Problems with Instance Variable in Controllenr

I've got problems with an instance variable in a controller. the varible is initialized and has some entries which i give out in the second view(create). but in the third view (export) I become back this message: ...............ActionView::Template::Error (undefined method `length' for nil:NilClass):     1: <%=@month_issues.class%>     2: <%=@month_issues.length%>     3: <%@month_issues.each do |mi|%>     4: <%= mi.text %>     5: <%end%>   plugins/abrechnung/app/views/abrechnung/export.html.erb:2:in `_plugins_abrechnung_app_views_abrech nung_export_html_erb___625827306_55588872'............. But in abrechnung_controller the vaiable is initialised as Array with some antries, how it can be nil?

Attachments: http://www.ruby-forum.com/attachment/10248/abrechnung_controller.rb http://www.ruby-forum.com/attachment/10249/month_issue.rb http://www.ruby-forum.com/attachment/10250/export.html.erb http://www.ruby-forum.com/attachment/10251/routes.rb

You realize instance variables are not carried forward from one action to another? They have to be set up on each request.