Awesome
Class variants
We ❤️ Tailwind CSS but sometimes it's difficult to manage the state of some elements using conditionals. class_variants
is a tiny helper that should enable you to create, configure, and apply different variants of elements as classes.
Inspired by variant-classnames ✌️
Quicklinks
Installation
Add this line to your application's Gemfile:
gem 'class_variants'
And then execute:
$ bundle
Or install it yourself as:
$ gem install class_variants
Usage
We create an object from the class or helper where we define the configuration using four arguments:
- The
base
keyword argument with default classes that should be applied to each variant. - The
variants
keyword argument where we declare the variants with their option and classes. - The
compound_variants
keyword argument where we declare the compound variants with their conditions and classes - The
defaults
keyword argument (optional) where we declare the default value for each variant.
Below we'll implement the button component from Tailwind UI.
# Define the variants and defaults
button_classes = ClassVariants.build(
base: "inline-flex items-center rounded border border-transparent font-medium text-white hover:text-white shadow-sm focus:outline-none focus:ring-2 focus:ring-offset-2",
variants: {
color: {
indigo: "bg-indigo-600 hover:bg-indigo-700 focus:ring-indigo-500",
red: "bg-red-600 hover:bg-red-700 focus:ring-red-500",
blue: "bg-blue-600 hover:bg-blue-700 focus:ring-blue-500",
},
size: {
sm: "px-2.5 py-1.5 text-xs",
md: "px-3 py-2 text-sm",
lg: "px-4 py-2 text-sm",
xl: "px-4 py-2 text-base",
},
compound_variants: [
{ color: :red, border: true, class: "border-red-800" },
{ color: :blue, border: true, class: "border-blue-800" }
]
# A variant whose value is a string will be expanded into a hash that looks
# like { true => "classes" }
icon: "w-full justify-center",
# Unless the key starts with !, in which case it will expand into
# { false => "classes" }
"!icon": "w-auto",
},
defaults: {
size: :md,
color: :indigo,
icon: false
}
)
# Call it with our desired variants
button_classes.render(color: :blue, size: :sm)
button_classes.render
button_classes.render(color: :red, size: :xl, icon: true)
Compound Variants
button_classes = ClassVariants.build(
base: "inline-flex items-center rounded",
variants: {
color: {
red: "bg-red-600",
blue: "bg-blue-600",
},
border: "border"
},
compound_variants: [
{ color: :red, border: true, class: "border-red-800" },
{ color: :blue, border: true, class: "border-blue-800" }
]
)
button_classes.render(color: :red) # => "inline-flex items-center rounded bg-red-600"
button_classes.render(color: :red, border: true) # => "inline-flex items-center rounded bg-red-600 border border-red-600"
Override classes with render
We can also override the builder classes in the render
method.
button_classes = ClassVariants.build(
base: "inline-flex items-center rounded",
variants: { ... },
)
button_classes.render(color: :red, class: "block")
Now, the block
class will be appended to the classes bus.
If you're using the tailwind_merge
plugin it will override the inline-flex
class.
Block configurations
You might have scenarios where you have more advanced conditionals and you'd like to configure the classes using the block notation.
alert_classes = ClassVariants.build do
# base
base "..."
# variant
variant color: :red, class: "..."
# compound variant
variant type: :button, color: :red, class: "..."
# defaults
defaults color: :red, type: :button
end
# usage
alert_classes.render(color: :red, type: :button)
Slots
You might have components which have multiple slots or places where you'd like to use conditional classes.
class_variants
supports that through slots.
# Example
alert_classes = ClassVariants.build do
# base with slots
base do
slot :head, class: "..."
slot :body, class: "..."
end
# variant with slots
variant color: :red do
slot :head, class: "..."
slot :body, class: "..."
end
# compound variant with slots
variant type: :button, color: :red do
slot :head, class: "..."
slot :body, class: "..."
end
# set defaults
defaults color: :red, type: :button
end
<div>
<div class="<%= alert_classes.render(:head) %>">
Head of alert
</div>
<div class="<%= alert_classes.render(:body) %>">
Body of alert
</div>
</div>
Full API
# Configuration
alert_classes = ClassVariants.build(
base: "...",
variants: {
color: {
red: "...",
black: "..."
},
type: {
button: "...",
link: "..."
}
},
compound_variants: [],
defaults: {
color: :red,
type: :button
}
) do
# base without slots
base "..."
# base with slots
base do
slot :head, class: "..."
slot :body, class: "..."
end
# variant without slots
variant color: :red, class: "..."
# variant with slots
variant color: :red do
slot :head, class: "..."
slot :body, class: "..."
end
# compound variant without slots
variant type: :button, color: :red, class: "..."
# compound variant with slots
variant type: :button, color: :red do
slot :head, class: "..."
slot :body, class: "..."
end
# option 1 (my favorite)
defaults color: :red, type: :button
# option 2
defaults do
color :red
type :button
end
end
# Usage
# renders the defaults
alert_classes.render
# render default slot with custom variants
alert_classes.render(color: :red)
# render slot with defaults variants
alert_classes.render(:body)
# render slot with custom variants
alert_classes.render(:body, color: :red)
# if slot not exist, throw error? return empty classes?
alert_classes.render(:non_existent_slot, color: :red)
# render default slot with custom class (will be merged)
alert_classes.render(class: "...")
# render slot with custom class (will be merged)
alert_classes.render(:body, class: "...")
Use with Rails
# Somewhere in your helpers
def button_classes(classes, **args)
class_variants(
base: "inline-flex items-center rounded border border-transparent font-medium text-white hover:text-white shadow-sm focus:outline-none focus:ring-2 focus:ring-offset-2",
variants: {
size: {
sm: "px-2.5 py-1.5 text-xs",
md: "px-3 py-2 text-sm",
lg: "px-4 py-2 text-sm",
xl: "px-4 py-2 text-base",
},
color: {
indigo: "bg-indigo-600 hover:bg-indigo-700 focus:ring-indigo-500",
red: "bg-red-600 hover:bg-red-700 focus:ring-red-500",
blue: "bg-blue-600 hover:bg-blue-700 focus:ring-blue-500",
},
},
defaults: {
size: :md,
color: :indigo,
}
)
end
<!-- In your views -->
<%= link_to :Avo, "https://avohq.io", class: button_classes.render(color: :blue, size: :sm) %>
<%= link_to :Avo, "https://avohq.io", class: button_classes.render %>
<%= link_to :Avo, "https://avohq.io", class: button_classes.render(color: :red, size: :xl) %>
Helper module
If you're developing something more complex you might want to use composition more. You might want to use the helper module for that.
class MyClass
include ClassVariants::Helper
class_variants {
base: {},
variants: {}
}
end
MyClass.new.class_variants(:container, color: :red, class: "shadow")
tailwind_merge
By default, the classes are merged using concat
, but you can use the awesome TailwindMerge gem.
Install the gem using bundle add tailwind_merge
and use this configuration to enable it.
ClassVariants.configure do |config|
config.process_classes_with do |classes|
TailwindMerge::Merger.new.merge(classes)
end
end
Output
Other packages
active_storage-blurhash
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- The easiest way to add confetti to your StimulusJS app
Try Avo ⭐️
If you enjoyed this gem try out Avo. It helps developers build Internal Tools, Admin Panels, CMSes, CRMs, and any other type of Business Apps 10x faster on top of Ruby on Rails.
Contributing
- Fork it
git clone https://github.com/avo-hq/class_variants
- Create your feature branch
git checkout -b my-new-feature
- Commit your changes
git commit -am 'Add some feature'
- Push to the branch
git push origin my-new-feature
- Create new Pull Request
License
This package is available as open source under the terms of the MIT License.
Cutting a release
# Build
gem build class_variants.gemspec -o latest.gem
# Publish
gem push --host https://rubygems.org/ ./latest.gem
# Cut a tag
git tag v0.0.6 -a -m "Version 0.0.6"
# Push tag to repo
git push --follow-tags
# Go to the repo and generate release from tag