http://snippets.dzone.com/posts Mon, 06 Oct 2008 14:49:22 GMT DZone Snippets: acts_as_tree code http://snippets.dzone.com/posts/show/4388 // This takes a collection of acts_as_tree objects and creates a unordered list. <br />// <br />// Put this in your helper: <br /> <br /><code> <br /> def tree_ul(acts_as_tree_set, init=true, &block) <br /> if acts_as_tree_set.size > 0 <br /> ret = '<ul>' <br /> acts_as_tree_set.collect do |item| <br /> next if item.parent_id && init <br /> ret += '<li>' <br /> ret += yield item <br /> ret += tree_ul(item.children, false, &block) if item.children.size > 0 <br /> ret += '</li>' <br /> end <br /> ret += '</ul>' <br /> end <br /> end <br /></code> <br /> <br />// ... and this in your view: <br /><code> <br /> <%= tree_ul(@acts_as_list_collection) {|item| link_to h(item.name), :action => 'edit', :id => item } %> <br /></code> Sat, 04 Aug 2007 17:46:08 GMT http://snippets.dzone.com/posts/show/4388 goodieboy (Matt Mitchell) http://snippets.dzone.com/posts/show/1919 You should have a categories table with a parent_id field. Root categories should have the parent_id of 0. <br /> <br />I modified this post: <br />http://www.bigbold.com/snippets/posts/show/296 <br /> <br />because the first one worked if you did stuff in your view to make the root categories come up, but I agree with the commenter that things should be contained to the helper - however I've managed to break the DRY rule in doing so. If anyone has any suggestions for a better way around this I'd love to hear it, so please comment. So anyway.. this should list your root categories ONLY and NOT your other sub-cats as well so that you have a very pretty little tree. <br /> <br />Slap this in your view: <br /> <br /><code> <br /><%= display_categories(@categories) %> <br /></code> <br /> <br />And put this in a helper file. You'll need it in the application helper most likely since you'll want to call it from multiple views. <br /> <br /><code> <br /> def display_categories(categories) <br /> ret = "<ul>" <br /> for category in categories <br /> if category.parent_id == 0 <br /> ret += "<li>" <br /> ret += link_to category.name <br /> ret += find_all_subcategories(category) <br /> ret += "</li>" <br /> end <br /> <br /> end <br /> ret += "</ul>" <br /> end <br /> <br /> def find_all_subcategories(category) <br /> if category.children.size > 0 <br /> ret = '<ul>' <br /> category.children.each { |subcat| <br /> if subcat.children.size > 0 <br /> ret += '<li>' <br /> ret += link_to h(subcat.name), :action => 'edit', :id => subcat <br /> ret += find_all_subcategories(subcat) <br /> ret += '</li>' <br /> else <br /> ret += '<li>' <br /> ret += link_to h(subcat.name), :action => 'edit', :id => subcat <br /> ret += '</li>' <br /> end <br /> } <br /> ret += '</ul>' <br /> end <br /> end <br /></code> Sun, 16 Apr 2006 15:32:57 GMT http://snippets.dzone.com/posts/show/1919 ioda006 () http://snippets.dzone.com/posts/show/296 In your view: <br /><code> <br /><ul> <br /><% for category in @categories %> <br /> <li><%= link_to h(category.title), :action => 'edit', :id => category %> <br /> <%= find_all_subcategories(category) %> <br /> </li> <br /><% end %> <br /></ul> <br /></code> <br /> <br />Place this in a helper: <br /><code> <br /> def find_all_subcategories(category) <br /> if category.children.size > 0 <br /> ret = '<ul>' <br /> category.children.each { |subcat| <br /> if subcat.children.size > 0 <br /> ret += '<li>' <br /> ret += link_to h(subcat.title), :action => 'edit', :id => subcat <br /> ret += find_all_subcategories(subcat) <br /> ret += '</li>' <br /> else <br /> ret += '<li>' <br /> ret += link_to h(subcat.title), :action => 'edit', :id => subcat <br /> ret += '</li>' <br /> end <br /> } <br /> ret += '</ul>' <br /> end <br /> end <br /></code> Wed, 18 May 2005 14:54:12 GMT http://snippets.dzone.com/posts/show/296 Caged (Justin Palmer)