javascript - svg 无法在 IE 中正常显示工具提示，但在 Chrome 中正常显示

Question

我无法在 IE 中正常显示工具提示，但在 Chrome 中正常显示。

1. 使用一些js代码创建名为title的动态标签。

2. 将其添加到 svg 中。

3. Chrome 中的工具提示一切正常，但 IE 中则不然。

<svg id="lang-picker-toggler" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
      <path d="M217.982 201.586h-64.499c-5.537 0-10.026 4.489-10.026 10.026s4.489 10.026 10.026 10.026h53.547c-4.72 25.263-26.935 44.446-53.547 44.446-30.037 0-54.473-24.436-54.473-54.473s24.436-54.473 54.473-54.473c14.55 0 28.229 5.667 38.518 15.955 3.916 3.916 10.264 3.916 14.178 0 3.916-3.916 3.916-10.264 0-14.178-14.077-14.077-32.791-21.829-52.697-21.829-41.094 0-74.525 33.431-74.525 74.525 0 41.094 33.431 74.525 74.525 74.525s74.525-33.431 74.525-74.525c.001-5.536-4.488-10.025-10.025-10.025z"/>
      <path d="M470.331 92.24H269.728l-26.935-81.355a10.025 10.025 0 00-9.518-6.875H41.669C18.693 4.01 0 22.703 0 45.679v332.412c0 22.976 18.693 41.669 41.669 41.669h203.145l27.073 81.369a10.026 10.026 0 009.513 6.861h188.932c22.976 0 41.669-18.693 41.669-41.669V133.909c-.001-22.976-18.694-41.669-41.67-41.669zM41.669 399.708c-11.919 0-21.616-9.697-21.616-21.616V45.679c0-11.919 9.697-21.616 21.616-21.616h184.364l70.691 213.516a.366.366 0 00.015.043l53.664 162.086H41.669zm295.78-116.433c.805 1.11 10.824 14.877 26.355 34.066-4.377 5.756-9.015 11.474-13.91 17.036l-29.712-89.74h87.441c-6.196 13.031-16.938 33.813-31.692 55.736-13.553-16.921-22.069-28.622-22.249-28.87-3.251-4.482-9.519-5.481-14.002-2.23-4.482 3.25-5.48 9.518-2.231 14.002zM265.946 419.76h75.162l-55.503 59.084-19.659-59.084zm226.002 46.561c0 11.919-9.697 21.616-21.616 21.616H304.575l67.015-71.339-.004-.003c.293-.312.571-.64.823-.991a10.025 10.025 0 001.39-9.022l-16.688-50.402c7.073-7.406 13.68-15.143 19.805-22.965 13.299 15.772 29.037 33.446 45.778 50.187 1.957 1.957 4.524 2.937 7.089 2.937s5.132-.979 7.089-2.937c3.916-3.916 3.916-10.264 0-14.178-17.461-17.461-34.013-36.244-47.687-52.632 21.251-30.503 35.033-59.504 40.535-71.954h21.454c5.537 0 10.026-4.489 10.026-10.026s-4.489-10.026-10.026-10.026h-66.173v-18.047c0-5.537-4.489-10.026-10.026-10.026s-10.026 4.489-10.026 10.026v18.046h-51.406l-37.178-112.292H470.33c11.919 0 21.616 9.697 21.616 21.616v332.412z"/>
</svg>

这是我的 JavaScript:

// Create dynamically label for tooltip
var titleEle = document.createElementNS('http://www.w3.org/2000/svg', 'title');
var textString = document.createTextNode(currentLangElement.getAttribute('data-language'));
titleEle.appendChild(textString);
langPickerTogglerElement.appendChild(titleEle);

Answer 1

IE 不会显示 <title> 的任何工具提示根的元素<svg>元素。

svg {border: 1px solid}

<svg>
  <title>IE won't show this as a tooltip</title>
  <rect x="50" y="50" width="50" height="50">
    <title>However this will be in a tooltip even in IE</title>
  </rect>
</svg>

fiddle for IE

Specs明确允许此类行为:

For reasons of accessibility, user agents should always make the content of the ‘title’ child element to the root svg element available to users. However, this is typically done through other means than the tooltips used for nested SVG and graphics elements, e.g., by displaying in a browser tab.

如果您希望工具提示出现在该浏览器中，则必须设置内部元素的 <title>。

就您而言，它可能是 <g>这将包含 <path>元素，如果不是因为其他 IE 奇怪的情况，它们仅当您将鼠标悬停在绘制区域(描边和填充)上时才显示工具提示。
因此，考虑到您的路径没有覆盖整个 svg 元素，希望您的用户将鼠标悬停在正确的位置是有风险的。

因此，这给我们留下了最后一个解决方案，即附加 <rect>它将充当覆盖整个视口(viewport)的不可见背景，并将处理 <title> .

// We are now targetting the <rect> element
var langPickerTogglerElement = document.querySelector('#lang-picker-toggler > rect');
var currentLangElement = document.querySelector('[data-language]');

var titleEle = document.createElementNS('http://www.w3.org/2000/svg', 'title');
var textString = document.createTextNode(currentLangElement.getAttribute('data-language'));
titleEle.appendChild(textString);
langPickerTogglerElement.appendChild(titleEle);

svg {border: 1px solid}

<span data-language="My title text is awesome"></span>
<svg id="lang-picker-toggler" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" width="128" height="128">
  <!-- our tooltip handler, must be a graphic element for IE -->
    <!-- first element so it's set at the background -->
    <!-- cover the whole viewPort -->
    <!-- fill="none" for less work at rendering -->
    <!-- pointer-events=fill so the browser can catch mouse over -->
  <rect
    x="0" y="0" width="512" height="512"
    fill="none"
    pointer-events="fill"/>
  
  <path d="M217.982 201.586h-64.499c-5.537 0-10.026 4.489-10.026 10.026s4.489 10.026 10.026 10.026h53.547c-4.72 25.263-26.935 44.446-53.547 44.446-30.037 0-54.473-24.436-54.473-54.473s24.436-54.473 54.473-54.473c14.55 0 28.229 5.667 38.518 15.955 3.916 3.916 10.264 3.916 14.178 0 3.916-3.916 3.916-10.264 0-14.178-14.077-14.077-32.791-21.829-52.697-21.829-41.094 0-74.525 33.431-74.525 74.525 0 41.094 33.431 74.525 74.525 74.525s74.525-33.431 74.525-74.525c.001-5.536-4.488-10.025-10.025-10.025z"/>
  <path d="M470.331 92.24H269.728l-26.935-81.355a10.025 10.025 0 00-9.518-6.875H41.669C18.693 4.01 0 22.703 0 45.679v332.412c0 22.976 18.693 41.669 41.669 41.669h203.145l27.073 81.369a10.026 10.026 0 009.513 6.861h188.932c22.976 0 41.669-18.693 41.669-41.669V133.909c-.001-22.976-18.694-41.669-41.67-41.669zM41.669 399.708c-11.919 0-21.616-9.697-21.616-21.616V45.679c0-11.919 9.697-21.616 21.616-21.616h184.364l70.691 213.516a.366.366 0 00.015.043l53.664 162.086H41.669zm295.78-116.433c.805 1.11 10.824 14.877 26.355 34.066-4.377 5.756-9.015 11.474-13.91 17.036l-29.712-89.74h87.441c-6.196 13.031-16.938 33.813-31.692 55.736-13.553-16.921-22.069-28.622-22.249-28.87-3.251-4.482-9.519-5.481-14.002-2.23-4.482 3.25-5.48 9.518-2.231 14.002zM265.946 419.76h75.162l-55.503 59.084-19.659-59.084zm226.002 46.561c0 11.919-9.697 21.616-21.616 21.616H304.575l67.015-71.339-.004-.003c.293-.312.571-.64.823-.991a10.025 10.025 0 001.39-9.022l-16.688-50.402c7.073-7.406 13.68-15.143 19.805-22.965 13.299 15.772 29.037 33.446 45.778 50.187 1.957 1.957 4.524 2.937 7.089 2.937s5.132-.979 7.089-2.937c3.916-3.916 3.916-10.264 0-14.178-17.461-17.461-34.013-36.244-47.687-52.632 21.251-30.503 35.033-59.504 40.535-71.954h21.454c5.537 0 10.026-4.489 10.026-10.026s-4.489-10.026-10.026-10.026h-66.173v-18.047c0-5.537-4.489-10.026-10.026-10.026s-10.026 4.489-10.026 10.026v18.046h-51.406l-37.178-112.292H470.33c11.919 0 21.616 9.697 21.616 21.616v332.412z"/>

</svg>

fiddle for IE