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PORuby on Rails: How to use a local variable in a collection_select
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  1. PORuby on Rails: How to use a local variable in a collection_select
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    copied!<p>I'm trying to create a &lt;select&gt; element using the collection_select method, but it seems that in order for the proper &lt;option&gt; to be selected, the identifier passed into collection_select needs to be an instance variable and not a local variable (this is happening in a partial).</p> <p>So when I create a &lt;select&gt; for the <code>categories</code> of a <code>product</code>, the proper category is NOT selected by default.</p> <p>_product_row.erb (DOES NOT WORK):</p> <pre><code>My product: &lt;%= product.name %&gt; &lt;%= collection_select(:product, :category_id, @current_user.categories, :id, :name, options = {:prompt =&gt; "-- Select a category --"}) %&gt; </code></pre> <p>Screenshot:</p> <p><a href="http://img534.imageshack.us/img534/8929/screenshot20100421at120.png" rel="nofollow noreferrer">alt text http://img534.imageshack.us/img534/8929/screenshot20100421at120.png</a></p> <p>I discovered that I was able to get it to work by declaring an instance variable before hand, but this seems like a huge hack to me.</p> <p>_product_row.erb (WORKS):</p> <pre><code>&lt;% @product_select_tmp = product %&gt; &lt;%= collection_select(:product_select_tmp, :category_id, @current_user.categories, :id, :name, options = {:prompt =&gt; "-- Select a category --"}) %&gt; </code></pre> <p>Screenshot:</p> <p><a href="http://img534.imageshack.us/img534/1958/screenshot20100421at120l.png" rel="nofollow noreferrer">alt text http://img534.imageshack.us/img534/1958/screenshot20100421at120l.png</a></p> <p>Because this partial is iterating over a collection of products, I can't just have @product declared in the controller (IOW unless I'm missing something, product <em>must</em> be a local variable in this partial).</p> <p>So how do I get collection_select to select the appropriate item when calling it with a local variable?</p>
 

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