Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/indragiek/SwiftAutoLayout
Tiny Swift DSL for Autolayout
https://github.com/indragiek/SwiftAutoLayout
Last synced: about 1 month ago
JSON representation
Tiny Swift DSL for Autolayout
- Host: GitHub
- URL: https://github.com/indragiek/SwiftAutoLayout
- Owner: indragiek
- License: mit
- Created: 2014-06-18T04:44:04.000Z (over 10 years ago)
- Default Branch: master
- Last Pushed: 2021-09-11T01:31:23.000Z (over 3 years ago)
- Last Synced: 2024-10-13T17:48:19.468Z (3 months ago)
- Language: Swift
- Size: 71.3 KB
- Stars: 655
- Watchers: 23
- Forks: 44
- Open Issues: 9
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
- awesome-ios - SwiftAutoLayout - Tiny Swift DSL for Autolayout. (Layout / Other Hardware)
- awesome-ios-star - SwiftAutoLayout - Tiny Swift DSL for Autolayout. (Layout / Other Hardware)
- awesome-swift-cn - SwiftAutoLayout - a small DSL for autolayout. (Libs / Layout)
README
## SwiftAutoLayout
SwiftAutoLayout is a tiny DSL for Autolayout intended to provide a more declarative way to express layout constraints. Here's a quick example:
```swift
// this:
let constraint = view1.left == view2.right * 2.0 + 10.0 ~ 750
// is equivalent to:
let constraint = NSLayoutConstraint(item: view1, attribute: NSLayoutAttribute.Left, relatedBy: NSLayoutRelation.Equal, toItem: view2, attribute: NSLayoutAttribute.Right, multiplier: 2.0, constant: 10.0)
constraint.priority = 750
```
You may notice that this looks a lot like the linear equation that a constraint represents. From the [Apple documentation](https://developer.apple.com/library/mac/documentation/AppKit/Reference/NSLayoutConstraint_Class/NSLayoutConstraint/NSLayoutConstraint.html):
> The relationship involves a first attribute, a relationship type, and a modified second value formed by multiplying an attribute by a constant factor and then adding another constant factor to it. In other words, constraints look very much like linear equations of the following form:
>
> `attribute1 == multiplier × attribute2 + constant`
SwiftAutoLayout allows you to more effectively communicate the intent of a constraint by making the syntax more similar to the equation that it represents.
### Installing
Use [Swift Package Manager](https://github.com/apple/swift-package-manager) or add `SwiftAutoLayout.xcodeproj` as a subproject and link against either `SwiftAutoLayout-iOS.framework` or `SwiftAutoLayout-Mac.framework` depending on the platform.
### Attributes
Layout attributes are defined as properties added in extensions of `UIView` and `UILayoutGuide` on iOS and `NSView` and `NSLayoutGuide` on OS X. For example, `UIView.width` and `UIView.height` represent `NSLayoutAttribute.Width` and `NSLayoutAttribute.Height`, respectively.
Layout guides (conforming to `UILayoutSupport`) in `UIViewController` are also supported using the `topLayoutGuideTop`, `topLayoutGuideBottom`, `bottomLayoutGuideTop`, and `bottomLayoutGuideBottom` properties.
### Relations
Relations are expressed using the overloaded operators `==` (`NSLayoutRelation.Equal`), `>=` (`NSLayoutRelation.GreaterThanOrEqual`), and `<=` (`NSLayoutRelation.LessThanOrEqual`).
### Examples
#### Activating Single Constraint
```swift
(view1.left == view2.right * 2.0 + 10.0 ~ 750).active = true
```
#### Activating Multiple Constraints
```swift
NSLayoutConstraint.activateConstraints([
view2.centerX == view2.superview!.centerX,
view2.centerY == view2.superview!.centerY,
view1.left == view2.right * 2.0 + 10.0 ~ 750,
view1.top == view2.bottom + 5.0,
view1.width >= 200,
view1.height >= 400,
view1.trailing == layoutGuide.trailing,
view2.leading == layoutGuide.leading
])
```
### Contact
* Indragie Karunaratne
* [@indragie](http://twitter.com/indragie)
* [http://indragie.com](http://indragie.com)
### License
SwiftAutoLayout is licensed under the MIT License.