通知下拉放置到按钮

Question

我做了这个概念：https://codepen.io/andrelange91/pen/yLpJRRw?editors=1100 在其中，我有一个铃铛图标，按下该图标会显示带有通知的下拉菜单。但是，根据屏幕尺寸，它从未真正放置在下拉菜单上的箭头指向钟形图标的中间..

我怎样才能做到这一点？本人对前端编程有点生疏，研究的时候一直没找到合适的方案

HTML

<ul class="nav nav-pills nav-justified">
  <li class="nav-item">
    <a class="nav-link active" aria-current="page" href="#">Active</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Much longer nav link</a>
  </li>
  <li class="nav-item">
    <a class="nav-link" href="#">Link</a>
  </li>
  <li class="nav-item notification-wrapper">
    <button class="notification-button">
      <i class="fas fa-bell"></i>
      <span>6</span>
    </button>
    <div class="notification-popup">
      <div class="notification-popup__header">
        <h3>Notifikationer</h3>
        <button title="marker alle som læst"><i class="fa-solid fa-check"></i></button>
      </div>
      <div class="notification-item">
        <ul>
          <li><i class='far fa-newspaper'></i></li>
          <li>
            <h2>Ny side oprettet</h2>
            <p>Tjek den ud her!</p>
            <a href="https://localhost:44310/medlem/nyheder/2022/nyhed-til-notification/">Nyhed til notification</a>
          </li>
          <li>
            <button class="" title="Makér denne som læst">
              <span><i class="fas fa-check-circle"></i></span>
            </button>
          </li>
        </ul>
      </div>
      <div class="notification-item">
        <ul>
          <li><i class='far fa-newspaper'></i></li>
          <li>
            <h2>Ny side oprettet</h2>
            <p>Tjek den ud her!</p>
            <a href="https://localhost:44310/medlem/nyheder/2022/nyhed-til-notification/">Nyhed til notification</a>
          </li>
          <li>
            <button class="" title="Makér denne som læst">
              <span><i class="fas fa-check-circle"></i></span>
            </button>
          </li>
        </ul>
      </div>
      <div class="notification-item">
        <ul>
          <li><i class='far fa-newspaper'></i></li>
          <li>
            <h2>Ny side oprettet</h2>
            <p>Tjek den ud her!</p>
            <a href="https://localhost:44310/medlem/nyheder/2022/nyhed-til-notification/">Nyhed til notification</a>
          </li>
          <li>
            <button class="" title="Makér denne som læst">
              <span><i class="fas fa-check-circle"></i></span>
            </button>
          </li>
        </ul>
      </div>
      <div class="notification-item">
        <ul>
          <li><i class='far fa-newspaper'></i></li>
          <li>
            <h2>Ny side oprettet</h2>
            <p>Tjek den ud her!</p>
            <a href="https://localhost:44310/medlem/nyheder/2022/nyhed-til-notification/">Nyhed til notification</a>
          </li>
          <li>
            <button class="" title="Makér denne som læst">
              <span><i class="fas fa-check-circle"></i></span>
            </button>
          </li>
        </ul>
      </div>
    </div>
  </li>
  <li class="nav-item">
    <a class="nav-link disabled">Disabled</a>
  </li>
</ul>

<nav>

</nav>

造型

$clr-white-1: #ecf0f1;
$clr-white-2: darken($clr-white-1, 5%);
$clr-t300: #444;
$clr-t500: #95a5a6;
$clr-p300: #111;
$clr-a300: #e74c3c; //#FF6A6A; //salmon
$container-shadow: 0.5rem 0.5rem 2rem 0 rgba(black, 0.2);
$h-gutter: 2rem;
$v-gutter: 0.75rem;

body {
  padding: 5% 0;
  margin: 0 0 50px 0;
  box-sizing: border-box;
  width: 100vw;
  height: 100vh;
  background: $clr-white-1;
  background: linear-gradient(30deg, $clr-white-2, $clr-white-1);
  font-family: "Lato", Arial, sans-serif;
  font-weight: 500;
  letter-spacing: 0.05rem;

  nav {
    position: absolute;
    left: 500px;
  }
}

.notification-wrapper {
  position: relative;
}

button.notification-button {
  position: relative;
  margin-right: 1em;
  border-radius: 5px;
  background: none;
  border: none;
  i {
    margin: 0.5rem;
  }
  &:nth-of-type(1) {
    i {
      background: -webkit-linear-gradient(300deg, #acccea, #6495ed);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
  }
  &:nth-of-type(2) i {
    background: -webkit-linear-gradient(300deg, #fff9ab, #00b8ff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
  }
  svg,
  .fa-bell {
    color: white;
    font-size: 28px;
  }
  span {
    position: absolute;
    user-select: none;
    cursor: default;
    font-size: 0.6rem;
    background: $clr-a300;
    width: 1.2rem;
    height: 1.2rem;
    color: $clr-white-1;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
    top: -0.33rem;
    right: 0;
    box-sizing: border-box;

    animation-name: scaleCount;
    animation-iteration-count: 1;
    animation-timing-function: all;
    animation-duration: 1s;
    animation-delay: 0s;

    @keyframes scaleCount {
      0% {
        transform: scale(0);
      }
      40% {
        transform: scale(1);
      }
      60% {
        transform: scale(0.5);
      }
      80% {
        transform: scale(1.25);
      }
    }
  }
}
.notification-popup {
  display: none;
  &.active {
    display: block;
  }
  &:before {
    // triangle
    content: "";
    position: absolute;
    top: 1px;
    right: 0;
    width: 0;
    height: 0;
    transform: translate(-1rem, -100%);
    border-left: 0.75rem solid transparent;
    border-right: 0.75rem solid transparent;
    border-bottom: 0.75rem solid white;
  }
  cursor: default;
  position: absolute;
  z-index: 999;
  top: 56px;
  left: -210px;
  width: 400px;
  font-weight: 300;
  background: white;
  border-radius: 0.5rem;
  box-sizing: border-box;
  box-shadow: $container-shadow;

  animation-name: dropPanel;
  animation-iteration-count: 1;
  animation-timing-function: all;
  animation-duration: 0.75s;

  &__header {
    h3 {
      text-transform: uppercase;
      font-size: 75%;
      font-weight: 700;
      color: #84929f;
      padding: $v-gutter * 2 $h-gutter;
      display: inline-block;
    }
    button {
      float: right;
      border: none;
      background: none;
      i {
        text-transform: uppercase;
        font-size: 22px;
        font-weight: 700;
        padding: $v-gutter * 2 $h-gutter;
        color: #84929f;
      }
    }
  }
  .notification-item {
    border-bottom: 2px solid lightgrey;
    display: block;
    overflow: hidden;
    width: 100%;
    padding: 10px 0;
    ul {
      li {
        float: left;
        list-style: none;
        padding: 5px;
        position: relative;
        &:first-child {
          i {
            font-size: 22px;
          }
        }
        &:last-child {
          right: $h-gutter;
          margin-left: $v-gutter;
          float: right;
        }
        button {
          &:hover {
            opacity: 0.8;
            cursor: pointer;
          }
          span {
            color: #b5c4d2;
            font-size: 140%;
            top: 50%;
            -webkit-transform: translateY(-50%);
            -ms-transform: translateY(-50%);
            transform: translateY(-50%);
            position: absolute;
          }
          background: none;
          border: none;
        }
      }
    }
  }
}

@keyframes dropPanel {
  0% {
    opacity: 0;
    transform: translateY(-100px) scaleY(0.5);
  }
}

为了完整起见，我的 js

$(".notification-button").on("click", function () {
  const ele = $(".notification-popup");
  if (ele.hasClass("active")) {
    console.log("remove active");
    ele.removeClass("active");
  } else {
    console.log("add active");
    ele.addClass("active");
  }
});
document.addEventListener(
  "click",
  function (event) {
    // If user either clicks X button OR clicks outside the modal window, then close modal by calling closeModal()
    if (
      event.target.closest(".notification-button") == null &&
      event.target.closest(".notification-popup") == null
    ) {
      console.log("remove active click outside");
      $(".notification-popup").removeClass("active");
    }
  },
  false
);

Answer 1

尝试使用 .notification-popup{ transform: center top; }

Answer 2

不要使用负 left 值定位弹出窗口，而是使用 right: 50%; 代替。这使您的右角与包含按钮的 li 的中间对齐。

然后添加transform: translateX(20px);以补偿大约一半的按钮宽度。或者使用 translateX(1.25em) 如果你想让它在字体大小方面保持动态。

通知下拉放置到按钮

notification dropdown placement to button

css

dropdown

web-frontend

placement