Javascript - 在跨度范围之上添加一个新的 DIV

Question

I have the following code on codesandbox: https://codesandbox.io/s/highlighter-cv2kv?file=/src/index.js

I have a bunch of spans for every word in a phrase. I want to be able to create highlights based on a start and end time (every span has those details in dataset). Highlights need to be laid above the corresponding spans.

So far I've been able to highlight the start and stop word but I need to highlight every word between that interval.

Current state:

Desired state:

Any ideas on how can I do this in the most efficient way?

Answer 1

i have an i idea for you less js more css, with that you only need to toggle the class playing and will highlight the words:

    body {
  font-family: sans-serif;
}

.will-play {
  position: inherit;
  z-index: 1;
  position: relative;
}
.will-play.playing::after {
  z-index: 200;
  position: absolute;
  top: 0;
  left: 0;

  height: 100%;
  width: 100%;
  background-color: yellow;
  opacity: 0.5;
  content: "";
}

I forgot the JS:

let ranges = { start: "80.9", end: "87.48" };


let spans = [...document.querySelectorAll("span.will-play")];

spans.map((item) => {
  if(item.dataset.start>=ranges.start && item.dataset.end<=ranges.end){
    item.classList.add('playing')
  }
});

Answer 2

Using dataset and querySelectorAll

Working Demo

for (let range of ranges) {
  parent.querySelectorAll('.will-play').forEach (span => {
    if (span.dataset.start < range.start || span.dataset.end > range.end) {
      return;
    }

    let highLightParent = document.createElement("div");    
    let highlight = document.createElement("div");
    let pos = getPos(parent, span);
    highlight.style.cssText = `position: absolute; top: ${pos.top}px; left: ${pos.left}px; width: ${span.offsetWidth}px; height: ${span.offsetHeight}px; background-color: yellow; opacity: 0.5; z-index: 1`;

    highLightParent.appendChild(highlight);    
    parent.appendChild(highLightParent);
  });
}