AutoLayout - 无法同时满足 swift5 中的约束条件

Question

我的问题发生在您按下 Web 视图侧边栏上的按钮时。该按钮向网络视图发送一条简单消息并复制剪贴板。 Swift 向您显示收到的消息作为敬酒。很简单。

功能似乎没有问题，

但是 UI 是个问题。当按下按钮时，屏幕从上到下滑动，显示吐司，再次按下按钮激活按下侧边栏其他按钮的功能。

画面是一样的，不过画面好像是down了。侧边栏屏幕包含一个滚动条。是这个意思吗？

错误日志：

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. 
    (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSAutoresizingMaskLayoutConstraint:0x283a866c0 h=-&- v=-&- _UIToolbarContentView:0x133ebf3b0.width == UIToolbar:0x133ebef70.width   (active)>",
    "<NSLayoutConstraint:0x283a8b390 H:|-(0)-[_UIButtonBarStackView:0x133ec0570]   (active, names: '|':_UIToolbarContentView:0x133ebf3b0 )>",
    "<NSLayoutConstraint:0x283a8b3e0 _UIButtonBarStackView:0x133ec0570.trailing == _UIToolbarContentView:0x133ebf3b0.trailing   (active)>",
    "<NSLayoutConstraint:0x283a84910 H:|-(16)-[_UIModernBarButton:0x133dcc420]   (active, names: '|':_UIButtonBarButton:0x133dcc1d0 )>",
    "<NSLayoutConstraint:0x283a84960 H:[_UIModernBarButton:0x133dcc420]-(>=8)-|   (active, names: '|':_UIButtonBarButton:0x133dcc1d0 )>",
    "<NSLayoutConstraint:0x283a84f50 H:|-(>=5)-[_UIModernBarButton:0x133ecbe60]   (active, names: '|':_UIButtonBarButton:0x133ecbc10 )>",
    "<NSLayoutConstraint:0x283a84fa0 H:[_UIModernBarButton:0x133ecbe60]-(>=5)-|   (active, names: '|':_UIButtonBarButton:0x133ecbc10 )>",
    "<NSLayoutConstraint:0x283a856d0 H:|-(8)-[_UIModernBarButton:0x133dcd540'Done']   (active, names: '|':_UIButtonBarButton:0x133ecc380 )>",
    "<NSLayoutConstraint:0x283a85720 H:[_UIModernBarButton:0x133dcd540'Done']-(16)-|   (active, names: '|':_UIButtonBarButton:0x133ecc380 )>",
    "<NSLayoutConstraint:0x283a85ae0 'UISV-canvas-connection' UILayoutGuide:0x2820c1c00'UIViewLayoutMarginsGuide'.leading == _UIButtonBarButton:0x133dcc1d0.leading   (active)>",
    "<NSLayoutConstraint:0x283a85cc0 'UISV-canvas-connection' UILayoutGuide:0x2820c1c00'UIViewLayoutMarginsGuide'.trailing == _UIButtonBarButton:0x133ecc380.trailing   (active)>",
    "<NSLayoutConstraint:0x283a85d10 'UISV-spacing' H:[_UIButtonBarButton:0x133dcc1d0]-(0)-[UIView:0x133e94d90]   (active)>",
    "<NSLayoutConstraint:0x283a85d60 'UISV-spacing' H:[UIView:0x133e94d90]-(0)-[_UIButtonBarButton:0x133ecbc10]   (active)>",
    "<NSLayoutConstraint:0x283a85db0 'UISV-spacing' H:[_UIButtonBarButton:0x133ecbc10]-(0)-[UIView:0x133ecc1a0]   (active)>",
    "<NSLayoutConstraint:0x283a85e00 'UISV-spacing' H:[UIView:0x133ecc1a0]-(0)-[_UIButtonBarButton:0x133ecc380]   (active)>",
    "<NSLayoutConstraint:0x283a835c0 'UIView-Encapsulated-Layout-Width' UIToolbar:0x133ebef70.width == 0   (active)>",
    "<NSLayoutConstraint:0x283a8b250 'UIView-leftMargin-guide-constraint' H:|-(0)-[UILayoutGuide:0x2820c1c00'UIViewLayoutMarginsGuide'](LTR)   (active, names: '|':_UIButtonBarStackView:0x133ec0570 )>",
    "<NSLayoutConstraint:0x283a8b2f0 'UIView-rightMargin-guide-constraint' H:[UILayoutGuide:0x2820c1c00'UIViewLayoutMarginsGuide']-(0)-|(LTR)   (active, names: '|':_UIButtonBarStackView:0x133ec0570 )>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x283a84960 H:[_UIModernBarButton:0x133dcc420]-(>=8)-|   (active, names: '|':_UIButtonBarButton:0x133dcc1d0 )>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKitCore/UIView.h> may also be helpful.

我很想解决这个问题

编辑

找到问题原因。按下按钮将调出键盘并再次消失。为什么会这样？

这个按钮的作用是和我交流。按钮让我给他看祝酒辞。

JS函数

function copy_address(){
      var t = document.createElement("textarea");
      document.body.appendChild(t);
      t.value = $("#text").val();
      t.select();
      document.execCommand('copy');
      document.body.removeChild(t);
      var postData = {
                tip: "testing",
                message: "sucess",
                timestamp: (new Date()).getTime().toString()
        };
        webkit.messageHandlers.send.postMessage(postData);
}

JSP 按钮视图

<div class="w" id="user"></div>
<div class="b-copy">
    <button type="button" class="btn" onclick="copy_address()">copy</button>
    <input type="text" id="copy_text" style="display: none;">
</div>

Swift WebViewController 中的代码

import Toaster
...
    override func loadView() {
        super.loadView()
      ...
        mainWebView = WKWebView(frame: mainWebView.frame, configuration: config)

        mainWebView.uiDelegate = self
        mainWebView.navigationDelegate = self

        view.addSubview(mainWebView)
        view.addSubview(indicatorImage)
}
    @available(iOS 8.0, *)
    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
        if message.name == "message" {
            let sendmessage = message.body as! NSDictionary
            guard sendmessage["val"] != nil else {
                return
            }
            let val : String = sendmessage["val"] as! String
            if sendmessage["val2"] != nil {
                getmessage = sendmessage["val2"] as? String
            }
          switch val {
            case "testing":
                Toast(text: getmessage).show()
                break
        ....
}
}

Answer 1

我通过模拟器发现了这个问题

当我检查我的实际 iPhone 时，屏幕看起来像是从上到下下降，因为我看不到键盘，但实际上是短暂的看一下然后就消失了。

这就是工具栏高度出现问题的原因。而键盘出问题的原因是JS函数。

t.select(); 
document.execCommand('copy');

由于这部分，键盘可见并消失了。所以我通过搜索解决了这个问题。

t.readOnly = true;

我已经通过添加这段代码解决了我的问题。

AutoLayout - 无法同时满足 swift5 中的约束条件

AutoLayout - Unable to simultaneously satisfy constraints in swift5

storyboard

ios

swift

编辑

找到问题原因。按下按钮将调出键盘并再次消失。为什么会这样？