registering events with objects not procs

to make unregistering easier

app/block_view.rb

@@ -6,17 +6,27 @@ class BlockView
   include React::Component
   required_param :interpreter
 
+  before_mount do
+    interpreter.register_event(event: :block_changed, listener: self, callback: :block_changed)
+  end
+
+  def block_changed block
+    block! block
+  end
 
   def render
     div.row  do
-      div.col_md_6 do
+      div.col_md_5 do
         SourceView  :source => interpreter.block.codes.first.source
       end
-      div.col_md_6 do
+      div.col_md_5 do
         interpreter.block.codes.each do |code|
           code.to_s.br
         end
       end
+      div.col_md_2 do
+        button.btn.btn_default { "next" }.on(:click) { interpreter.tick }
+      end
     end
   end
 end