string>
    <string name="qOne1">a popular 80s new wave band.</string>
    <string name="qOne2">worn to cover breasts.</string>
    <string name="qOne3">an island off coast of France.</string>

    <string name="question_Two">2. Corsets … </string>
    <string name="qT1">were used in the early 1500s in France.</string>
    <string name="qT2">are made with a whalebone sewn into it.</string>
    <string name="qT3">flattened and pushed women\'s breasts upward.</string>
    <string name="qT4">are extremely comfortable.</string>
    <string name="qT5">were adapted by African tribes in 1600s.</string>
    <string name="qT6">were popular until the early 1900s.</string>

    <string name="question_Three">3. Girdles ... </string>
    <string name="qThree1">were first used in late 19th century.</string>
    <string name="qThree2">forces the torso forward and the hips to jut outward.</string>
    <string name="qThree3">can make a woman’s figure more of an "S" shape.</string>
    <string name="qThree4">can make some figures into a “C” shape.</string>

    <string name="question_Four">4. In 1911, “Brassiere” was added to the Oxford English Dictionary.</string>

    <string name="question_Five">5. Brasserie is misspelled in this app.</string>

    <string name="Si">True</string>
    <string name="No">False</string>

    <string name="toast_Five">Nope. Brasserie is French for "brewery”.  Brassiere is spelled correctly.</string>

</resources>

styles.xml

<resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">#e91e63</item>
        <item name="colorPrimaryDark">#ad1457</item>
        <item name="colorAccent">#f06292</item>
    </style>

</resources>