diff --git a/app/src/main/java/org/ntlab/amaryllis/client/MainActivity.java b/app/src/main/java/org/ntlab/amaryllis/client/MainActivity.java
index 32e21ef..28a99cb 100644
--- a/app/src/main/java/org/ntlab/amaryllis/client/MainActivity.java
+++ b/app/src/main/java/org/ntlab/amaryllis/client/MainActivity.java
@@ -28,11 +28,18 @@
 
 import com.google.android.material.bottomnavigation.BottomNavigationView;
 
+import org.ntlab.amaryllis.client.entities.Category;
 import org.ntlab.amaryllis.client.fragment.MapsFragment;
 import org.ntlab.amaryllis.client.resources.AccountsRest;
+import org.ntlab.amaryllis.client.resources.CategoriesRest;
 
 import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
 
+import retrofit2.Call;
+import retrofit2.Callback;
+import retrofit2.Response;
 import retrofit2.Retrofit;
 import retrofit2.converter.jackson.JacksonConverterFactory;
 
@@ -42,6 +49,7 @@
     private static final String TAG = MainActivity.class.getSimpleName();
     LocationManager locationManager;
     private ArrayList<LocationListener> listeners = new ArrayList<>();
+    private HashMap<String ,Category> categories;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -56,6 +64,29 @@
         NavigationUI.setupActionBarWithNavController(this, navController, appBarConfiguration);
         NavigationUI.setupWithNavController(navView, navController);
 
+        Retrofit retrofit = new Retrofit.Builder()
+                .baseUrl("http://nitta-lab-www.is.konan-u.ac.jp/amaryllis/")
+                .addConverterFactory(JacksonConverterFactory.create())
+                .build();
+        final CategoriesRest categoryService = retrofit.create(CategoriesRest.class);
+        Call<List<Category>> call = categoryService.getcategories();
+        call.enqueue(new Callback<List<Category>>() {
+            @Override
+            public void onResponse(Call<List<Category>> call, Response<List<Category>> response) {
+                List<Category> clist = response.body();
+                HashMap<String ,Category> categories = new HashMap<>();
+                for (Category c : clist){
+                    categories.put(c.getcId(),c);
+                }
+                MainActivity.this.categories = categories;
+            }
+
+            @Override
+            public void onFailure(Call<List<Category>> call, Throwable t) {
+
+            }
+        });
+
 
         LocationManager manager = (LocationManager) getSystemService(LOCATION_SERVICE);
         if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
@@ -63,6 +94,7 @@
         }
         manager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
     }
+
     private void locationStart(){
         Log.d("debug","locationStart()");
 
@@ -160,4 +192,8 @@
         android.os.Process.killProcess(android.os.Process.myPid());
     }
 
+    public Category getCategory(String cid){
+        return categories.get(cid);
+    }
+
 }
\ No newline at end of file