MainActivity.kt
package com.example.roomexamples
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.text.method.ScrollingMovementMethod
import com.android.volley.Request
import com.android.volley.Response
import com.android.volley.toolbox.JsonArrayRequest
import com.android.volley.toolbox.Volley
import kotlinx.android.synthetic.main.activity_main.*
import org.jetbrains.anko.doAsync
import org.jetbrains.anko.toast
import org.jetbrains.anko.uiThread
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val room = RoomSingleton.getInstance(this)
textView.movementMethod = ScrollingMovementMethod()
// Insert some products in database
btnInsert.setOnClickListener {
it.isEnabled = false
val url = "https://pastebin.com/raw/BrQjM5dX"
val request = JsonArrayRequest(
Request.Method.GET,
url,
null,
Response.Listener{
val list = arrayListOf<Employee>()
for (i in 0 until it.length()){
val obj = it.getJSONObject(i)
val name = obj.getString("name")
val salary = obj.getLong("salary")
val age = obj.getInt("age")
val emp = Employee(null,name,salary,age)
list.add(emp)
}
doAsync {
room.empDao().insertAll(list)
uiThread {
toast("done")
}
}
},Response.ErrorListener {
toast(it.toString())
}
)
// Add the request to the RequestQueue.
Volley.newRequestQueue(this).add(request)
}
btn1.setOnClickListener {
doAsync {
val list = room.empDao().empLIKEtha()
uiThread {
textView.text = ""
list.forEach{
textView.append("" + it.id + ". ")
textView.append(it.name)
textView.append(" Age: " + it.age)
textView.append(" Salary: " + it.salary + "\n")
}
}
}
}
btn2.setOnClickListener {
doAsync {
// You need to enclose the % characters in input query
val list = room.empDao().empByLike("%al%")
// Or
//val list = room.empDao().empByLike("%al")
// Or
//val list = room.empDao().empByLike("al%")
uiThread {
textView.text = ""
list.forEach{
textView.append("" + it.id + ". ")
textView.append(it.name)
textView.append(" Age: " + it.age)
textView.append(" Salary: " + it.salary + "\n")
}
}
}
}
}
}
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">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="32dp"
android:layout_marginEnd="8dp"
android:text=""
android:textAppearance="@style/TextAppearance.AppCompat.Large"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/btnInsert"
/>
<Button
android:id="@+id/btnInsert"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="Insert"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
/>
<Button
android:id="@+id/btn1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="LIKE %tha%"
app:layout_constraintStart_toEndOf="@+id/btnInsert"
app:layout_constraintTop_toTopOf="parent"
android:textAllCaps="false"
/>
<Button
android:id="@+id/btn2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="Like %al%"
app:layout_constraintStart_toEndOf="@+id/btn1"
app:layout_constraintTop_toTopOf="parent"
android:textAllCaps="false"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
RoomSingleton.kt
package com.example.roomexamples
import android.content.Context
import androidx.room.*
@Database(entities = arrayOf(Employee::class), version = 1, exportSchema = false)
abstract class RoomSingleton : RoomDatabase(){
abstract fun empDao(): EmpDao
companion object{
private var INSTANCE: RoomSingleton? = null
fun getInstance(context: Context): RoomSingleton{
if (INSTANCE == null){
INSTANCE = Room.databaseBuilder(
context,
RoomSingleton::class.java,
"roomdb")
.build()
}
return INSTANCE as RoomSingleton
}
}
}
RoomDao.kt
package com.example.roomexamples
import androidx.room.*
@Entity(tableName = "empTbl")
data class Employee(
@PrimaryKey(autoGenerate = true)
var id:Int?=null,
var name:String,
var salary:Long,
var age:Int
)
@Dao
interface EmpDao{
@Query("SELECT * FROM empTbl")
fun allEmployee():List<Employee>
@Query("SELECT * FROM empTbl WHERE name LIKE '%tha%'")
fun empLIKEtha():List<Employee>
@Query("SELECT * FROM empTbl WHERE name LIKE:searchText")
fun empByLike(searchText:String):List<Employee>
@Insert(onConflict = OnConflictStrategy.REPLACE)
fun insert(emp:Employee)
@Insert(onConflict = OnConflictStrategy.REPLACE)
fun insertAll(list:List<Employee>)
}
app build.gradle [required]
apply plugin: 'kotlin-kapt'
dependencies {
// Room
def room_version = "2.2.0-alpha01"
implementation "androidx.room:room-runtime:$room_version"
kapt 'androidx.room:room-compiler:2.2.0-alpha01'
// Anko Commons
implementation "org.jetbrains.anko:anko-commons:0.10.8"
// Volley network library
implementation 'com.android.volley:volley:1.1.1'
}
