我一直在坐过山车，爱自动布局和讨厌它。喜欢它的关键似乎是接受以下几点:

接口构建器的编辑和“有帮助的”自动创建约束在大多数情况下几乎无用 创建类别来简化常见操作是一种拯救，因为代码是如此重复和冗长。

也就是说，你正在尝试的不是直接的，在接口构建器中很难实现。这在代码中很简单。这段代码，在viewDidLoad，创建和定位三个标签，你需要他们:

// Create three labels, turning off the default constraints applied to views created in code
UILabel *label1 = [UILabel new];
label1.translatesAutoresizingMaskIntoConstraints = NO;
label1.text = @"Label 1";

UILabel *label2 = [UILabel new];
label2.translatesAutoresizingMaskIntoConstraints = NO;
label2.text = @"Label 2";

UILabel *label3 = [UILabel new];
label3.translatesAutoresizingMaskIntoConstraints = NO;
label3.text = @"Label 3";

// Add them all to the view
[self.view addSubview:label1];
[self.view addSubview:label2];
[self.view addSubview:label3];

// Center them all horizontally
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:label1 attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:label2 attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:label3 attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0]];

// Center the middle one vertically
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:label2 attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0]];

// Position the top one half way up
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:label1 attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:label2 attribute:NSLayoutAttributeCenterY multiplier:0.5 constant:0]];

// Position the bottom one half way down
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:label3 attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:label2 attribute:NSLayoutAttributeCenterY multiplier:1.5 constant:0]];

我说过，这段代码通过UIView中的一些类别方法简化了很多，但为了清晰起见，这里我做了很多。

对于感兴趣的人来说，这个类别在这里，它有一个方法，可以沿着特定的轴均匀地间隔一个视图数组。

我刚刚用乘数特性解决了我的问题。我不确定它是否适用于所有情况，但对我来说，它非常有效。我在Xcode 6.3供你参考。

我最后做的是:

1)首先将我的按钮放置在320px宽度的屏幕上，以我希望它在320px设备上的方式分布。

2)然后我在所有按钮的superview上添加了一个领先的空间约束。

3)然后我修改了前导空间的属性，使常量为0，乘数是x偏移量除以屏幕宽度(例如，我的第一个按钮距离左边缘8px，所以我将乘数设置为8/320)

4)那么这里重要的一步是将约束关系中的第二个Item更改为superview。尾随而不是superview.leading。这很关键，因为superview。在我的例子中，前导为0，后拖为320，所以8/320在320px设备上是8px，然后当父视图的宽度改变为640或其他什么时，视图都以相对于320px屏幕大小的宽度的比例移动。这里的数学比较容易理解。

我想水平对齐5张图片，所以我最终遵循了Mete的反应，但有一点不同。

第一个图像将在容器中水平居中，容器的值为0，乘数为1:5:

第二张图片将在容器中水平居中，容器的值为0，乘数为3:5:

其余的图像也是这样。例如，第五张(也是最后一张)图像将在容器中水平居中，容器值为0，乘数为9:5:

正如梅特所解释的，顺序是1,3,5,7,9，等等。位置遵循相同的逻辑:第一个位置是1，然后是空格，然后是下一个位置3，依此类推。

Here is a solution that will vertically center any number of subviews, even if they have unique sizes. What you want to do is make a mid-level container, center that in the superview, then put all the subviews in the container and arrange them with respect to one another. But crucially you also need to constrain them to the top and bottom of the container, so the container can be correctly sized and centered in the superview. By figuring the correct height from its subviews, the container can be vertically centered.

在本例中，self是位于所有子视图居中的父视图。

NSArray *subviews = @[ (your subviews in top-to-bottom order) ];

UIView *container = [[UIView alloc] initWithFrame:CGRectZero];
container.translatesAutoresizingMaskIntoConstraints = NO;
for (UIView *subview in subviews) {
    subview.translatesAutoresizingMaskIntoConstraints = NO;
    [container addSubview:subview];
}
[self addSubview:container];

[self addConstraint:[NSLayoutConstraint constraintWithItem:container attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual
                                                    toItem:self attribute:NSLayoutAttributeLeft multiplier:1.0f constant:0.0f]];
[self addConstraint:[NSLayoutConstraint constraintWithItem:container attribute:NSLayoutAttributeRight relatedBy:NSLayoutRelationEqual
                                                    toItem:self attribute:NSLayoutAttributeRight multiplier:1.0f constant:0.0f]];
[self addConstraint:[NSLayoutConstraint constraintWithItem:container attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual
                                                    toItem:self attribute:NSLayoutAttributeCenterY multiplier:1.0f constant:0.0f]];

if (0 < subviews.count) {
    UIView *firstSubview = subviews[0];
    [container addConstraint:[NSLayoutConstraint constraintWithItem:firstSubview attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual
                                                             toItem:container attribute:NSLayoutAttributeTop multiplier:1.0f constant:0.0f]];
    UIView *lastSubview = subviews.lastObject;
    [container addConstraint:[NSLayoutConstraint constraintWithItem:lastSubview attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual
                                                             toItem:container attribute:NSLayoutAttributeBottom multiplier:1.0f constant:0.0f]];

    UIView *subviewAbove = nil;
    for (UIView *subview in subviews) {
        [container addConstraint:[NSLayoutConstraint constraintWithItem:subview attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual
                                                                 toItem:container attribute:NSLayoutAttributeCenterX multiplier:1.0f constant:0.0f]];
        if (subviewAbove) {
            [container addConstraint:[NSLayoutConstraint constraintWithItem:subview attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual
                                                                     toItem:subviewAbove attribute:NSLayoutAttributeBottom multiplier:1.0f constant:10.0f]];
        }
        subviewAbove = subview;
    }
}

Android has a method of chaining views together in its constraint based layout system that I wanted to mimic. Searches brought me here but none of the answers quite worked. I didn't want to use StackViews because they tend to cause me more grief down the line than they save up front. I ended up creating a solution that used UILayoutGuides placed between the views. Controlling their width's allows different types of distributions, chain styles in Android parlance. The function accepts a leading and trailing anchor instead of a parent view. This allows the chain to be placed between two arbitrary views rather than distributed inside of the parent view. It does use UILayoutGuide which is only available in iOS 9+ but that shouldn't be a problem anymore.

public enum LayoutConstraintChainStyle {
    case spread //Evenly distribute between the anchors
    case spreadInside //Pin the first & last views to the sides and then evenly distribute
    case packed //The views have a set space but are centered between the anchors.
}

public extension NSLayoutConstraint {

    static func chainHorizontally(views: [UIView],
                                  leadingAnchor: NSLayoutXAxisAnchor,
                                  trailingAnchor: NSLayoutXAxisAnchor,
                                  spacing: CGFloat = 0.0,
                                  style: LayoutConstraintChainStyle = .spread) -> [NSLayoutConstraint] {
    var constraints = [NSLayoutConstraint]()
    guard views.count > 1 else { return constraints }
    guard let first = views.first, let last = views.last, let superview = first.superview else { return constraints }

    //Setup the chain of views
    var distributionGuides = [UILayoutGuide]()
    var previous = first
    let firstGuide = UILayoutGuide()
    superview.addLayoutGuide(firstGuide)
    distributionGuides.append(firstGuide)
    firstGuide.identifier = "ChainDistribution\(distributionGuides.count)"
    constraints.append(firstGuide.leadingAnchor.constraint(equalTo: leadingAnchor))
    constraints.append(first.leadingAnchor.constraint(equalTo: firstGuide.trailingAnchor, constant: spacing))
    views.dropFirst().forEach { view in
        let g = UILayoutGuide()
        superview.addLayoutGuide(g)
        distributionGuides.append(g)
        g.identifier = "ChainDistribution\(distributionGuides.count)"
        constraints.append(contentsOf: [
            g.leadingAnchor.constraint(equalTo: previous.trailingAnchor),
            view.leadingAnchor.constraint(equalTo: g.trailingAnchor)
        ])
        previous = view
    }
    let lastGuide = UILayoutGuide()
    superview.addLayoutGuide(lastGuide)
    constraints.append(contentsOf: [lastGuide.leadingAnchor.constraint(equalTo: last.trailingAnchor),
                                    lastGuide.trailingAnchor.constraint(equalTo: trailingAnchor)])
    distributionGuides.append(lastGuide)

    //Space the according to the style.
    switch style {
    case .packed:
        if let first = distributionGuides.first, let last = distributionGuides.last {
            constraints.append(first.widthAnchor.constraint(greaterThanOrEqualToConstant: spacing))
            constraints.append(last.widthAnchor.constraint(greaterThanOrEqualToConstant: spacing))
            constraints.append(last.widthAnchor.constraint(equalTo: first.widthAnchor))
            constraints.append(contentsOf:
                distributionGuides.dropFirst().dropLast()
                    .map { $0.widthAnchor.constraint(equalToConstant: spacing) }
                )
        }
    case .spread:
        if let first = distributionGuides.first {
            constraints.append(contentsOf:
                distributionGuides.dropFirst().map { $0.widthAnchor.constraint(equalTo: first.widthAnchor) })
        }
    case .spreadInside:
        if let first = distributionGuides.first, let last = distributionGuides.last {
            constraints.append(first.widthAnchor.constraint(equalToConstant: spacing))
            constraints.append(last.widthAnchor.constraint(equalToConstant: spacing))
            let innerGuides = distributionGuides.dropFirst().dropLast()
            if let key = innerGuides.first {
                constraints.append(contentsOf:
                    innerGuides.dropFirst().map { $0.widthAnchor.constraint(equalTo: key.widthAnchor) }
                )
            }
        }
    }

    return constraints
}

查看https://developer.apple.com/library/ios/documentation/UserExperience/Conceptual/AutolayoutPG/AutoLayoutbyExample/AutoLayoutbyExample.html，上面有关于解决问题的详细描述。