diff --git a/app/src/main/java/keijumt/devandroid/common/Calculate.kt b/app/src/main/java/keijumt/devandroid/common/Calculate.kt
new file mode 100644
index 0000000..58ec5f4
--- /dev/null
+++ b/app/src/main/java/keijumt/devandroid/common/Calculate.kt
@@ -0,0 +1,34 @@
+package keijumt.devandroid.common
+
+import android.os.AsyncTask
+
+class Calculate(val callback: Callback<Int>) : AsyncTask<Int, Int, Int>() {
+
+    // ui thread
+    override fun onPreExecute() {
+        println("onPreExecute")
+    }
+
+    override fun doInBackground(vararg params: Int?): Int {
+        try {
+            println("doInBackground")
+            Thread.sleep(3000)
+        } catch (e: Exception) {
+
+        }
+        val value = params.get(0) ?: 1
+        return value * value
+    }
+
+    override fun onProgressUpdate(vararg values: Int?) {
+        println("onPorgressUpdate")
+    }
+
+    override fun onPostExecute(result: Int?) {
+        callback.execute(result)
+    }
+
+    interface Callback<T> {
+        fun execute(value: T?)
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/keijumt/devandroid/viewmodel/AsyncViewModel.kt b/app/src/main/java/keijumt/devandroid/viewmodel/AsyncViewModel.kt
index f55213c..84419cf 100644
--- a/app/src/main/java/keijumt/devandroid/viewmodel/AsyncViewModel.kt
+++ b/app/src/main/java/keijumt/devandroid/viewmodel/AsyncViewModel.kt
@@ -1,7 +1,52 @@
 package keijumt.devandroid.viewmodel
 
+import io.reactivex.Flowable
+import keijumt.devandroid.common.Calculate
+import kotlinx.coroutines.experimental.android.UI
+import kotlinx.coroutines.experimental.async
+import kotlinx.coroutines.experimental.delay
+import kotlinx.coroutines.experimental.launch
+import org.reactivestreams.Subscriber
 import javax.inject.Inject
 
 class AsyncViewModel @Inject constructor() : BaseViewModel() {
-    
+
+    init {
+        println("start initialize")
+        val callback = object : Calculate.Callback<Int> {
+            override fun execute(value: Int?) {
+                println("callback execute value is ${value}")
+                println("call back thread is ${Thread.currentThread().name}")
+            }
+        }
+        val asyncCalc = Calculate(callback)
+        asyncCalc.execute(10)
+        println("finish initialize")
+
+        launch(UI) {
+            val calc1 = async {
+                println("start async calc1")
+                delay(3000)
+                return@async 10
+            }
+            val calc2 = async {
+                println("start async calc2")
+                delay(3000)
+                return@async 6
+            }
+            val value1 = calc1.await()
+            val value2 = calc2.await()
+            println("value1 is ${value1}, value2 is ${value2}")
+            println("async await thread is ${Thread.currentThread().name}")
+        }
+
+        val flowable = object : Flowable<Int>() {
+            override fun subscribeActual(s: Subscriber<in Int>?) {
+                println("start flowable")
+                Thread.sleep(3000)
+                s?.onNext(10)
+            }
+        }
+
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_async.xml b/app/src/main/res/layout/activity_async.xml
index d8fb324..49d2d14 100644
--- a/app/src/main/res/layout/activity_async.xml
+++ b/app/src/main/res/layout/activity_async.xml
@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout
-    xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
+<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
     android:layout_height="match_parent">
 
+    <fragment
+        android:id="@+id/fragment_async"
+        android:name="keijumt.devandroid.fragment.AsyncFragment"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent" />
+
 </android.support.constraint.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_async.xml b/app/src/main/res/layout/fragment_async.xml
index 7a39090..a976362 100644
--- a/app/src/main/res/layout/fragment_async.xml
+++ b/app/src/main/res/layout/fragment_async.xml
@@ -11,6 +11,6 @@
     <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
         android:layout_width="match_parent"
         android:layout_height="match_parent">
-
+        
     </android.support.constraint.ConstraintLayout>
 </layout>
\ No newline at end of file