@@ -0,0 +1,154 @@
+package com.byndyusoft.calculator;%0A%0A/**%0A * Created by fedor on 27.02.17.%0A */%0A%0Apublic interface CalculatorView %7B%0A%0A    void updateScreen(String content);%0A%7D%0A

Add CalculatorView interface to define contract between View and Presenter