implementation

app/build.gradle

@@ -16,12 +16,18 @@ android {
             proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
         }
     }
+    compileOptions {
+        sourceCompatibility = '1.8'
+        targetCompatibility = '1.8'
+    }
 }
 
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
     implementation 'com.android.support:appcompat-v7:28.0.0'
+    implementation 'com.android.support:recyclerview-v7:28.0.0'
     implementation 'com.android.support.constraint:constraint-layout:1.1.3'
+    implementation  'com.getbase:floatingactionbutton:1.9.1'
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'com.android.support.test:runner:1.0.2'
     androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

app/src/main/AndroidManifest.xml

@@ -16,6 +16,10 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+
+        <activity android:name=".StudentActivity">
+
+        </activity>
     </application>
 
 </manifest>

app/src/main/java/ru/ok/technopolis/students/MainActivity.java

@@ -1,14 +1,78 @@
 package ru.ok.technopolis.students;
 
+
+import android.content.Intent;
+import android.support.annotation.Nullable;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
+import android.support.v7.widget.LinearLayoutManager;
+import android.support.v7.widget.RecyclerView;
+import android.view.View;
+
+import com.getbase.floatingactionbutton.FloatingActionButton;
+import ru.ok.technopolis.students.Repository.StudentDataRepository;
+
+
+public class MainActivity extends AppCompatActivity implements View.OnClickListener {
+
+    private StudentDataRepository studentDataRepository = StudentDataRepository.getInstance();
+    private StudentAdapter studentAdapter;
 
-public class MainActivity extends AppCompatActivity {
 
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(Bundle savedInstanceState)
+    {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
+        setupRecyclerView();
+        setupAddButton();
+    }
+
+    private void setupAddButton()
+    {
+        FloatingActionButton addButton = findViewById(R.id.activity_main__add_button);
+        addButton.setOnClickListener(this);
+    }
+
+    private void setupRecyclerView() {
+        RecyclerView recyclerView = findViewById(R.id.activity_main__recyclerview);
+        studentAdapter = new StudentAdapter (studentDataRepository.studentsOnRepository(), this::onStudentClick);
+        recyclerView.setAdapter(studentAdapter);
+        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
+        recyclerView.setLayoutManager(linearLayoutManager);
+    }
+
+    private void onStudentClick(Student student)
+    {
+        startActivityForResult(new Intent(this, StudentActivity.class).putExtra("Student", student), 2);
+    }
+
+    @Override
+    public void onClick(View v)
+    {
+        startActivityForResult(new Intent(this, StudentActivity.class),1);
     }
 
+    @Override
+    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data)
+    {
+        super.onActivityResult(requestCode, resultCode, data);
+        Student student;
+        switch (resultCode)
+        {
+            case 1:
+                student = (Student) data.getSerializableExtra("NewStudent");
+                studentDataRepository.add(student);
+                break;
+            case 2:
+                student = (Student) data.getSerializableExtra("ModifyStudent");
+                studentDataRepository.edit(student);
+                break;
+            case 3:
+                student = (Student) data.getSerializableExtra("StudentForDelete");
+                studentDataRepository.delete(student);
+                break;
+        }
+        studentAdapter.notifyDataSetChanged();
+    }
 }

app/src/main/java/ru/ok/technopolis/students/Repository/FemalePhotoRepository.java

@@ -0,0 +1,47 @@
+package ru.ok.technopolis.students.Repository;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.Random;
+
+import ru.ok.technopolis.students.R;
+
+public class FemalePhotoRepository implements PhotoRepository {
+    private static final FemalePhotoRepository ourInstance = new FemalePhotoRepository();
+
+    public static FemalePhotoRepository getInstance() {
+        return ourInstance;
+    }
+
+    private List <Integer> femalePhotos;
+
+    private FemalePhotoRepository() {
+        femalePhotos = new ArrayList(){{
+            this.add(R.drawable.female_1);
+            this.add(R.drawable.female_2);
+            this.add(R.drawable.female_3);
+        }};
+    }
+
+
+    @Override
+    public Integer getPhotoInRepository() throws NoSuchElementException {
+        if(femalePhotos.isEmpty()){
+            throw new NoSuchElementException();
+        }
+        int indexFemalePhoto = new Random().nextInt(femalePhotos.size());
+        Integer malePhoto = femalePhotos.get(indexFemalePhoto);
+        femalePhotos.remove(indexFemalePhoto);
+        return malePhoto;
+    }
+
+    @Override
+    public void putPhotoInRepository(Integer photo) {
+        if(photo == null)
+        {
+            throw new NullPointerException();
+        }
+        femalePhotos.add(photo);
+    }
+}

app/src/main/java/ru/ok/technopolis/students/Repository/MalePhotoRepository.java

@@ -0,0 +1,49 @@
+package ru.ok.technopolis.students.Repository;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.Random;
+
+import ru.ok.technopolis.students.R;
+
+public class MalePhotoRepository implements PhotoRepository
+{
+    private static final MalePhotoRepository ourInstance = new MalePhotoRepository();
+
+    private List <Integer> malePhotos;
+
+
+    public static MalePhotoRepository getInstance() {
+        return ourInstance;
+    }
+
+    private MalePhotoRepository() {
+        malePhotos = new ArrayList() {{
+            this.add(R.drawable.male_1);
+            this.add(R.drawable.male_2);
+            this.add(R.drawable.male_3);
+        }};
+    }
+
+
+    @Override
+    public Integer getPhotoInRepository() throws NoSuchElementException{
+        if(malePhotos.isEmpty()){
+            throw new NoSuchElementException();
+        }
+        int indexMalePhoto = new Random().nextInt(malePhotos.size());
+        Integer malePhoto = malePhotos.get(indexMalePhoto);
+        malePhotos.remove(indexMalePhoto);
+        return malePhoto;
+    }
+
+    @Override
+    public void putPhotoInRepository(Integer photo) {
+        if(photo == null)
+        {
+            throw new NullPointerException();
+        }
+        malePhotos.add(photo);
+    }
+}

app/src/main/java/ru/ok/technopolis/students/Repository/PhotoRepository.java

@@ -0,0 +1,7 @@
+package ru.ok.technopolis.students.Repository;
+
+public interface PhotoRepository
+{
+    Integer getPhotoInRepository ();
+    void putPhotoInRepository (Integer photo);
+}

app/src/main/java/ru/ok/technopolis/students/Repository/StudentDataRepository.java

@@ -0,0 +1,58 @@
+package ru.ok.technopolis.students.Repository;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+
+import ru.ok.technopolis.students.Student;
+
+public class StudentDataRepository implements StudentRepository
+{
+    private static final StudentDataRepository ourInstance = new StudentDataRepository();
+
+    public static StudentDataRepository getInstance() {
+        return ourInstance;
+    }
+
+    private List <Student> students;
+
+
+
+    private StudentDataRepository()
+    {
+        students = new ArrayList<>();
+    }
+
+    @Override
+    public List studentsOnRepository()
+    {
+        return students;
+    }
+
+    @Override
+    public void add(Student student)
+    {
+        students.add(student);
+    }
+
+
+    @Override
+    public void delete(Student student)
+    {
+        for(int i = 0; i < students.size(); i++){
+            if (students.get(i).getId().equals(student.getId())){
+                students.remove(i);
+            }
+        }
+    }
+
+    @Override
+    public void edit(Student student) {
+        for(int i = 0; i < students.size(); i++){
+            if(students.get(i).getId().equals(student.getId())){
+                students.get(i).setFirstName(student.getFirstName());
+                students.get(i).setSecondName(student.getSecondName());
+            }
+        }
+    }
+}

app/src/main/java/ru/ok/technopolis/students/Repository/StudentRepository.java

@@ -0,0 +1,14 @@
+package ru.ok.technopolis.students.Repository;
+
+import java.util.List;
+
+import ru.ok.technopolis.students.Student;
+
+public interface StudentRepository
+{
+    List studentsOnRepository();
+
+    void add(Student student);
+    void delete(Student student);
+    void edit(Student student);
+}

app/src/main/java/ru/ok/technopolis/students/Student.java

@@ -1,17 +1,26 @@
 package ru.ok.technopolis.students;
 
-public class Student {
+import java.io.Serializable;
+import java.util.UUID;
+
+public class Student implements Serializable {
 
     private String firstName;
     private String secondName;
     private boolean maleGender;
     private int photo;
+    private UUID id;
 
-    public Student(String firstName, String secondName, boolean maleGender, int photo) {
-        this.firstName = firstName;
-        this.secondName = secondName;
-        this.maleGender = maleGender;
-        this.photo = photo;
+
+
+    public Student()
+    {
+        id = UUID.randomUUID();
+    }
+
+    public UUID getId()
+    {
+        return id;
     }
 
     public String getFirstName() {
@@ -45,4 +54,6 @@ public int getPhoto() {
     public void setPhoto(int photo) {
         this.photo = photo;
     }
+
+
 }