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

许多答案是不正确的,但得到许多计数。这里我只是编写了一个解决方案,三个视图是水平对齐的,不使用间隔视图,但它只在标签宽度已知的情况下工作,当在故事板中使用。

NSDictionary *views = NSDictionaryOfVariableBindings(_redView, _yellowView, _blueView);

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"|->=0-[_redView(40)]->=0-[_yellowView(40)]->=0-[_blueView(40)]->=0-|" options:NSLayoutFormatAlignAllTop | NSLayoutFormatAlignAllBottom metrics:nil views:views]];

[self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[_redView(60)]" options:0 metrics:nil views:views]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:self.view attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:_redView attribute:NSLayoutAttributeCenterY multiplier:1 constant:0]];

[self.view addConstraint:[NSLayoutConstraint constraintWithItem:self.view attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:_yellowView attribute:NSLayoutAttributeCenterX multiplier:1 constant:0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_redView attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:_yellowView attribute:NSLayoutAttributeLeading multiplier:0.5 constant:0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:_blueView attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:_yellowView attribute:NSLayoutAttributeLeading multiplier:1.5 constant:40]];

其他回答

我可以在IB中完全解决这个问题:

使约束使每个子视图的中心Y对齐到父视图的下边缘。 将每个约束的乘数设置为1/2n, 3/2n, 5/2n,…,n-1/2n,其中n是要分布的子视图的数量。

因此,如果您有三个标签,请将每个约束的乘数设置为0.1666667、0.5、0.833333。

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。

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。

我的方法允许你在接口构建器中做这个。你要做的是创建“间隔视图”,你已经设置为匹配高度相等。然后在标签上添加顶部和底部约束(见截图)。

更具体地说,我在“Spacer View 1”上有一个顶部约束,以优先级低于1000的高度约束来superview,并且高度等于所有其他的“Spacer views”。'Spacer View 4'有一个用于superview的底部空间约束。每个标签都有各自的顶部和底部约束到其最近的“间隔视图”。

注意:确保你的标签上没有额外的顶部/底部空间限制;只有那些“空间视图”。这是可以满足的,因为顶部和底部的约束分别在'Space View 1'和'Spacer View 4'上。

废话1:我复制了我的视图,只是把它设置为横向模式,这样你就可以看到它工作了。

废话2:“间隔视图”本可以是透明的。

废话3:这种方法可以横向应用。