遮罩层和消息框实现

Yukino 373 2021-12-29

遮罩层

  1. 原理:利用绝对定位和z-index,在所有组件上层添加一个窗口大小的div,利用js控制现实或隐藏
  2. 实现:
// html
<div id="mask" class="hidden"></div>

// css
#mask {
    width: 100vw;
    height: 100vh;
    position: absolute;
    /* 给遮罩层绝对定位 */
    z-index: 10;
    /* 设置z-index值 */
    background-color: rgba(0, 0, 0, 0.4);
}

.hidden {
    display: none;
}

// js 
let mask = document.getElementById("mask");
mask.setAttribute("class", ""); //显示遮罩层
mask.setAttribute("class", "hidden");   //隐藏遮罩层

消息框

  1. 原理:利用绝对定位和z-index,在遮罩层上层添加一个div,利用js控制现实或隐藏、click事件以及文本内容
  2. 实现:
// html
<div id="msg-box" class="hidden">
    <p id="msg"></p>
    <button id="msg-box-btn" onclick="hideMsg()">知道了</button>
</div>

// css
#msg-box {
  width: 70vw;
  background-color: black;
  z-index: 11;
  position: absolute;
  margin-top: 38vh;
  margin-left: 15vw;
  border-radius: 8px;
  color: white;
  text-align: center;
  font-size: 26px;
}
#msg-box p {
  margin-top: 5.5vh;
  margin-bottom: 4.5vh;
}
#msg-box button {
  font-size: 18px;
  width: 50vw;
  height: 5.5vh;
  margin-bottom: 4.5vh;
  background-color: #e62528;
  color: white;
  outline: none;
  border: 0px;
  text-align: center;
  border-radius: 6px;
}

// js
let msgBox = document.getElementById("msg-box");
msgBox.setAttribute("class", "");   // 显示消息框
document.getElementById("msg").innerText = "msg";   // 设置文本内容

整体实现(可直接使用)

// html
<!-- 遮罩层 -->
<div id="mask" class="hidden"></div>

<div id="msg-box" class="hidden">
    <p id="msg"></p>
    <button id="msg-box-btn" onclick="hideMsg()">知道了</button>
</div>

// css 
/* 遮罩层样式设置 */
#mask {
  width: 100vw;
  height: 100vh;
  position: absolute;
  /* 给遮罩层绝对定位 */
  z-index: 10;
  /* 设置z-index值(要小于弹出框) */
  background-color: rgba(0, 0, 0, 0.4);
}
#msg-box {
  width: 70vw;
  background-color: black;
  z-index: 11;
  position: absolute;
  margin-top: 38vh;
  margin-left: 15vw;
  border-radius: 8px;
  color: white;
  text-align: center;
  font-size: 26px;
}
#msg-box p {
  margin-top: 5.5vh;
  margin-bottom: 4.5vh;
}
#msg-box button {
  font-size: 18px;
  width: 50vw;
  height: 5.5vh;
  margin-bottom: 4.5vh;
  background-color: #e62528;
  color: white;
  outline: none;
  border: 0px;
  text-align: center;
  border-radius: 6px;
}

// js
/*
* 弹出提示框
* msg: 消息文本
* btnVisiable: 是否显示按钮
* maskCloseable: 是否可以点击遮罩层关闭消息框
*/
function msg(msg, btnVisiable = true, maskCloseable = true) {
    let mask = document.getElementById("mask");
    let msgBox = document.getElementById("msg-box");
    let msgBoxBtn = document.getElementById("msg-box-btn");
    mask.setAttribute("class", "");
    if(maskCloseable) {
        mask.setAttribute("onclick", "hideMsg()");
    }
    else {
        mask.setAttribute("onclick", "");
    }
    msgBox.setAttribute("class", "");
    if(btnVisiable) {
        msgBoxBtn.setAttribute("class", "");
    }
    else {
        msgBoxBtn.setAttribute("class", "hidden");
    }
    document.getElementById("msg").innerText = msg;
}

/*
* 隐藏提示框
*/  
function hideMsg() {
    document.getElementById("mask").setAttribute("class", "hidden");
    document.getElementById("msg-box").setAttribute("class", "hidden");
    document.getElementById("msg").innerText = "";
}

# 前端