diff --git a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
index ac684e7..b029fc4 100644
--- a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
+++ b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
@@ -24,6 +24,7 @@
         findViewById(R.id.error_btn).setOnClickListener(view -> rxProcess.error());
         findViewById(R.id.map_btn).setOnClickListener(view -> rxProcess.map());
         findViewById(R.id.empty_btn).setOnClickListener(view -> rxProcess.empy());
-        findViewById(R.id.flatmap_btn).setOnClickListener(view -> rxProcess.flatmap());
+        findViewById(R.id.flatmap_1_btn).setOnClickListener(view -> rxProcess.flatmap1());
+        findViewById(R.id.flatmap_2_btn).setOnClickListener(view -> rxProcess.flatmap2());
     }
 }