自动布局让我的生活很困难。从理论上讲,当我转换的时候,它会非常有用,但我似乎一直在与它作斗争。

我做了一个演示项目来寻求帮助。有人知道如何使视图之间的空间增加或减少均匀,每当视图调整大小?

下面是三个标签(手动垂直对齐):

我想要的是,当我旋转时,它们均匀地调整间距(而不是视图大小)。默认情况下,顶部和底部视图向中心挤压:


当前回答

这里还有另一个答案。我在回答一个类似的问题时看到了这个问题的链接。我没有看到任何与我类似的答案。所以我想写在这里。

  class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = UIColor.whiteColor()
        setupViews()
    }

    var constraints: [NSLayoutConstraint] = []

    func setupViews() {

        let container1 = createButtonContainer(withButtonTitle: "Button 1")
        let container2 = createButtonContainer(withButtonTitle: "Button 2")
        let container3 = createButtonContainer(withButtonTitle: "Button 3")
        let container4 = createButtonContainer(withButtonTitle: "Button 4")

        view.addSubview(container1)
        view.addSubview(container2)
        view.addSubview(container3)
        view.addSubview(container4)

        [

            // left right alignment
            container1.leftAnchor.constraintEqualToAnchor(view.leftAnchor, constant: 20),
            container1.rightAnchor.constraintEqualToAnchor(view.rightAnchor, constant: -20),
            container2.leftAnchor.constraintEqualToAnchor(container1.leftAnchor),
            container2.rightAnchor.constraintEqualToAnchor(container1.rightAnchor),
            container3.leftAnchor.constraintEqualToAnchor(container1.leftAnchor),
            container3.rightAnchor.constraintEqualToAnchor(container1.rightAnchor),
            container4.leftAnchor.constraintEqualToAnchor(container1.leftAnchor),
            container4.rightAnchor.constraintEqualToAnchor(container1.rightAnchor),


            // place containers one after another vertically
            container1.topAnchor.constraintEqualToAnchor(view.topAnchor),
            container2.topAnchor.constraintEqualToAnchor(container1.bottomAnchor),
            container3.topAnchor.constraintEqualToAnchor(container2.bottomAnchor),
            container4.topAnchor.constraintEqualToAnchor(container3.bottomAnchor),
            container4.bottomAnchor.constraintEqualToAnchor(view.bottomAnchor),


            // container height constraints
            container2.heightAnchor.constraintEqualToAnchor(container1.heightAnchor),
            container3.heightAnchor.constraintEqualToAnchor(container1.heightAnchor),
            container4.heightAnchor.constraintEqualToAnchor(container1.heightAnchor)
            ]
            .forEach { $0.active = true }
    }


    func createButtonContainer(withButtonTitle title: String) -> UIView {
        let view = UIView(frame: .zero)
        view.translatesAutoresizingMaskIntoConstraints = false

        let button = UIButton(type: .System)
        button.translatesAutoresizingMaskIntoConstraints = false
        button.setTitle(title, forState: .Normal)
        view.addSubview(button)

        [button.centerYAnchor.constraintEqualToAnchor(view.centerYAnchor),
            button.leftAnchor.constraintEqualToAnchor(view.leftAnchor),
            button.rightAnchor.constraintEqualToAnchor(view.rightAnchor)].forEach { $0.active = true }

        return view
    }
}

同样,这也可以用iOS9 UIStackViews很容易做到。

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = UIColor.greenColor()
        setupViews()
    }

    var constraints: [NSLayoutConstraint] = []

    func setupViews() {

        let container1 = createButtonContainer(withButtonTitle: "Button 1")
        let container2 = createButtonContainer(withButtonTitle: "Button 2")
        let container3 = createButtonContainer(withButtonTitle: "Button 3")
        let container4 = createButtonContainer(withButtonTitle: "Button 4")

        let stackView = UIStackView(arrangedSubviews: [container1, container2, container3, container4])
        stackView.translatesAutoresizingMaskIntoConstraints = false
        stackView.axis = .Vertical
        stackView.distribution = .FillEqually
        view.addSubview(stackView)

        [stackView.topAnchor.constraintEqualToAnchor(view.topAnchor),
            stackView.bottomAnchor.constraintEqualToAnchor(view.bottomAnchor),
            stackView.leftAnchor.constraintEqualToAnchor(view.leftAnchor, constant: 20),
            stackView.rightAnchor.constraintEqualToAnchor(view.rightAnchor, constant: -20)].forEach { $0.active = true }
    }


    func createButtonContainer(withButtonTitle title: String) -> UIView {
        let button = UIButton(type: .Custom)
        button.translatesAutoresizingMaskIntoConstraints = false
        button.backgroundColor = UIColor.redColor()
        button.setTitleColor(UIColor.whiteColor(), forState: .Normal)
        button.setTitle(title, forState: .Normal)
        let buttonContainer = UIStackView(arrangedSubviews: [button])
        buttonContainer.distribution = .EqualCentering
        buttonContainer.alignment = .Center
        buttonContainer.translatesAutoresizingMaskIntoConstraints = false
        return buttonContainer
    }
}

注意,这与上面的方法完全相同。它添加了四个容器视图,这些视图都是均等填充的,每个堆栈视图都添加了一个视图,并在中间对齐。但是,这个版本的UIStackView减少了一些代码,看起来不错。

其他回答

基于Ben Dolman的回答,这将更均匀地分配视图(使用填充等):

+(NSArray *)constraintsForEvenDistributionOfItems:(NSArray *)views
                           relativeToCenterOfItem:(id)toView vertically:(BOOL)vertically
{
    NSMutableArray *constraints = [NSMutableArray new];
    NSLayoutAttribute attr = vertically ? NSLayoutAttributeCenterY : NSLayoutAttributeCenterX;

    CGFloat min = 0.25;
    CGFloat max = 1.75;
    CGFloat d = (max-min) / ([views count] - 1);
    for (NSUInteger i = 0; i < [views count]; i++) {
        id view = views[i];
        CGFloat multiplier = i * d + min;
        NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:view
                                                                      attribute:attr
                                                                      relatedBy:NSLayoutRelationEqual
                                                                         toItem:toView
                                                                      attribute:attr
                                                                     multiplier:multiplier
                                                                       constant:0];
        [constraints addObject:constraint];
    }

    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。

在InterfaceBuilder中解决这个问题非常简单:

设置居中标签(label2)为“水平容器中心”和“垂直容器中心”

选择居中标签和顶部标签(label1 + label2),并为垂直间距添加两个约束。大于或等于最小间距的一个。小于或等于最大间距的一个。

中间的标签和底部的标签(label2 + label3)也是如此。

此外,您还可以添加两个约束label1 -顶部空间到SuperView和两个约束label2 -底部空间到SuperView。

结果是所有4个空格的大小变化相同。

这里还有另一个答案。我在回答一个类似的问题时看到了这个问题的链接。我没有看到任何与我类似的答案。所以我想写在这里。

  class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = UIColor.whiteColor()
        setupViews()
    }

    var constraints: [NSLayoutConstraint] = []

    func setupViews() {

        let container1 = createButtonContainer(withButtonTitle: "Button 1")
        let container2 = createButtonContainer(withButtonTitle: "Button 2")
        let container3 = createButtonContainer(withButtonTitle: "Button 3")
        let container4 = createButtonContainer(withButtonTitle: "Button 4")

        view.addSubview(container1)
        view.addSubview(container2)
        view.addSubview(container3)
        view.addSubview(container4)

        [

            // left right alignment
            container1.leftAnchor.constraintEqualToAnchor(view.leftAnchor, constant: 20),
            container1.rightAnchor.constraintEqualToAnchor(view.rightAnchor, constant: -20),
            container2.leftAnchor.constraintEqualToAnchor(container1.leftAnchor),
            container2.rightAnchor.constraintEqualToAnchor(container1.rightAnchor),
            container3.leftAnchor.constraintEqualToAnchor(container1.leftAnchor),
            container3.rightAnchor.constraintEqualToAnchor(container1.rightAnchor),
            container4.leftAnchor.constraintEqualToAnchor(container1.leftAnchor),
            container4.rightAnchor.constraintEqualToAnchor(container1.rightAnchor),


            // place containers one after another vertically
            container1.topAnchor.constraintEqualToAnchor(view.topAnchor),
            container2.topAnchor.constraintEqualToAnchor(container1.bottomAnchor),
            container3.topAnchor.constraintEqualToAnchor(container2.bottomAnchor),
            container4.topAnchor.constraintEqualToAnchor(container3.bottomAnchor),
            container4.bottomAnchor.constraintEqualToAnchor(view.bottomAnchor),


            // container height constraints
            container2.heightAnchor.constraintEqualToAnchor(container1.heightAnchor),
            container3.heightAnchor.constraintEqualToAnchor(container1.heightAnchor),
            container4.heightAnchor.constraintEqualToAnchor(container1.heightAnchor)
            ]
            .forEach { $0.active = true }
    }


    func createButtonContainer(withButtonTitle title: String) -> UIView {
        let view = UIView(frame: .zero)
        view.translatesAutoresizingMaskIntoConstraints = false

        let button = UIButton(type: .System)
        button.translatesAutoresizingMaskIntoConstraints = false
        button.setTitle(title, forState: .Normal)
        view.addSubview(button)

        [button.centerYAnchor.constraintEqualToAnchor(view.centerYAnchor),
            button.leftAnchor.constraintEqualToAnchor(view.leftAnchor),
            button.rightAnchor.constraintEqualToAnchor(view.rightAnchor)].forEach { $0.active = true }

        return view
    }
}

同样,这也可以用iOS9 UIStackViews很容易做到。

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = UIColor.greenColor()
        setupViews()
    }

    var constraints: [NSLayoutConstraint] = []

    func setupViews() {

        let container1 = createButtonContainer(withButtonTitle: "Button 1")
        let container2 = createButtonContainer(withButtonTitle: "Button 2")
        let container3 = createButtonContainer(withButtonTitle: "Button 3")
        let container4 = createButtonContainer(withButtonTitle: "Button 4")

        let stackView = UIStackView(arrangedSubviews: [container1, container2, container3, container4])
        stackView.translatesAutoresizingMaskIntoConstraints = false
        stackView.axis = .Vertical
        stackView.distribution = .FillEqually
        view.addSubview(stackView)

        [stackView.topAnchor.constraintEqualToAnchor(view.topAnchor),
            stackView.bottomAnchor.constraintEqualToAnchor(view.bottomAnchor),
            stackView.leftAnchor.constraintEqualToAnchor(view.leftAnchor, constant: 20),
            stackView.rightAnchor.constraintEqualToAnchor(view.rightAnchor, constant: -20)].forEach { $0.active = true }
    }


    func createButtonContainer(withButtonTitle title: String) -> UIView {
        let button = UIButton(type: .Custom)
        button.translatesAutoresizingMaskIntoConstraints = false
        button.backgroundColor = UIColor.redColor()
        button.setTitleColor(UIColor.whiteColor(), forState: .Normal)
        button.setTitle(title, forState: .Normal)
        let buttonContainer = UIStackView(arrangedSubviews: [button])
        buttonContainer.distribution = .EqualCentering
        buttonContainer.alignment = .Center
        buttonContainer.translatesAutoresizingMaskIntoConstraints = false
        return buttonContainer
    }
}

注意,这与上面的方法完全相同。它添加了四个容器视图,这些视图都是均等填充的,每个堆栈视图都添加了一个视图,并在中间对齐。但是,这个版本的UIStackView减少了一些代码,看起来不错。

非常快速的接口构建器解决方案:

对于在一个父视图中均匀间隔的任意数量的视图,简单地给每个水平布局的“对齐中心X到父视图”约束,或垂直布局的“对齐中心Y父视图”,并设置乘数为N:p(注意:有些人有更好的运气p:N -见下文)

在哪里

N =总视图数,和

P =包含空格的视图的位置

第一个位置是1,然后是一个空格,使得下一个位置是3,所以p变成了一个序列[1,3,5,7,9,…]。适用于任何数量的视图。

如果你有3个视图来分隔,它看起来是这样的:

编辑注意:N:p或p:N的选择取决于对齐约束的关系顺序。如果“第一项”是Superview。中心,你可以使用p:N,而如果Superview。中心是“第二项”,你可以用N:p。如果有疑问,可以两种都试一试。: -)