Vue.js--下拉菜单组件

冷不防 2021-08-13 18:35 501阅读 0赞

#### 效果 ####

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NvbGRfX19wbGF5_size_16_color_FFFFFF_t_70]\#\#\#\# 入口页面 index.html

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <title>可从外部关闭的下拉菜单</title>
        <link rel="stylesheet" type="text/css" href="style.css">
    </head>
    <body>
        <div id="app" v-cloak>
            <div class="main" v-clickoutside="handleClose">
                <button @click="show = !show">点击显示下拉菜单</button>
                <div class="dropdown" v-show="show">
                    <p>下拉框的内容，点击外面区域可以关闭</p>
                </div>
            </div>
        </div>
        <script src="https://unpkg.com/vue/dist/vue.js"></script>
        <script src="clickoutside.js"></script>
        <script src="index.js"></script>
    </body>
    </html>

#### 根实例 index.js ####

var app = new Vue({ 
        el: '#app',
        data: { 
            show: false
        },
        methods: { 
            handleClose () { 
                this.show = false;
            }
        }
    });

#### 下拉框组件 clickoutside.js ####

Vue.directive('clickoutside',{ 
        bind: function (el, binding, vnode) { 
            function documentHandler(e) { 
                if(el.contains(e.target)){ 
                    return false;
                }
                if(binding.expression){ 
                    binding.value(e);
                }
            }
            el.__vueClickOutside__ = documentHandler;
            document.addEventListener('click',documentHandler);
        },
        unbind: function (el, binding) { 
            document.removeEventListener('click', el.__vueClickOutside__);
            delete el.__vueClickOutside__;
        }
    });

#### 样式表 ####

[v-cloak]{ 
        display: none;
    }
    .main{ 
        width: 125px;
    }
    button{ 
        display: block;
        width: 100%;
        color: #fff;
        background-color: #39f;
        border: 0;
        padding: 6px;
        text-align: center;
        font-size: 12px;
        border-radius: 4px;
        cursor: pointer;
        outline: none;
        position: relative;
    }
    button:active{ 
        top:1px;
        left: 1px;
    }
    .dropdown{ 
        width:100%;
        height: 150px;
        margin: 5px 0;
        font-size: 12px;
        background-color: #fff;
        border-radius: 4px;
        box-shadow: 0 1px 6px rgba(0,0,0,.2);
    }
    .dropdown p{ 
        display: inline-block;
        padding: 6px;
    }

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NvbGRfX19wbGF5_size_16_color_FFFFFF_t_70]: /images/20210813/a4f28157f6d44c56b82ef85e57637af1.png