How do I make dynamic ids in Haml?

Solution 1:

There are two ways:

The long form way (define the id as if it were a regular attribute):

.box{:id => "item_#{x}"}

produces this (x is what ever x.to_s evaluates to):

<div class="box" id="item_x">

The short form way:

.box[x]

produces the following assuming x is an instance of item:

<div class="box item" id="item_45">

See the HAML reference for more information.

Solution 2:

You can set the id and class in HAML the following ways

  1. The normal way

    .box.item#item
    
    <div id="item" class="box item"></div>
    
  2. If you need to interpolation you can use this format

    .box{id: "item_#{123}", class: "item_#{123}"}
    
    <div id="item_123" class="box item_123"></div>
    
  3. This format generates the class and id using the object reference

    # app/controllers/items_controller.rb 
    @item = Item.find(123)
    
    .box[@item]
    
    <div id="item_123" class="box item"></div>
    
  4. If you need to prefix something

    .box[@item, :custom]
    
    <div id="custom_item_123" class="box custom_item"></div>
    
  5. If you need a custom class and id generation you need to add the following method to model.

    class CrazyUser < ActiveRecord::Base
      def haml_object_ref
        "customized_item"
      end
    end
    

    And then you will get the customized class

    .box[@item]
    
    <div id="customized_item_123" class="box customized_item"></div>
    

Refer:

  • http://haml.info/docs/yardoc/file.REFERENCE.html#object-reference-
  • http://haml.info/docs/yardoc/file.REFERENCE.html