Ruby on Rails中的动作控制器异常

Question

THIS IS THE VIEW FILE FOR SHOW METHOD: it is a simple project for adding movie with its review,ticket count and displaying it. I get an error in the #3 line. Pls help me with it.

error :You have a nil object when you didn't expect it! The error occurred while evaluating nil.name

<h1><%= @movie.title %></h1>
<p><strong>Ticket count: </strong> $<%= @movie.ticket_count %><br />
<strong>Language: </strong> <%= link_to @movie.language.name, :action => "show_lang",      :id => @movie.language.id %><br />
<strong>Created Date:</strong> <%= @movie.created_at %><br />
</p>
<p><%= @movie.review %></p>
<hr />
<%= link_to 'Back', {:action => 'list'} %>

Answer 1

@movie.language is nil. make sure the language is set for the movie.

The best practice is to use delegate in Movie

For more information:

According to the law of demeter, a model should only talk to its immediate association, don't talk to the association's association and association's property, it is a case of loose coupling.

http://rails-bestpractices.com/posts/15-the-law-of-demeter