SnapKitten is a Linear Layout Solution Library based on SnapKit and Auto Layout.
To run the example project, clone the repo, and run pod install from the Example directory first.
import UIKit import SnapKitten import PlaygroundSupport let virtualView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 480)) virtualView.backgroundColor = UIColor.gray PlaygroundPage.current.liveView = virtualView // ... some init UI Code let simpleComponent = Kitten.horizontal().from() .add(iv).size(40) .add(lblA).itemOffset(10) .build() simpleComponent.backgroundColor = UIColor.green let threeComponentExample = Kitten.horizontal() .from().isAlignDirectionEnd(true).defaultAlignment(.center) .add(iv2).size(40) .add(lbl2).fillParent() .add(iv3).size(60) .build() threeComponentExample.backgroundColor = UIColor.orange Kitten.create(.vertical).from(virtualView) .add(simpleComponent).align(.start) .add(threeComponentExample) .build()Result: 
Kitten is a constraint relation building library under SnapKitten and iOS Constraint system. Kitten build the constraint relation between views and result in a Android LinearLayout-Like behaviour.
Kitten simplify the complex constraint system set-up and break it down to few simple linear relationship.
To create Kitten Object, it need to know the orientation in the beginning
//Kitten's method always return Protocol, but you can always force cast to Kitten itself Kitten.horizontal() Kitten.vertical()You may want to add views to a existing view. or Just create a new one. Kitten support ScrollView, View, UIViewController and dyanmic create a new one. for UIViewController, it default align topLayoutGuide and bottomLayoutGuide
//all return KittenParentMethods protocol Kitten.vertical().from() Kitten.vertical().from(scrollView) Kitten.vertical().from(viewController) Kitten.vertical().from(view)You can now setup basic setting after from() method. KittenParentMethods protocol provides some method for you layout basic setup.
//.center, .start, .end, .parent defaultAlignment(enum)//a perpendicular alignment of child views startPadding(int)//offset with first item and parent endPadding(int)//offset with last item and parent itemDefaultOffset(int) //offset between item itemDefaultSideStartPadding(int)//perpendicular offset, always top or left itemDefaultSideEndPadding(int) //perpendicualr offset, always bottom or right itemDefaultSidePadding(int) allPadding(int)//all four direction padding, except item-to-item isAlignDirectionEnd(bool) //determine if last child align parent's end. Like match_parent in LinearLayout weightMode(bool) // change to weightMode, child's size based on the weight related to parent, usually use with isAlignDirectionEnd(true)you can always add a view to Kitten or find existing view with KittenChild protocol.
add(UIView)//add a child to Kitten, following KittenChildMethods is updating this child view with(UIView)//find existing child, and update it in following method call addChilds(UIView ...) addChilds([UIView])after add your child, you may need to provide some information about this view
itemOffset(int)//a offset to previous item, for first child, it will not be active sideStartPadding(int)//a perpendicular padding of item, left or top sideEndPadding(int)//right or bottom sidePadding(int) width(int)//set the width of view height(int)//set the height of view size(int)//set the size of view alignSideStart()//align the parent start, top / left alignSideEnd()//align parent end, bottom / right alignSideCenter()//align center of parent, depend on orientation alignSideParent()//child align parent's width / height fillParent()//a child try to fit the size to parent as possible importanceHigh()//the importance of child, higher importance, it will not be compress if other view is big to fillup the parent orientation importanceMedium() importanceLow() weight(float)//active in weightMode(true) only, it determine the weight of item, default is 1.You must build the constraint after adding all children into Kitten class build() and rebuild() return the parent UIView which contain children
build() //will not remove subview / its constraint relation rebuild() // remove subviews before build()Kitten methods always return "Protocol" but you can always force cast to Kitten object
let kitten : Kitten = Kitten.horizonta() as! Kitten let kitten : Kitten = Kitten.horizonta().from() as! Kitten let kitten : Kitten = Kitten.horizonta().from().add(lblA) as! KittenAs kitten is a linear relationship, children do not have actual relation to specific item Kitten provides a condition method to allow the control of child insertion
let threeComponentExample = Kitten.horizontal() .from().isAlignDirectionEnd(true).defaultAlignment(.center) .add(iv2).size(40) .add(lbl2).fillParent() .add(iv3).size(60).condition({ () -> Bool in // you can determine the condition by any variable in your class return false }) .rebuild()
You can always visualize test your code in iOS Playground To open visual playground, Click "View > Assistant Editor > Show Assisant Editor" in Xcode
import UIKit import SnapKitten import PlaygroundSupport let virtualView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 100)) virtualView.backgroundColor = UIColor.gray PlaygroundPage.current.liveView = virtualView let iv = UIImageView() iv.backgroundColor = UIColor.red let lblA = UILabel() lblA.text = "Hello World" lblA.backgroundColor = UIColor.blue let simpleComponent = Kitten.horizontal().from() .add(iv).size(40) .add(lblA).itemOffset(10) .build() simpleComponent.backgroundColor = UIColor.green Kitten.create(.vertical).from(virtualView) .add(simpleComponent).align(.start) .build()
- iOS 8.0+
SnapKitten is available through CocoaPods. To install it, simply add the following line to your Podfile:
pod "SnapKitten"Spring, development.spring@gmail.com
SnapKitten is available under the MIT license. See the LICENSE file for more info.