如何连续运行JavaScript函数？

Question

我正在通过https://javascript30.com挑战5.我已经解决了问题，但我正在尝试“升级”，以便在新面板打开之前所有“打开”面板都会关闭。

无论如何，更具体地说，在这种情况下，当点击一个面板时，我需要运行closeOpens()to。之后，我需要点击面板继续打开等。

const PANELS = document.querySelectorAll('.panel');
/**
  * Look for open panels and close them.
*/
function closeOpens() {
  let opens = document.querySelectorAll('.open');
  console.log('hi'); // TODO: Doesn't display!

  // Close any 'open' panels first!
  if (opens.length > 0) {
    opens.forEach((o) => {
      o.classList.remove('open');
    });
  }
}

PANELS.forEach((panel) => {
  panel.addEventListener('click', closeOpens => {
  panel.classList.add('open');

  });

  panel.addEventListener('transitionend', e => {
    if (e.propertyName.includes('flex')) {
      e.target.classList.toggle('v-slide-in');
    }
  });
});

如上所述，console.log('hi');没有运行。 'click'事件刚刚进入...add('open)'

为了完整性，这里是标记和样式的其余部分，但这实际上只是一个JS问题：

<style>
    html {
      box-sizing: border-box;
      background: #ffc600;
      font-family: 'helvetica neue';
      font-size: 20px;
      font-weight: 200;
    }

    body {
      margin: 0;
    }

    *,
    *: before,
    *: after {
      box-sizing: inherit;
    }

    .panels {
      min-height: 100vh;
      overflow: hidden;

      display: flex;
    }

    .panel {
      background: #6B0F9C;
      box-shadow: inset 0 0 0 5px rgba(255, 255, 255, 0.1);
      color: white;
      text-align: center;
      align-items: center;
      /* Safari transitionend event.propertyName === flex */
      /* Chrome + FF transitionend event.propertyName === flex-grow */
      transition: font-size 0.7s cubic-bezier(0.61, -0.19, 0.7, -0.11),
      flex 0.7s cubic-bezier(0.61, -0.19, 0.7, -0.11),
      background 0.2s;
      font-size: 20px;
      background-size: cover;
      background-position: center;
      flex: 1;
      /* Split space amongst children */
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .panel1 {
      background-image: url(https://source.unsplash.com/gYl-UtwNg_I/1500x1500);
    }

    .panel2 {
      background-image: url(https://source.unsplash.com/rFKUFzjPYiQ/1500x1500);
    }

    .panel3 {
      background-image: url(https://images.unsplash.com/photo-1465188162913-8fb5709d6d57?ixlib=rb-0.3.5&q=80&fm=jpg&crop=faces&cs=tinysrgb&w=1500&h=1500&fit=crop&s=967e8a713a4e395260793fc8c802901d);
    }

    .panel4 {
      background-image: url(https://source.unsplash.com/ITjiVXcwVng/1500x1500);
    }

    .panel5 {
      background-image: url(https://source.unsplash.com/3MNzGlQM7qs/1500x1500);
    }

    .panel>* {
      margin: 0;
      width: 100%;
      transition: transform 0.5s;

      flex: 1 0 auto;
      display: flex;
      justify-content: center;
      align-items: center;
    }

    .panel>*:first-child {
      transform: translateY(-100%);
    }

    .panel.v-slide-in>*:first-child,
    .panel.v-slide-in>*:last-child {
      transform: translateY(0);
    }

    .panel>*:last-child {
      transform: translateY(100%);
    }

    .panel p {
      text-transform: uppercase;
      font-family: 'Amatic SC', cursive;
      text-shadow: 0 0 4px rgba(0, 0, 0, 0.72), 0 0 14px rgba(0, 0, 0, 0.45);
      font-size: 2em;
    }

    .panel p: nth-child(2) {
      font-size: 4em;
    }

    .panel.open {
      font-size: 40px;
      flex: 5;
    }
  </style>

  <div class="panels">
    <div class="panel panel1">
      <p>Hey</p>
      <p>Let's</p>
      <p>Dance</p>
    </div>
    <div class="panel panel2">
      <p>Give</p>
      <p>Take</p>
      <p>Receive</p>
    </div>
    <div class="panel panel3">
      <p>Experience</p>
      <p>It</p>
      <p>Today</p>
    </div>
    <div class="panel panel4">
      <p>Give</p>
      <p>All</p>
      <p>You can</p>
    </div>
    <div class="panel panel5">
      <p>Life</p>
      <p>In</p>
      <p>Motion</p>
    </div>
  </div>

Answer 1

只需在click处理程序中调用closeOpens()。它将关闭现有的打开面板，然后打开单击的面板。

panel.addEventListener('click', () => {
  closeOpens();
  panel.classList.add('open');
});

const PANELS = document.querySelectorAll('.panel');
/**
  * Look for open panels and close them.
*/
function closeOpens() {
  let opens = document.querySelectorAll('.open');
  console.log('hi'); // TODO: Doesn't display!

  // Close any 'open' panels first!
  if (opens.length > 0) {
    opens.forEach((o) => {
      o.classList.remove('open');
    });
  }
}

PANELS.forEach((panel) => {
  panel.addEventListener('click', () => {
  closeOpens();
  panel.classList.add('open');

  });

  panel.addEventListener('transitionend', e => {
    if (e.propertyName.includes('flex')) {
      e.target.classList.toggle('v-slide-in');
    }
  });
});

html {
      box-sizing: border-box;
      background: #ffc600;
      font-family: 'helvetica neue';
      font-size: 20px;
      font-weight: 200;
    }

    body {
      margin: 0;
    }

    *,
    *: before,
    *: after {
      box-sizing: inherit;
    }

    .panels {
      min-height: 100vh;
      overflow: hidden;

      display: flex;
    }

    .panel {
      background: #6B0F9C;
      box-shadow: inset 0 0 0 5px rgba(255, 255, 255, 0.1);
      color: white;
      text-align: center;
      align-items: center;
      /* Safari transitionend event.propertyName === flex */
      /* Chrome + FF transitionend event.propertyName === flex-grow */
      transition: font-size 0.7s cubic-bezier(0.61, -0.19, 0.7, -0.11),
      flex 0.7s cubic-bezier(0.61, -0.19, 0.7, -0.11),
      background 0.2s;
      font-size: 20px;
      background-size: cover;
      background-position: center;
      flex: 1;
      /* Split space amongst children */
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .panel1 {
      background-image: url(https://source.unsplash.com/gYl-UtwNg_I/1500x1500);
    }

    .panel2 {
      background-image: url(https://source.unsplash.com/rFKUFzjPYiQ/1500x1500);
    }

    .panel3 {
      background-image: url(https://images.unsplash.com/photo-1465188162913-8fb5709d6d57?ixlib=rb-0.3.5&q=80&fm=jpg&crop=faces&cs=tinysrgb&w=1500&h=1500&fit=crop&s=967e8a713a4e395260793fc8c802901d);
    }

    .panel4 {
      background-image: url(https://source.unsplash.com/ITjiVXcwVng/1500x1500);
    }

    .panel5 {
      background-image: url(https://source.unsplash.com/3MNzGlQM7qs/1500x1500);
    }

    .panel>* {
      margin: 0;
      width: 100%;
      transition: transform 0.5s;

      flex: 1 0 auto;
      display: flex;
      justify-content: center;
      align-items: center;
    }

    .panel>*:first-child {
      transform: translateY(-100%);
    }

    .panel.v-slide-in>*:first-child,
    .panel.v-slide-in>*:last-child {
      transform: translateY(0);
    }

    .panel>*:last-child {
      transform: translateY(100%);
    }

    .panel p {
      text-transform: uppercase;
      font-family: 'Amatic SC', cursive;
      text-shadow: 0 0 4px rgba(0, 0, 0, 0.72), 0 0 14px rgba(0, 0, 0, 0.45);
      font-size: 2em;
    }

    .panel p: nth-child(2) {
      font-size: 4em;
    }

    .panel.open {
      font-size: 40px;
      flex: 5;
    }

<div class="panels">
  <div class="panel panel1">
    <p>Hey</p>
    <p>Let's</p>
    <p>Dance</p>
  </div>
  <div class="panel panel2">
    <p>Give</p>
    <p>Take</p>
    <p>Receive</p>
  </div>
  <div class="panel panel3">
    <p>Experience</p>
    <p>It</p>
    <p>Today</p>
  </div>
  <div class="panel panel4">
    <p>Give</p>
    <p>All</p>
    <p>You can</p>
  </div>
  <div class="panel panel5">
    <p>Life</p>
    <p>In</p>
    <p>Motion</p>
  </div>
</div>

Answer 2

听起来你有两个功能要做：关闭所有面板，然后打开一个面板。从您需要执行的两个任务开始，不要担心事件。

function closePanels(){
    //do work
}

function openPanel(el){
    //do work
}

现在您已经能够执行需要执行的操作，您可以在逻辑多步骤任务中连接它们。

PANELS.forEach((panel) => {
  panel.addEventListener('click', function(){
        closePanels();
        openPanel(this);
  });
});

通过这种方式，我们将各个工作单元与特定的复杂任务分开。