Latest 2.1.1
License MIT
Platforms ios 8.0


uses some swift amazing feature, provides a very short and clear way to make constraints in code.

XCode 8 and above

since swift 3 is reqiured, you need XCode 8 and above.
if you seek swift 2.3 version, use 1.3.0 instead.

Latest version

current latest version is 2.1.1.

Quick look

you must know what ‘left.attr = right.attr * m + c’ means for AutoLayout.

import XAutoLayout

// use `=/`` to make composite equal witch creates an array of NSLayoutConstraint
NSLayoutConstraint.activateConstraints( v1.xEdge =/ [10,5,-10,-20] )

// use 'xmakeConstraints' to make constraints. constraints can be adjusted by 'direction'
// direction is default to 'LeadingToTrailing' and autoActive is default to 'true' 
xmakeConstraints(.RightToLeft, autoActive: true) {
    v2.xSize =/ [50, view.xHeight.xc(-80)]
    // since the direction is 'RightToLeft', the "v2.xLeading =/ 10" will be adjusted as "v2.xRight =/ -10"
    [v2.xTop, v2.xLeading] =/ [20, 10.xp(750)]
    // notice that in 'v2.xLeading =/ 10' the right var is a number 10, 
    // since no view is specified, superview of v2 will be used as second item, and secondAttr is same as firstAttr.
    // so the result is same as "v2.xLeading =/ v2.superview.xLeading.c(10)"

// and you should know "v.xHeight =/ 20" will not use superview, because height and width are dimension not anchor.

// we can also adjust constraint's constaint, multiplier and priority
v.xWidth =/ view.xWidth.xm(2).xc(-20).xp(750)

It’s easy to read and write. isn’t it?

support your type

  1. first item
    you need to confirm to XFirstItem protocol and implement xGenerate.

    func xGenerate() -> XAttribute {
    return XAttribute(item: yourItem, attr: yourAttr)

    yourItem and yourAttr are the item and attr which will be constraint’s firstItem and firstAttr.

  2. second item
    look at the SignedNumberType’s and UnsignedIntegerType’s implementation.

    public func xGenerateX() -> XAttributeX {
    return XAttributeX(item: nil, attr: .NotAnAttribute, constant: CGFloat(("(self)" as NSString).doubleValue))

    item and attr will be constraint’s secondItem and secondAttr.
    you can provide constant, multiplier and priority if you need. but you must know what you are doing.

What’s the matter of AutoLayout ?

The API is not friendly for developers. Too long and too complicated. wish XAutoLayout will make our lives easier.

Latest podspec

    "name": "XAutoLayout",
    "version": "2.1.1",
    "summary": "simplify writing AutoLayout in code. better direction handling.",
    "homepage": "",
    "license": {
        "type": "MIT",
        "file": "LICENSE"
    "authors": {
        "kaizei": "[email protected]"
    "platforms": {
        "ios": "8.0"
    "source": {
        "git": "",
        "tag": "2.1.1"
    "source_files": "XAutoLayout/codes/**/*.swift",
    "pushed_with_swift_version": "3.0"

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