AutoLayout - 無法同時滿足 swift5 中的約束

Question

當您按下 web 視圖側邊欄上的按鈕時，會出現我的問題。 該按鈕向 web 視圖發送一條簡單消息並復制剪貼板。 Swift 將收到的消息顯示為敬酒。 這很簡單。

function似乎沒有問題，

但用戶界面是個問題。 按下按鈕時，屏幕從上到下滑動，顯示吐司，再次按下按鈕會激活按下側邊欄上另一個按鈕的 function。

屏幕是一樣的，但屏幕似乎是向下的。 側邊欄屏幕包含一個滾動條。 這就是它的意思嗎？

錯誤日志：

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.

我真的很想解決這個問題。

編輯

---

找到了問題的原因。 按下按鈕將彈出鍵盤並再次消失。 為什么會這樣？

這個按鈕的function和我通訊。 巴頓讓我給他看一條祝酒詞。

JS函數

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 按鈕視圖

<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>

WebViewController 中的 Swift 代碼

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

我通過模擬器發現了這個問題。

當我用我的實際 iPhone 進行檢查時，由於我看不到鍵盤，屏幕看起來像是從上到下往下掉的，但實際上只是看了一小會然后就消失了。

這就是工具欄高度有問題的原因。 鍵盤問題的原因是JS function。

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

由於這部分，鍵盤可見並消失了。 所以我通過搜索解決了這個問題。

t.readOnly = true;

我通過添加此代碼解決了我的問題。