是的，你可以只在接口构建器中这样做，而不需要编写代码——需要注意的是，你是在调整标签的大小，而不是分配空白。在本例中，将标签2的X和Y对齐到父视图，使其固定在中心。然后将标签1的垂直空间设置为superview，标签2设置为standard，重复标签3。在设置标签2之后，设置标签1和3最简单的方法是调整它们的大小，直到它们断开。

这是水平显示，注意标签1和2之间的垂直空间被设置为标准:

这是竖屏版本:

我意识到，由于标签之间的标准空间和父视图的标准空间之间的差异，它们在基线之间不是绝对100%等间距的。如果这让您感到困扰，可以将大小设置为0而不是standard

我做了一个函数可能会有帮助。 用法示例:

 [self.view addConstraints: [NSLayoutConstraint fluidConstraintWithItems:NSDictionaryOfVariableBindings(button1, button2, button3)
                                                                asString:@[@"button1", @"button2", @"button3"]
                                                               alignAxis:@"V"
                                                          verticalMargin:100
                                                        horizontalMargin:50
                                                             innerMargin:25]];

会导致垂直分布(不好意思没有10个声望来嵌入图像)。如果你改变坐标轴和一些边距值

alignAxis:@"H"
verticalMargin:120
horizontalMargin:20
innerMargin:10

你会得到水平分布。

我是iOS的新手，但是voilà !

EvenDistribution.h

@interface NSLayoutConstraint (EvenDistribution)

/**
 * Returns constraints that will cause a set of subviews
 * to be evenly distributed along an axis.
 */
+ (NSArray *)  fluidConstraintWithItems:(NSDictionary *) views
                               asString:(NSArray *) stringViews
                              alignAxis:(NSString *) axis
                         verticalMargin:(NSUInteger) vMargin
                       horizontalMargin:(NSUInteger) hMargin
                            innerMargin:(NSUInteger) inner;
@end

EvenDistribution.m

#import "EvenDistribution.h"

@implementation NSLayoutConstraint (EvenDistribution)

+ (NSArray *) fluidConstraintWithItems:(NSDictionary *) dictViews
                              asString:(NSArray *) stringViews
                             alignAxis:(NSString *) axis
                        verticalMargin:(NSUInteger) vMargin
                      horizontalMargin:(NSUInteger) hMargin
                           innerMargin:(NSUInteger) iMargin

{
    NSMutableArray *constraints = [NSMutableArray arrayWithCapacity: dictViews.count];
    NSMutableString *globalFormat = [NSMutableString stringWithFormat:@"%@:|-%d-",
                                     axis,
                                     [axis isEqualToString:@"V"] ? vMargin : hMargin
                                     ];



        for (NSUInteger i = 0; i < dictViews.count; i++) {

            if (i == 0)
                [globalFormat appendString:[NSString stringWithFormat: @"[%@]-%d-", stringViews[i], iMargin]];
            else if(i == dictViews.count - 1)
                [globalFormat appendString:[NSString stringWithFormat: @"[%@(==%@)]-", stringViews[i], stringViews[i-1]]];
            else
               [globalFormat appendString:[NSString stringWithFormat: @"[%@(==%@)]-%d-", stringViews[i], stringViews[i-1], iMargin]];

            NSString *localFormat = [NSString stringWithFormat: @"%@:|-%d-[%@]-%d-|",
                                     [axis isEqualToString:@"V"] ? @"H" : @"V",
                                     [axis isEqualToString:@"V"] ? hMargin : vMargin,
                                     stringViews[i],
                                     [axis isEqualToString:@"V"] ? hMargin : vMargin];

            [constraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:localFormat
                                                                                     options:0
                                                                                     metrics:nil
                                                                                       views:dictViews]];


    }
    [globalFormat appendString:[NSString stringWithFormat:@"%d-|",
                                [axis isEqualToString:@"V"] ? vMargin : hMargin
                                ]];

    [constraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:globalFormat
                                                                             options:0
                                                                             metrics:nil
                                                                               views:dictViews]];

    return constraints;

}

@end

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
}

我知道距离第一个答案已经有一段时间了，但我刚刚遇到了同样的问题，我想分享我的解决方案。为了子孙后代……

我在viewDidLoad上设置了视图:

- (void)viewDidLoad {

    [super viewDidLoad];

    cancelButton = [UIButton buttonWithType: UIButtonTypeRoundedRect];
    cancelButton.translatesAutoresizingMaskIntoConstraints = NO;
    [cancelButton setTitle:@"Cancel" forState:UIControlStateNormal];
    [self.view addSubview:cancelButton];

    middleButton = [UIButton buttonWithType: UIButtonTypeRoundedRect];
    middleButton.translatesAutoresizingMaskIntoConstraints = NO;
    [middleButton setTitle:@"Middle" forState:UIControlStateNormal];
    [self.view addSubview:middleButton];

    nextButton = [UIButton buttonWithType: UIButtonTypeRoundedRect];
    nextButton.translatesAutoresizingMaskIntoConstraints = NO;
    [nextButton setTitle:@"Next" forState:UIControlStateNormal];
    [self.view addSubview:nextButton];


    [self.view setNeedsUpdateConstraints];

}

然后，在updateViewConstrains上，首先删除所有约束，然后创建视图字典，然后计算视图之间使用的空间。在那之后，我只是使用视觉语言格式设置约束:

- (void)updateViewConstraints {


    [super updateViewConstraints];

    [self.view removeConstraints:self.view.constraints];

    NSDictionary *viewsDictionary = NSDictionaryOfVariableBindings(cancelButton, nextButton, middleButton);

    float distance=(self.view.bounds.size.width-cancelButton.intrinsicContentSize.width-nextButton.intrinsicContentSize.width-middleButton.intrinsicContentSize.width-20-20)/  ([viewsDictionary count]-1);  // 2 times 20 counts for the left & rigth margins
    NSNumber *distancies=[NSNumber numberWithFloat:distance];

//    NSLog(@"Distancies: %@", distancies);
//    
//    NSLog(@"View Width: %f", self.view.bounds.size.width);
//    NSLog(@"Cancel Width: %f", cancelButton.intrinsicContentSize.width);
//    NSLog(@"Middle Width: %f", middleButton.intrinsicContentSize.width);
//    NSLog(@"Next Width: %f", nextButton.intrinsicContentSize.width);



    NSArray *constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"|-[cancelButton]-dis-[middleButton]-dis-[nextButton]-|"
                                                                   options:NSLayoutFormatAlignAllBaseline
                                                                   metrics:@{@"dis":distancies}
                                                                     views:viewsDictionary];


    [self.view addConstraints:constraints];



    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[nextButton]-|"
                                                          options:0
                                                          metrics:nil
                                                            views:viewsDictionary];
    [self.view addConstraints:constraints];



}

这种方法的好处是你只需要做很少的数学运算。我并不是说这是完美的解决方案，但我为我试图实现的布局工作。

我希望这能有所帮助。

另一种方法可能是让顶部和底部标签分别具有相对于视图顶部和底部的约束，并让中间视图分别具有相对于第一个和第三个视图的顶部和底部约束。

请注意，通过将视图拖到另一个视图附近，直到出现引导虚线，您可以对约束进行更多的控制——这些虚线表示将形成的两个对象之间的约束，而不是对象和父视图之间的约束。

在这种情况下，您可能希望将约束更改为“大于或等于”所需的值，而不是“等于”以允许它们调整大小。不确定这是否能达到你的目的。

查看开源库PureLayout。它提供了一些用于分布视图的API方法，包括每个视图之间的间距是固定的(视图大小根据需要而变化)，以及每个视图的大小是固定的(视图之间的间距根据需要而变化)。请注意，所有这些都是在没有使用任何“间隔视图”的情况下完成的。

从NSArray + PureLayout.h:

// NSArray+PureLayout.h

// ...

/** Distributes the views in this array equally along the selected axis in their superview. Views will be the same size (variable) in the dimension along the axis and will have spacing (fixed) between them. */
- (NSArray *)autoDistributeViewsAlongAxis:(ALAxis)axis
                                alignedTo:(ALAttribute)alignment
                         withFixedSpacing:(CGFloat)spacing;

/** Distributes the views in this array equally along the selected axis in their superview. Views will be the same size (fixed) in the dimension along the axis and will have spacing (variable) between them. */
- (NSArray *)autoDistributeViewsAlongAxis:(ALAxis)axis
                                alignedTo:(ALAttribute)alignment
                            withFixedSize:(CGFloat)size;

// ...

由于它都是开源的，如果您有兴趣了解如何在没有间隔视图的情况下实现这一点，只需查看实现即可。(这取决于同时利用约束的常数和乘数。)