diff --git a/app/src/main/java/com/example/sprout/refactor/activity/RegistrationActivity.java b/app/src/main/java/com/example/sprout/refactor/activity/RegistrationActivity.java
index 5a3fbc4..d33be6c 100644
--- a/app/src/main/java/com/example/sprout/refactor/activity/RegistrationActivity.java
+++ b/app/src/main/java/com/example/sprout/refactor/activity/RegistrationActivity.java
@@ -1,15 +1,10 @@
 package com.example.sprout.refactor.activity;
 
-import android.content.Intent;
 import android.databinding.DataBindingUtil;
 import android.os.Bundle;
-import android.support.v7.app.AppCompatActivity;
-import android.widget.Toast;
 
 import com.example.sprout.R;
 import com.example.sprout.databinding.RfActivityRegistrationBinding;
-import com.example.sprout.refactor.common.ActivityEvent;
-import com.example.sprout.refactor.contract.ViewContract;
 import com.example.sprout.refactor.viewmodel.RegistrationViewModel;
 
 /**
@@ -17,7 +12,7 @@
  *
  * @author matsumoto_k
  */
-public class RegistrationActivity extends AppCompatActivity implements ViewContract {
+public class RegistrationActivity extends BaseActivity {
 
     private RfActivityRegistrationBinding binding = null;
     private RegistrationViewModel registrationViewModel = null;
@@ -26,32 +21,20 @@
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         binding = DataBindingUtil.setContentView(this, R.layout.rf_activity_registration);
-        registrationViewModel = new RegistrationViewModel((ViewContract) this);
+        registrationViewModel = new RegistrationViewModel();
         binding.setViewModel(registrationViewModel);
         getLifecycle().addObserver(registrationViewModel);
     }
 
     @Override
-    public void showShortToast(String message) {
-        Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
+    protected void onResume() {
+        super.onResume();
+        addUiObserver(registrationViewModel);
     }
 
     @Override
-    public void showLongToast(String message) {
-        Toast.makeText(this, message, Toast.LENGTH_LONG).show();
-    }
-
-    @Override
-    public void startActivity(ActivityEvent event) {
-        switch (event) {
-            case ROOM_LIST:
-                startActivity(new Intent(RegistrationActivity.this, RoomListActivity.class));
-                break;
-        }
-    }
-
-    @Override
-    public void finishActivity() {
-        finish();
+    protected void onPause() {
+        super.onPause();
+        removeUiObserver(registrationViewModel);
     }
 }