diff --git a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
index 37e4b67..bd93bbe 100644
--- a/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
+++ b/app/src/main/java/org/ntlab/developrx/JavaMainActivity.java
@@ -18,5 +18,6 @@
         findViewById(R.id.observable_btn).setOnClickListener(view -> rxProcess.observable());
         findViewById(R.id.just_btn).setOnClickListener(view -> rxProcess.just());
         findViewById(R.id.fromarray_btn).setOnClickListener(view -> rxProcess.fromArray());
+        findViewById(R.id.range_btn).setOnClickListener(view -> rxProcess.range());
     }
 }