Question

我已经启动了IOS Jump Right在快速IOS编程的介绍中，我目前正处于这个阶段：[图像] [1]代码如下：

 button.translatesAutoresizingMaskIntoConstraints = false;
 button.heightAnchor.constraint(equalToConstant: 44.0).isActive = true
 button.widthAnchor.constraint(equalToConstant: 44.0).isActive = true

这会产生以下错误：

    Unable to simultaneously satisfy constraints.
    Probably at least one of the constraints in the following list is one you 
    don't want. 
    Try this: 
        (1) look at each constraint and try to figure out which you don't expect; 
        (2) find the code that added the unwanted constraint or constraints and fix it. 
    NSLayoutConstraint:0x604000091760 UIButton:0x7f7f95519110.width == 44   (active)
    NSLayoutConstraint:0x600000097020 'UISV-canvas-connection' FoodTracker.RatingControl:0x7f7f95412d20.leading == UIButton:0x7f7f95519110.leading   (active),
    NSLayoutConstraint:0x600000093bf0 'UISV-canvas-connection' H:[UIButton:0x7f7f95519110]-(0)-|   (active, names: '|':FoodTracker.RatingControl:0x7f7f95412d20 ),
    NSLayoutConstraint:0x600000099fa0 'UIView-Encapsulated-Layout-Width' FoodTracker.RatingControl:0x7f7f95412d20.width == 200   (active)


Will attempt to recover by breaking constraint 
NSLayoutConstraint:0x604000091760 UIButton:0x7f7f95519110.width == 44   (active)

这是在一个链接到水平堆栈视图的“自定义”类中，我尝试将self.autoresizeSubviews设置为false。设置self.translateAutoresizingMaskIntoConstraints = false会删除错误，但堆栈视图的x，y位置默认为0,0。如果出现约束冲突：

 button.translatesAutoresizingMaskIntoConstraints = false;

删除按钮上的所有约束。

编辑，完整代码：

class RatingControl: UIStackView {

//MARK: init
override init(frame: CGRect) {
    super.init(frame: frame)
    setupButtons()
}

required init(coder: NSCoder) {
    super.init(coder: coder)
    setupButtons()
}

//MARK: Actions

func ratingButtonTapped(button: UIButton) {
    print("HELLO WORLD!");
}

//MARK: private methods

private func setupButtons() {

    // Create the button
    let button = UIButton()
    button.backgroundColor = UIColor.red

    //self.translatesAutoresizingMaskIntoConstraints = false;




    // Add constraints

    button.translatesAutoresizingMaskIntoConstraints = false;
    button.heightAnchor.constraint(equalToConstant: 44.0).isActive = true
    button.widthAnchor.constraint(equalToConstant: 44.0).isActive = true

    // Add the button to the stack
    addArrangedSubview(button)
}

}

Answer 1

这种错误称为不满意的布局。基本上，对于您定义的约束，系统无法找到符合所有约束条件的有效解决方案。通过你发布的内容，我可以很容易地确定这组约束：

button.height = 44 //以编程方式使用layoutAnchors定义
button.width = 44 //以编程方式定义高度layoutAnchors

然后你还有其他基于Interface builder的约束：

RatingControl.leading = UIButton.leading
带按钮和评级控件的水平堆栈视图我认为
RatingControl.with = 200

要避免此类错误，您需要：

删除一个约束。您认为正在制造冲突的那个

OR - 通过降低优先级使其成为可选项来更改约束

Answer 2

在学习本教程时，我遇到了类似的问题。

我意识到，“实施自定义控件”一章中的水平堆栈视图没有嵌入在“构建更好的UI”一章中先前创建的“垂直堆栈视图”中。看看是否能为您解决问题。

Swift无法满足Jump Right In中的约束

2 个答案:

Swift无法满​​足Jump Right In中的约束

2 个答案:

Swift无法满足Jump Right In中的约束