diff --git a/app/google-services.json b/app/google-services.json
new file mode 100644
index 0000000..cc555ea
--- /dev/null
+++ b/app/google-services.json
@@ -0,0 +1,29 @@
+{
+  "project_info": {
+    "project_number": "317219128586",
+    "project_id": "oplogy-b6971",
+    "storage_bucket": "oplogy-b6971.appspot.com"
+  },
+  "client": [
+    {
+      "client_info": {
+        "mobilesdk_app_id": "1:317219128586:android:c29583456e8fbd5f12a6f3",
+        "android_client_info": {
+          "package_name": "com.example.oplogy"
+        }
+      },
+      "oauth_client": [],
+      "api_key": [
+        {
+          "current_key": "AIzaSyDaULi2TFHLiscR7DSZBCKS08d76Rtb49c"
+        }
+      ],
+      "services": {
+        "appinvite_service": {
+          "other_platform_oauth_client": []
+        }
+      }
+    }
+  ],
+  "configuration_version": "1"
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/example/oplogy/CreateUUID.java b/app/src/main/java/com/example/oplogy/CreateUUID.java
index 5d3aaf9..82924f1 100644
--- a/app/src/main/java/com/example/oplogy/CreateUUID.java
+++ b/app/src/main/java/com/example/oplogy/CreateUUID.java
@@ -1,14 +1,12 @@
 package com.example.oplogy;
 
-import androidx.appcompat.app.AppCompatActivity;
+import java.util.UUID;
 
-import android.os.Bundle;
+public class CreateUUID {
 
-public class CreateUUID extends AppCompatActivity {
-
-    @Override
-    protected void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        setContentView(R.layout.create_uuid);
+    public static String generateUUID() {
+        // UUIDを生成する処理
+        UUID uuid = UUID.randomUUID();
+        return uuid.toString();
     }
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/example/oplogy/MainActivity.java b/app/src/main/java/com/example/oplogy/MainActivity.java
index e5bc0e8..5ec7e3a 100644
--- a/app/src/main/java/com/example/oplogy/MainActivity.java
+++ b/app/src/main/java/com/example/oplogy/MainActivity.java
@@ -1,13 +1,17 @@
 package com.example.oplogy;
 
+import androidx.appcompat.app.AlertDialog;
 import androidx.appcompat.app.AppCompatActivity;
 
+import android.content.DialogInterface;
 import android.content.Intent;
 import android.os.Bundle;
+import android.util.Log;
 import android.view.View;
 import android.widget.Button;
 import android.widget.ImageView;
 import android.widget.TextView;
+import android.widget.Toast;
 
 public class MainActivity extends AppCompatActivity implements View.OnClickListener{
 
@@ -61,8 +65,7 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
 //        ID作成のクリック処理
         if(view == creatUUID){
             imageUuid.setImageResource(R.drawable.ischecked_uuid);
-            Intent toCreateUUID = new Intent(MainActivity.this, CreateUUID.class);
-            startActivity(toCreateUUID);
+            showUUIDYesNoDialog();//UUIDを表示するかのダイアログ
 
         }
 //        セットアップのクリック処理
@@ -83,9 +86,28 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
             Intent toSubmission = new Intent(MainActivity.this,SubmissionActivity.class);
             startActivity(toSubmission);
         }
-
-
     }
+    private void showUUIDYesNoDialog() {
+        //ダイアログの表示
+        AlertDialog.Builder builder = new AlertDialog.Builder(this);
+        builder.setTitle("クラスID");
+        builder.setMessage("あなたのクラスIDを表示しますか？");
 
-
+        //YESのときは初回はUUIDを生成、表示
+        //二回目以降は保存されたUUIDを表示
+        builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
+            @Override
+            public void onClick(DialogInterface dialog, int which) {
+                String classId = CreateUUID.generateUUID();//classIDにuuidが入ってる
+                Toast.makeText(MainActivity.this, "クラスID: " + classId, Toast.LENGTH_SHORT).show();//テスト用
+            }
+        });
+        builder.setNegativeButton("No", new DialogInterface.OnClickListener() {
+            @Override
+            public void onClick(DialogInterface dialog, int which) {
+                Log.d("DialogNO","DialogでNoが選ばれました");
+            }
+        });
+        builder.show();
+    }
 }
\ No newline at end of file