diff --git a/app/src/main/java/com/example/sprout/refactor/activity/RoomMainActivity.java b/app/src/main/java/com/example/sprout/refactor/activity/RoomMainActivity.java
index 2eecb99..0817bda 100644
--- a/app/src/main/java/com/example/sprout/refactor/activity/RoomMainActivity.java
+++ b/app/src/main/java/com/example/sprout/refactor/activity/RoomMainActivity.java
@@ -2,19 +2,16 @@
 
 import android.databinding.DataBindingUtil;
 import android.os.Bundle;
-import android.widget.Toast;
 
 import com.example.sprout.R;
 import com.example.sprout.databinding.RfActivityRoomMainBinding;
 import com.example.sprout.refactor.Constant;
 import com.example.sprout.refactor.adapter.RoomMainAdapter;
-import com.example.sprout.refactor.common.ActivityEvent;
-import com.example.sprout.refactor.contract.ViewContract;
 import com.example.sprout.refactor.viewmodel.RoomMainViewModel;
 
 import framework.gameMain.RealTimeActivity;
 
-public class RoomMainActivity extends RealTimeActivity implements ViewContract {
+public class RoomMainActivity extends RealTimeActivity {
 
     private RoomMainViewModel roomMainViewModel = null;
 
@@ -22,7 +19,7 @@
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         RfActivityRoomMainBinding binding = DataBindingUtil.setContentView(this, R.layout.rf_activity_room_main);
-        roomMainViewModel = new RoomMainViewModel(new RoomMainAdapter(this), (ViewContract) this);
+        roomMainViewModel = new RoomMainViewModel(new RoomMainAdapter(this));
         binding.setViewModel(roomMainViewModel);
         getLifecycle().addObserver(roomMainViewModel);
     }
@@ -31,6 +28,7 @@
     protected void onResume() {
         super.onResume();
         this.start(Constant.ROOM_UPDATE_DELAY, Constant.ROOM_UPDATE_INTERVAL);
+        addUiObserver(roomMainViewModel);
     }
 
     @Override
@@ -43,24 +41,4 @@
     protected void update(long interval) {
         roomMainViewModel.update();
     }
-
-    @Override
-    public void startActivity(ActivityEvent event) {
-
-    }
-
-    @Override
-    public void finishActivity() {
-        finish();
-    }
-
-    @Override
-    public void showShortToast(String message) {
-        Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
-    }
-
-    @Override
-    public void showLongToast(String message) {
-        Toast.makeText(this, message, Toast.LENGTH_LONG).show();
-    }
 }