diff --git a/app/src/main/java/com/example/tampopo_client/Tampopo.java b/app/src/main/java/com/example/tampopo_client/Tampopo.java
index 6ca0763..52a0285 100644
--- a/app/src/main/java/com/example/tampopo_client/Tampopo.java
+++ b/app/src/main/java/com/example/tampopo_client/Tampopo.java
@@ -1,11 +1,14 @@
 package com.example.tampopo_client;
 
 import android.app.Application;
+import android.content.SharedPreferences;
 
 public class Tampopo extends Application {
-  public String getUserId;
+  private SharedPreferences prefs;
 
-  public String getToken;
+  //public String getUserId;
+
+  //public String getToken;
   private String token;
   private String userId;
   private String password;
@@ -13,11 +16,28 @@
   private String mailaddress;
   private String nickname;
   private String icon;
+//
+//  @Override
+//  public void onCreate() {
+//    super.onCreate();
+//    prefs = getSharedPreferences("user_prefs", MODE_PRIVATE);
+//
+//    // 起動時に保存された値を読み込む
+//    token = prefs.getString("token", "");
+//    userId = prefs.getString("userId", "");
+//    password = prefs.getString("password", "");
+//    chatroomId = prefs.getString("chatroomId", "");
+//    mailaddress = prefs.getString("mailaddress", "");
+//    nickname = prefs.getString("nickname", "");
+//    icon = prefs.getString("icon", "");
+//  }
+
 
   public String getToken() {return token;}
 
   public void setToken(String token) {
     this.token = token;
+    //prefs.edit().putString("token", token).apply();
   }
 
   public String getUserId() {
@@ -26,14 +46,25 @@
 
   public void setUserId(String userId) {
     this.userId = userId;
+    //prefs.edit().putString("userId", userId).apply();
   }
 
+  public String getMailaddress() { return mailaddress; }
+
+  public void setMailaddress(String mailaddress) {
+    this.mailaddress = mailaddress;
+    //prefs.edit().putString("mailaddress", mailaddress).apply();
+  }
+
+
+
   public String getPassword() {
     return password;
   }
 
   public void setPassword(String password) {
     this.password = password;
+    //prefs.edit().putString("password", password).apply();
   }
 
   public String getChatroomId() {
@@ -44,15 +75,19 @@
     this.chatroomId = ChatroomId;
   }
 
-  public String getMailaddress() { return mailaddress; }
 
-  public void setMailaddress(String mailaddress) {this.mailaddress = mailaddress; }
 
   public String getNickname() { return nickname; }
 
-  public void setNickname(String nickname) {this.nickname = nickname; }
+  public void setNickname(String nickname) {
+    this.nickname = nickname;
+    //prefs.edit().putString("nickname", nickname).apply();
+  }
 
   public String getIcon() { return icon; }
 
-  public void setIcon(String icon) {this.icon = icon; }
+  public void setIcon(String icon) {
+    this.icon = icon;
+    //prefs.edit().putString("icon", icon).apply();
+  }
 }
diff --git a/app/src/main/java/com/example/tampopo_client/models/User.java b/app/src/main/java/com/example/tampopo_client/models/User.java
index 706145d..6533361 100644
--- a/app/src/main/java/com/example/tampopo_client/models/User.java
+++ b/app/src/main/java/com/example/tampopo_client/models/User.java
@@ -55,4 +55,7 @@
     public void    setToken(String token){
         this.token = token;
     }
+
+    public void setPassword(String body) {
+    }
 }
diff --git a/app/src/main/java/com/example/tampopo_client/viewmodels/UserViewModel.java b/app/src/main/java/com/example/tampopo_client/viewmodels/UserViewModel.java
index 4fe101d..4fc6812 100644
--- a/app/src/main/java/com/example/tampopo_client/viewmodels/UserViewModel.java
+++ b/app/src/main/java/com/example/tampopo_client/viewmodels/UserViewModel.java
@@ -40,11 +40,11 @@
 public class UserViewModel extends ViewModel {
 
     private final Retrofit retrofit;
-    private final UserResource userResource;
-    private final MutableLiveData<User> user   = new MutableLiveData<>();
+    private static UserResource userResource;
+    private static final MutableLiveData<User> user   = new MutableLiveData<>();
     private final MutableLiveData<String> token  = new MutableLiveData<>();
-    private final MutableLiveData<Boolean>loading = new MutableLiveData<>(false);
-    private final MutableLiveData<String> error  = new MutableLiveData<>();
+    private static final MutableLiveData<Boolean>loading = new MutableLiveData<>(false);
+    private static final MutableLiveData<String> error  = new MutableLiveData<>();
 
     //コンストラクタ
     public UserViewModel(){
@@ -59,7 +59,7 @@
     public LiveData<User> getUser()   { return user;   }
     public LiveData<String> getToken()  { return token;  }
     public LiveData<Boolean>isLoading() { return loading;}
-    public LiveData<String> getError()  { return error;  }
+    public static LiveData<String> getError()  { return error;  }
 
     //新規登録　enqueueで非同期処理、Callbackで成功失敗の処理、LiveDataに反映
     //サーバーから返ってきた型と合わせないとFailureに流れる
@@ -104,5 +104,90 @@
         });
     }
 
+    //ニックネームの変更（市井）
+    public void updateName(String userId, String newName, String tokenValue) {
+        loading.setValue(true);
+
+        userResource.updateName(userId, newName, tokenValue).enqueue(new Callback<String>() {
+            @Override
+            public void onResponse(Call<String> call, Response<String> response) {
+                loading.setValue(false);
+                if (response.isSuccessful()) {
+                    // LiveData に更新
+                    User currentUser = user.getValue();
+                    if (currentUser != null) {
+                        currentUser.setName(response.body());
+                        user.setValue(currentUser);
+                    }
+                } else {
+                    error.setValue("ニックネーム変更失敗: " + response.code());
+                }
+            }
+
+            @Override
+            public void onFailure(Call<String> call, Throwable t) {
+                loading.setValue(false);
+                error.setValue("通信エラー: " + t.getMessage());
+            }
+        });
+    }
+    //パスワードの変更（市井）
+    public void updatePassword(String userId, String newPassword) {
+        loading.setValue(true);
+
+        userResource.updatePassword(userId, newPassword).enqueue(new Callback<Void>() {
+            @Override
+            public void onResponse(Call<Void> call, Response<Void> response) {
+                loading.setValue(false);
+                if (response.isSuccessful()) {
+                    // LiveData に更新
+                    User currentUser = user.getValue();
+                    if (currentUser != null) {
+                        currentUser.setPassword(newPassword);
+                        user.setValue(currentUser);
+                    }
+                } else {
+                    error.setValue("パスワード変更失敗: " + response.code());
+                }
+            }
+
+            @Override
+            public void onFailure(Call<Void> call, Throwable t) {
+                loading.setValue(false);
+                error.setValue("通信エラー: " + t.getMessage());
+            }
+        });
+    }
+
+
+    //emailの変更（市井）
+    public void updateEmail(String userId, String newEmale, String tokenValue) {
+        loading.setValue(true);
+
+        userResource.updateEmail(userId, newEmale, tokenValue).enqueue(new Callback<String>() {
+            @Override
+            public void onResponse(Call<String> call, Response<String> response) {
+                loading.setValue(false);
+                if (response.isSuccessful()) {
+                    // LiveData に更新
+                    User currentUser = user.getValue();
+                    if (currentUser != null) {
+                        currentUser.setEmail(response.body());
+                        user.setValue(currentUser);
+                    }
+                } else {
+                    error.setValue("メールアドレス変更失敗: " + response.code());
+                }
+            }
+
+            @Override
+            public void onFailure(Call<String> call, Throwable t) {
+                loading.setValue(false);
+                error.setValue("通信エラー: " + t.getMessage());
+            }
+        });
+    }
+
+
     //viewModelのところでを呼び出すがフレンド系は西村さんの方で管理する
 }
diff --git a/app/src/main/java/com/example/tampopo_client/views/AccountActivity.java b/app/src/main/java/com/example/tampopo_client/views/AccountActivity.java
index 90ed189..fbc4948 100644
--- a/app/src/main/java/com/example/tampopo_client/views/AccountActivity.java
+++ b/app/src/main/java/com/example/tampopo_client/views/AccountActivity.java
@@ -6,18 +6,24 @@
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.ImageButton;
+import android.widget.Toast;
 
 import androidx.activity.EdgeToEdge;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.core.graphics.Insets;
 import androidx.core.view.ViewCompat;
 import androidx.core.view.WindowInsetsCompat;
+import androidx.lifecycle.ViewModelProvider;
+import androidx.lifecycle.Observer;
 
 import com.example.tampopo_client.R;
 import com.example.tampopo_client.Tampopo;
+import com.example.tampopo_client.viewmodels.UserViewModel;
 
 public class AccountActivity extends AppCompatActivity {
 
+    private UserViewModel userViewModel;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -29,78 +35,107 @@
             return insets;
         });
 
+        // ViewModel初期化
+        userViewModel = new ViewModelProvider(this).get(UserViewModel.class);
 
         //アカウント編集画面から設定画面への遷移
-        ImageButton buttonReturn = (ImageButton)findViewById(R.id.buttonReturn);
-        buttonReturn.setOnClickListener(new View.OnClickListener() {
-            public void onClick(View v) {
-                Intent intent = new Intent(AccountActivity.this, SettingActivity.class);
-                startActivity(intent);
-            }
+        ImageButton buttonReturn = findViewById(R.id.buttonReturn);
+        buttonReturn.setOnClickListener(v -> {
+            Intent intent = new Intent(AccountActivity.this, SettingActivity.class);
+            startActivity(intent);
         });
 
         //もともとのメールアドレスを表示
-        EditText mailbuttonInput = (EditText) findViewById(R.id.mailbutton);
+        EditText mailbuttonInput = findViewById(R.id.mailbutton);
         mailbuttonInput.setText(((Tampopo) AccountActivity.this.getApplication()).getMailaddress());
 
         //決定ボタンを押したときにパスワードとメールアドレスを保存
-        Button dicisionbutton = (Button) findViewById(R.id.dicisionbutton);
+        Button dicisionbutton = findViewById(R.id.dicisionbutton);
         dicisionbutton.setOnClickListener(new View.OnClickListener() {
 
-            private Object getApplication;
-
+            @Override
             public void onClick(View v) {
-                //現在のパスワード
-                EditText beforepasswordbuttonInput = (EditText) findViewById(R.id.beforepasswordbutton);
-                String beforepasswordbutton = beforepasswordbuttonInput.getText().toString();
+                Tampopo app = (Tampopo) AccountActivity.this.getApplication();
 
-                //パスワード変更
-                EditText afterpasswordbutton1Input = (EditText) findViewById(R.id.afterpasswordbutton1);
+                //現在の（保存されている）パスワード
+                String currentStoredPassword = app.getPassword() == null ? "" : app.getPassword();
+
+
+                System.out.println("【DEBUG】保存されているパスワード：" + currentStoredPassword);
+                String beforepasswordbutton = null;
+                System.out.println("【DEBUG】入力された現在のパスワード：" + beforepasswordbutton);
+
+
+                //入力された「現在のパスワード」
+                EditText beforepasswordbuttonInput = findViewById(R.id.beforepasswordbutton);
+                beforepasswordbutton = beforepasswordbuttonInput.getText().toString();
+
+                //入力された「新しいパスワード」2回分
+                EditText afterpasswordbutton1Input = findViewById(R.id.afterpasswordbutton1);
                 String afterpasswordbutton1 = afterpasswordbutton1Input.getText().toString();
 
-                EditText afterpasswordbutton2Input = (EditText) findViewById(R.id.afterpasswordbutton2);
-                String afterpasswordbutton2 = afterpasswordbutton1Input.getText().toString();
-                ((Tampopo) AccountActivity.this.getApplication()).setPassword(afterpasswordbutton2);
+                EditText afterpasswordbutton2Input = findViewById(R.id.afterpasswordbutton2);
+                String afterpasswordbutton2 = afterpasswordbutton2Input.getText().toString();
 
-                //メールアドレス登録
-                EditText mailbuttonInput = (EditText) findViewById(R.id.mailbutton);
+                //メールアドレス登録用
+                EditText mailbuttonInput = findViewById(R.id.mailbutton);
                 String mailbutton = mailbuttonInput.getText().toString();
-                ((Tampopo) AccountActivity.this.getApplication()).setMailaddress(mailbutton);
 
-                //もし前のパスワードが合っていなかったはじくようにする
+                // バリデーション
+                // 1) 現在のパスワードが一致するか
+                if (!beforepasswordbutton.equals(currentStoredPassword)) {
+                    Toast.makeText(AccountActivity.this, "現在のパスワードが違います。", Toast.LENGTH_SHORT).show();
+                    return;
+                }
 
+                // 2) 新しいパスワードが2回一致しているか
+                if (!afterpasswordbutton1.equals(afterpasswordbutton2)) {
+                    Toast.makeText(AccountActivity.this, "新しいパスワードが一致しません。", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                // 3) 新しいパスワードが現在のものと同じでないか（同じならはじく）
+                if (afterpasswordbutton1.equals(currentStoredPassword)) {
+                    Toast.makeText(AccountActivity.this, "新しいパスワードは現在のパスワードと同じです。別のパスワードを入力してください。", Toast.LENGTH_SHORT).show();
+                    return;
+                }
+
+                // 全て通れば保存
+                app.setPassword(afterpasswordbutton1);
+                app.setMailaddress(mailbutton);
+
+                Toast.makeText(AccountActivity.this, "アカウント情報を更新しました。", Toast.LENGTH_SHORT).show();
+
+                // Application（Tampopo）に保存（→SharedPreferencesにも自動保存される）
+                app = (Tampopo) getApplication();
+                app.setPassword(afterpasswordbutton1);
+                app.setMailaddress(mailbutton);
+
+//                // ---- ★ サーバに送信する部分 ★ ----
+//                String userId = app.getUserId();
+//                String token = app.getToken();
+//
+//                UserViewModel.updatePassword(userId, afterpasswordbutton1, token);
+//
+//                // サーバ送信の結果を監視して成功したら保存
+//                UserViewModel.getError().observe(this, msg -> {
+//                    if (msg != null) {
+//                        Toast.makeText(AccountActivity.this, msg, Toast.LENGTH_SHORT).show();
+//                    } else {
+//                        // 成功時のみアプリ内も更新
+//                        app.setPassword(afterpasswordbutton1);
+//                        app.setMailaddress(mailbutton);
+//                        Toast.makeText(AccountActivity.this, "アカウント情報を更新しました。", Toast.LENGTH_SHORT).show();
+//
+//                        Intent intent = new Intent(AccountActivity.this, SettingActivity.class);
+//                        startActivity(intent);
+//                    }
 
                 //決定を押したら設定画面に遷移
                 Intent intent = new Intent(AccountActivity.this, SettingActivity.class);
                 startActivity(intent);
+
             }
         });
-
-//        //もし前のパスワードが合っていなかったはじくようにする
-//
-//
-//        //決定を押したら設定画面に遷移
-//        dicisionbutton.setOnClickListener(new View.OnClickListener() {
-//
-//            private Object getApplication;
-//
-//            public void onClick(View v) {
-//
-//                Intent intent = new Intent(AccountActivity.this, SettingActivity.class);
-//                startActivity(intent);
-//
-//
-//            }
-//        });
-
     }
-    @Override
-    protected void onStart() {
-        super.onStart();
-
-        //もともとのメールアドレスを表示
-        EditText mailbuttonInput = (EditText) findViewById(R.id.mailbutton);
-        mailbuttonInput.setText(((Tampopo) AccountActivity.this.getApplication()).getMailaddress());
-
-    }
-}
\ No newline at end of file
+}
diff --git a/app/src/main/java/com/example/tampopo_client/views/FriendListFragment.java b/app/src/main/java/com/example/tampopo_client/views/FriendListFragment.java
index 003375b..722c7b7 100644
--- a/app/src/main/java/com/example/tampopo_client/views/FriendListFragment.java
+++ b/app/src/main/java/com/example/tampopo_client/views/FriendListFragment.java
@@ -87,8 +87,8 @@
         super.onViewCreated(view, savedInstanceState);
         FriendViewModel friendViewModel = new ViewModelProvider(this).get(FriendViewModel.class);
 
-        String userId = ((Tampopo) ((FriendActivity) view.getContext()).getApplication()).getUserId;
-        String token = ((Tampopo) ((FriendActivity) view.getContext()).getApplication()).getToken;
+        String userId = ((Tampopo) ((FriendActivity) view.getContext()).getApplication()).getUserId();
+        String token = ((Tampopo) ((FriendActivity) view.getContext()).getApplication()).getToken();
         friendViewModel.loadFriends(userId, token);
 
         friendViewModel.getFriendIdsLiveData().observe(getViewLifecycleOwner(), new Observer<List<String>>() {
diff --git a/app/src/main/java/com/example/tampopo_client/views/LoginActivity.java b/app/src/main/java/com/example/tampopo_client/views/LoginActivity.java
index 52837ad..5c7ced7 100644
--- a/app/src/main/java/com/example/tampopo_client/views/LoginActivity.java
+++ b/app/src/main/java/com/example/tampopo_client/views/LoginActivity.java
@@ -46,7 +46,14 @@
       @Override
       public void onChanged(String token) {
         if (token != null){
-          ((Tampopo) LoginActivity.this.getApplication()).setToken(token);
+          Tampopo app = (Tampopo) LoginActivity.this.getApplication();
+          app.setToken(token);
+
+          EditText passwordInput = findViewById(R.id.PasswordText);
+          String enteredPassword = passwordInput.getText().toString();
+          app.setPassword(enteredPassword);
+
+
           Intent intent = new Intent(LoginActivity.this, MainActivity.class);
           startActivity(intent);
         }
diff --git a/app/src/main/java/com/example/tampopo_client/views/LogoutActivity.java b/app/src/main/java/com/example/tampopo_client/views/LogoutActivity.java
index 35b0561..f62b98c 100644
--- a/app/src/main/java/com/example/tampopo_client/views/LogoutActivity.java
+++ b/app/src/main/java/com/example/tampopo_client/views/LogoutActivity.java
@@ -40,7 +40,7 @@
         Button logoutbutton = (Button) findViewById(R.id.logoutbutton);
         logoutbutton.setOnClickListener(new View.OnClickListener() {
             public void onClick(View v) {
-                Intent intent = new Intent(LogoutActivity.this, SettingActivity.class);
+                Intent intent = new Intent(LogoutActivity.this, LaunchActivity.class);
                 startActivity(intent);
             }
         });
diff --git a/app/src/main/java/com/example/tampopo_client/views/ProfileActivity.java b/app/src/main/java/com/example/tampopo_client/views/ProfileActivity.java
index 075b7ff..3d16dc4 100644
--- a/app/src/main/java/com/example/tampopo_client/views/ProfileActivity.java
+++ b/app/src/main/java/com/example/tampopo_client/views/ProfileActivity.java
@@ -43,9 +43,12 @@
         EditText nicknameInput = (EditText) findViewById(R.id.nicknamebutton);
         nicknameInput.setText(((Tampopo) ProfileActivity.this.getApplication()).getNickname());
 
-        EditText useridInput = (EditText) findViewById(R.id.idbutton);
+        EditText useridInput = findViewById(R.id.idbutton);
         useridInput.setText(((Tampopo) ProfileActivity.this.getApplication()).getUserId());
 
+        //IDを変更できないようにする
+        useridInput.setEnabled(false);
+
 
         //決定ボタンを押したときにidとニックネームを保存
         Button dicisionbutton = findViewById(R.id.dicisionbutton);
@@ -58,7 +61,7 @@
                 EditText useridInput = findViewById(R.id.idbutton);
                 String userid = useridInput.getText().toString();
 
-                // Application（Tampopo）に保存（→SharedPreferencesにも自動保存される）
+                // Application（Tampopo）に保存
                 Tampopo app = (Tampopo) getApplication();
                 app.setNickname(usernickname);
                 app.setUserId(userid);