الكود:

   // recyclerview
    implementation 'com.android.support:recyclerview-v7:+'

    //room db
    implementation "android.arch.persistence.room:runtime:1.1.1"
    annotationProcessor "android.arch.persistence.room:compiler:1.1.1"
    
    // android debug database library
    debugImplementation 'com.amitshekhar.android:debug-db:1.0.4'

 

الكود:

import android.arch.persistence.room.Entity;
import android.arch.persistence.room.PrimaryKey;

@Entity
public class Student {

    @PrimaryKey(autoGenerate = true)
    private int id;
    private String name;
    private String major;

    public Student() {

    }

    public Student(int id, String name, String major) {
        this.id = id;
        this.name = name;
        this.major = major;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getMajor() {
        return major;
    }

    public void setMajor(String major) {
        this.major = major;
    }
}

 

الكود:

import android.arch.persistence.room.Dao;
import android.arch.persistence.room.Delete;
import android.arch.persistence.room.Insert;
import android.arch.persistence.room.OnConflictStrategy;
import android.arch.persistence.room.Query;

import com.example.asus.databasedebug.pojo.Student;

import java.util.List;


@Dao
public interface StudentDAO {

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    void insert (Student student);

    @Delete
    void delete (Student student);

    @Query("SELECT * FROM Student")
    List<Student> getAllStudents();

}

 

الكود:

import android.arch.persistence.room.Database;
import android.arch.persistence.room.RoomDatabase;

import com.example.asus.databasedebug.pojo.Student;

@Database(entities = Student.class, version = 1)
public abstract class StudentDB extends RoomDatabase {

    public abstract StudentDAO studentDAO();

}

 

الكود:

import android.arch.persistence.room.Room;
import android.os.AsyncTask;

import com.example.asus.databasedebug.application.DatabaseDebugApplication;
import com.example.asus.databasedebug.pojo.Student;

import java.util.List;


// Singleton
public class StudentRepository {

    // singleton object
    private static StudentRepository repository = new StudentRepository();

    // database object
    private static StudentDB studentDB;

    // constructor
    private StudentRepository(){
        initDB();
    }

    public static StudentRepository getInstance(){
        return repository;
    }

    private void initDB() {
        studentDB = Room.databaseBuilder(DatabaseDebugApplication.getContext(),
                StudentDB.class, "StudentDatabase").build();
    }

    public List<Student> getStudents(){
        try {
            return new DataBaseOperation().execute().get();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    // Async
    class DataBaseOperation extends AsyncTask<Void,Void,List<Student>> {

        @Override
        protected List<Student> doInBackground(Void... voids) {
            return studentDB.studentDAO().getAllStudents();
        }
    }
}

 

الكود:

import android.app.Application;
import android.content.Context;

public class DatabaseDebugApplication extends Application {

    private static Context context;

    @Override
    public void onCreate() {
        super.onCreate();
        context = getApplicationContext();
    }

    public static Context getContext(){
        return context;
    }
}

 

الكود:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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=".ui.MainActivity">

    <android.support.v4.widget.SwipeRefreshLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/swipe_to_refresh">

        <android.support.v7.widget.RecyclerView
            android:id="@+id/recyclerview"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginTop="5dp" />

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

</RelativeLayout>

 
 
 

الكود:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="wrap_content">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/name"
        android:layout_margin="10dp"
        android:textColor="#000"
        android:text="Student Name"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/major"
        android:layout_margin="10dp"
        android:layout_alignParentEnd="true"
        android:text="Student Major"/>

</RelativeLayout>

 
 
 

الكود:

import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;

import com.example.asus.databasedebug.R;
import com.example.asus.databasedebug.database.StudentRepository;

public class MainActivity extends AppCompatActivity {

    private RecyclerView mRecyclerView;
    private StudentAdapter adapter;
    private SwipeRefreshLayout swipeRefreshLayout;

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

        // Initialize views
        mRecyclerView = findViewById(R.id.recyclerview);
        swipeRefreshLayout = findViewById(R.id.swipe_to_refresh);

        // Initialize adapter
        adapter = new StudentAdapter(StudentRepository.getInstance().getStudents());


        // Configure recyclerview
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false));
        mRecyclerView.setAdapter(adapter);

        // Swipe listener
        swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                adapter.setList(StudentRepository.getInstance().getStudents());
                adapter.notifyDataSetChanged();

                swipeRefreshLayout.setRefreshing(false);
            }
        });

    }
}

 

الكود:

import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.example.asus.databasedebug.R;
import com.example.asus.databasedebug.pojo.Student;

import java.util.List;

public class StudentAdapter extends RecyclerView.Adapter<StudentAdapter.ViewHolder> {

    private List<Student> studentList;

    public StudentAdapter(List<Student> list){
        studentList = list ;
    }

    public void setList(List<Student> list){
        studentList = list;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
        return new ViewHolder(LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.item_student, null));
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder viewHolder, int index) {
        viewHolder.name.setText(studentList.get(index).getName());
        viewHolder.major.setText(studentList.get(index).getMajor());
    }

    @Override
    public int getItemCount() {
        return ( studentList == null ) ? 0 : studentList.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder{

        TextView name, major;

        public ViewHolder(@NonNull View itemView) {
            super(itemView);

            name = itemView.findViewById(R.id.name);
            major = itemView.findViewById(R.id.major);
        }
    }
}