add Callback

Author: utsavdotpro

README.md

@@ -24,6 +24,7 @@ Custom interface classes with instantiate, initialize, listen, load functions. W
 
 - Activity
 - BundleBuilder
+- Callback
 - DialogFragment
 - Fragment
 - JSONBuilder

custom/src/main/java/com/isolpro/custom/Callback.java

@@ -0,0 +1,5 @@
+package com.isolpro.custom;
+
+public interface Callback<T> {
+  void exec(T object);
+}