Gaikan gives you powerful styling capabilities using a declarative DSL in Swift. Inspired by React: CSS in JS and CSS modules.

To style UIView(s) just give them a StyleRule object:

let myLabelStyle = StyleRule() { (inout style: StyleRule) -> () in
  style.color = UIColor.redColor()
  style.border = Border(width: 1, color: UIColor.greenColor())
  style.font = UIFont(name: "Courier", size: 24)
}

self.label.styleInline = myLabelStyle

Check out the sample to see how to well integrate Gaikan into a project.

Features

• Apply a simple style using styleInline….
• … or make theming using styleClass (see below for more information).
• You can share styles using extends method to avoid repeating yourself.
• You can style depending on your control state (enabled, highlighted, …).
• You can style NSAttributedString!

Properties

Check out our page on properties to find which one to use to style your views.

Starting with 0.4, we also added VirtualView. This allow you to apply style effects on some non UIView attributes/objects:

Advanced usage

NSAttributedString

Just call NSAttributedString(string:"Hello", style: yourStyle) to get a styled NSAttributedString.

Alternatively you can use style.textAttributes to transform StyleRule into any NSAttributedString compatible dictionary.

Theme

Theme packages together multiple Style definitions to make a whole set.

public class SampleTheme : Theme {
  /// Non static is important if you want to reference them from InterfaceBuilder
  lazy let logo = Style(...)
  lazy let title = Style(...)
}

class CustomView: UIView {
  typealias ThemeType = RailTheme

  @IBOutlet weak var title: UILabel!
  @IBOutlet weak var footnote: UILabel!
  @IBOutlet weak var logo: UIImageView!
  @IBOutlet weak var button: UIButton!

  override func awakeFromNib() {
    self.title.styleClass = SampleTheme().logo
    self.logo.styleClass = SampleTheme().title
  }
}

You can also apply themes right from InterfaceBuilder:

Extends

You can extend your styles to reuse common features:

func primary() -> Style {
  return [
    .Color: UIColor.greenColor()
  ]
}

func large() -> Style {
  return [
    .Font: UIFont.systemFontOfSize(18)
  ]
}

func merged() -> Style {
  return Style().extends(primary(), large())
  // color: green, font: 18
}

States

You can define styles for states. They’ll extend from the default state :

func style() -> Style {
  return Style() { (inout style: StyleRule) -> Void in
    style.tintColor = UIColor.whiteColor()
  }
  .state(.Selected, attributes: [
      .TintColor: UIColor.grayColor().colorWithAlphaComponent(0.6)
  ]
}

Don’t hesitate to take a look at the sample to better understand how it works.

Contributing

This project was first developed by Xebia IT Architects in Paris, France. We will continue working and investing on it.

We encourage the community to contribute to the project by opening tickets and/or pull requests. Here a some of the subjects we are interested in:

• Add UIStackView attributes (distribution, spacing, …).
• Support for multiple layout engines (AutoLayout, LayoutKit, Flexbox, …)
• Allow to define 1+ borders and corner radius. Currently defining border and radius set the 4 of them (top, bottom, left, right).
• Better support for IBDesignable (if possible).
• Add debugging information (style name, inheritance, …).
• Better integration with NSAttributedString.
• Support for traits.
• Anything you have in mind!

License

Gaikan is released under the MIT License. Please see the LICENSE file for details.