[Kotlin] Room

build.gradle (Module: app)

apply plugin: 'kotlin-kapt'

dependencies {
    // RecyclerView
    implementation 'androidx.recyclerview:recyclerview:1.1.0'

    // Room
    implementation 'androidx.room:room-runtime:2.2.5'
    kapt 'androidx.room:room-compiler:2.2.5'
    testImplementation 'androidx.room:room-testing:2.2.5'
}

 

 

 

 

 

 

 

User.kt

package com.jwsoft.kotlinproject

import androidx.room.ColumnInfo
import androidx.room.Entity
import androidx.room.PrimaryKey

@Entity(tableName = "user")
data class User (

    @PrimaryKey(autoGenerate = true) var id: Long?,
    @ColumnInfo(name = "name") var name: String,
    @ColumnInfo(name = "phone") var phone: String,
    @ColumnInfo(name = "age") var age: Int

) {
    constructor() : this(null, "", "", 0)
}

 

 

 

 

 

 

 

 

UserDao.kt

package com.jwsoft.kotlinproject

import androidx.room.Dao
import androidx.room.Insert
import androidx.room.OnConflictStrategy
import androidx.room.Query

@Dao
interface UserDao {

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    fun insert(user: User)

    @Query("SELECT * FROM user ORDER BY age ASC")
    fun getAll(): List<User>

}

 

 

 

 

 

 

 

 

UserDB.kt

package com.jwsoft.kotlinproject

import android.content.Context
import androidx.room.Database
import androidx.room.Room
import androidx.room.RoomDatabase

@Database(entities = [User::class], version = 1)
abstract class UserDB : RoomDatabase() {

    abstract fun userDao(): UserDao

    companion object {
        var INSTANCE: UserDB? = null

        fun getInstance(context: Context): UserDB {
            if (INSTANCE == null) {
                INSTANCE = Room.databaseBuilder(context, UserDB::class.java, "MyApp.db")
                    .fallbackToDestructiveMigration()
                    .build()
            }
            return INSTANCE!!
        }
    }

}

 

 

 

 

 

 

 

 

recyclerview_item.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"
    android:layout_width="match_parent"
    android:layout_height="80dp"
    android:layout_margin="8dp">

    <ImageView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#FFBBBB"/>

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:gravity="center"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintRight_toLeftOf="@+id/tvAge">

        <TextView
            android:id="@+id/tvName"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="32dp"
            android:textStyle="bold"
            android:hint="James Kim" />

        <TextView
            android:id="@+id/tvPhone"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:hint="010-1234-5678"
            android:textSize="18dp"
            android:textStyle="italic|bold"
            android:inputType="phone"/>

    </LinearLayout>

    <TextView
        android:id="@+id/tvAge"
        android:layout_width="60dp"
        android:layout_height="60dp"
        android:layout_marginRight="10dp"
        android:hint="30"
        android:textSize="40dp"
        android:gravity="center"
        android:textStyle="bold"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"/>

</androidx.constraintlayout.widget.ConstraintLayout>

recyclerview_item.xml

 

 

 

 

 

 

 

RecyclerViewAdapter.kt

package com.jwsoft.kotlinproject

import android.content.Context
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.recyclerview.widget.RecyclerView

class RecyclerViewAdapter(var users: List<User>) : RecyclerView.Adapter<RecyclerViewAdapter.MyViewHolder>() {

    inner class MyViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        var tvName: TextView = itemView.findViewById(R.id.tvName)
        var tvPhone: TextView = itemView.findViewById(R.id.tvPhone)
        var tvAge: TextView = itemView.findViewById(R.id.tvAge)

        fun bind(user: User) {
            tvName.text = user.name
            tvPhone.text = user.phone
            tvAge.text = user.age.toString()
        }
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
        val context = parent.context
        val inflater = context.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater
        val view = inflater.inflate(R.layout.recyclerview_item, parent, false)

        return MyViewHolder(view)
    }

    override fun getItemCount(): Int = users.size

    override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
        holder.bind(users[position])
    }
}

 

 

 

 

 

 

 

 

activity_add.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".AddActivity">


    <TextView
        android:id="@+id/tvName"
        android:text="Name"
        android:textSize="18dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="32dp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintVertical_bias="0.41000003"/>

    <EditText
        android:id="@+id/etName"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:inputType="textPersonName"
        android:ems="10"
        app:layout_constraintBottom_toBottomOf="@+id/tvName"
        app:layout_constraintTop_toTopOf="@+id/tvName"
        app:layout_constraintStart_toEndOf="@+id/tvName"
        android:layout_marginStart="32dp"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginEnd="32dp"/>

    <TextView
        android:id="@+id/tvPhone"
        android:text="Number"
        android:textSize="18dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="40dp"
        app:layout_constraintTop_toBottomOf="@+id/tvName"
        app:layout_constraintStart_toStartOf="@+id/tvName"/>

    <EditText
        android:id="@+id/etPhone"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:ems="10"
        app:layout_constraintStart_toStartOf="@+id/etName"
        app:layout_constraintTop_toTopOf="@+id/tvPhone"
        app:layout_constraintBottom_toBottomOf="@+id/tvPhone"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginEnd="32dp"
        android:inputType="phone"/>

    <TextView
        android:id="@+id/tvAge"
        android:text="Age"
        android:textSize="18dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="40dp"
        app:layout_constraintTop_toBottomOf="@+id/tvPhone"
        app:layout_constraintStart_toStartOf="@+id/tvPhone"/>

    <EditText
        android:id="@+id/etAge"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:ems="10"
        app:layout_constraintStart_toStartOf="@+id/etPhone"
        app:layout_constraintTop_toTopOf="@+id/tvAge"
        app:layout_constraintBottom_toBottomOf="@+id/tvAge"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginEnd="32dp"
        android:inputType="phone"/>

    <Button
        android:id="@+id/btnAdd"
        android:text="OK"
        android:layout_width="0dp"
        android:layout_height="49dp"
        android:layout_marginBottom="8dp"
        android:textSize="24dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginStart="8dp"
        android:layout_marginEnd="8dp"/>

</androidx.constraintlayout.widget.ConstraintLayout>

activity_add.xml

 

 

 

 

 

 

AddActivity.kt

package com.jwsoft.kotlinproject

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import kotlinx.android.synthetic.main.activity_add.*

class AddActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_add)

        btnAdd.setOnClickListener {
            Thread {
                var name = etName.text.toString()
                var phone = etPhone.text.toString()
                var age = Integer.parseInt(etAge.text.toString())

                var user = User(null, name, phone, age)
                UserDB.getInstance(applicationContext).userDao().insert(user)

                val intent = Intent(this, MainActivity::class.java)
                startActivity(intent)
                finish()
            }.start()
        }

    }
}

 

 

 

 

 

 

 

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">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        tools:listitem="@layout/recyclerview_item"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintBottom_toTopOf="@+id/btnAdd"/>

    <Button
        android:id="@+id/btnAdd"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="add"
        android:textSize="24dp"
        app:layout_constraintTop_toBottomOf="@+id/recyclerView"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"/>

</androidx.constraintlayout.widget.ConstraintLayout>

activity_main.xml

 

 

 

 

 

 

MainActivity.kt

package com.jwsoft.kotlinproject

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        Thread {
            val users: List<User> = UserDB.getInstance(applicationContext).userDao().getAll()
            val adapter = RecyclerViewAdapter(users)
            recyclerView.adapter = adapter
            recyclerView.setHasFixedSize(true)
            recyclerView.layoutManager = LinearLayoutManager(
                this,
                RecyclerView.VERTICAL,
                false
            )
        }.start()


        btnAdd.setOnClickListener {
            val intent = Intent(this, AddActivity::class.java)
            startActivity(intent)
            finish()
        }

    }
}

실행 결과

 

ADD 버튼 클릭 후

 

 

정보 입력

 

OK 버튼 클릭 후

 

나이 오름차순 정렬