【产品Bug】将checkbox放在label中，另有button都在同一个表单域中，先点击button，之后每次点击checkbox都会触发button的事件，而不会触发checkbox的事件

详细问题描述
我是在移动web项目中使用的mui，因为mui封装了移动端tap事件，且提供了比较友好的UI。
在页面中使用表单，表单中有button(多个)，有checkbox，为了方便点击，将checkbox放在label中，但是先点击button(任意一个)，然后在点击checkbox，就会触发刚才点击的button的事件，而checkbox的状态将不会再变化，貌似不会再响应checkbox的事件，在空白处点击一下，就会恢复正常，如此重复。
页面主体代码：

<header class="mui-header mui-bar mui-bar-nav">  
        <a class="mui-action-back mui-btn mui-btn-link mui-pull-left">返回</a>  
        <h1 class="mui-title">开启一键投标</h1>  
    </header>  
    <div class="mui-content mui-scroll-wrapper">  
        <div class="mui-scroll">  
            <div class="mui-content-padded">  
                <form action="" method="post" novalidate="novalidate">  
                    <div class="form-group">  
                        <div class="mui-h4" style="line-height:2;margin-bottom:15px">用户手机号：***********</div>  
                    </div>  
                    <div class="form-group">  
                        <input type="number" name="maxMoney" class="orange" min="0" placeholder="请输入您的最高限额">  
                    </div>  
                    <div class="form-group">  
                        <input type="password" name="payPwd" class="orange" placeholder="请输入您的支付密码">  
                    </div>  
                    <div class="form-group">  
                        <div class="mui-row">  
                            <div class="mui-col-xs-8">  
                                <input type="text" name="capt" class="orange" placeholder="请输入图片验证码">  
                            </div>  
                            <div class="mui-col-xs-4 mui-text-right">  
                                <a id="updateCapt" style="display:block;"><img src="。。。" width="90%" height="40"></a>  
                            </div>  
                        </div>  
                    </div>  
                    <div class="form-group">  
                        <div class="mui-row">  
                            <div class="mui-col-xs-8">  
                                <input type="text" name="phoneCapt" class="orange" placeholder="请输入短信验证码">  
                            </div>  
                            <div class="mui-col-xs-4 mui-text-right">  
                                <button type="button" id="getCode" class="mui-btn mui-btn-red orange mui-btn-outlined" style="padding:0;width:90%;line-height:38px">获取验证码</button>  
                            </div>  
                        </div>  
                    </div>  
                    <p id="getsoundcode" style="margin:0 0 10px;display:none">  
                        <span style="padding:5px 10px;color:#777;border:1px solid #F1D793;background-color:#FFFFE3;">若未收到验证码，请点击 <a style="color:#FF0000;">语音获取</a></span>  
                    </p>  
                    <div class="form-group">  
                        <label><input type="checkbox" checked="checked" name=""> 同意</label>  
                        <a href="。。。">《服务协议》</a>  
                    </div>  
                    <div class="form-group" style="margin-top:15px;">  
                        <button type="submit" class="mui-btn mui-btn-red orange mui-btn-block">确定</button>  
                    </div>  
                </form>  
            </div>  
        </div>  
    </div>  
    <div id="msgModal" class="mui-modal mui-dialog">  
        <div class="mui-modal-header">  
            <div class="mui-modal-title">系统提示</div>  
        </div>  
        <div class="mui-modal-body">  
            <div class="msg-container mui-text-center"></div>  
        </div>  
        <div class="mui-modal-footer">  
            <a href="#msgModal" class="mui-btn">确定</a>  
        </div>  
    </div>  
    <div class="mui-backdrop mui-dialog-mask"></div>

功能js代码如下：

!function(window, $){  
    'use strict'; // 启用严格模式  
    // jquery 静态方法扩展  
    $.extend({  
        /**  
         * json数据加载器  
         * @param param [Object] 同ajax的参数  
         */  
        loader: function (param){  
            param = param || {};  
            var a = param.success || function(){},  
            b = param.error || function(a){  
                alert(a)  
            },  
            c = $.extend({  
                type: 'post',  
                dataType: 'json',  
                cache: false,  
                contentType: 'application/x-www-form-urlencoded;charset=utf-8',  
                complete: function(r){  
                    var a = r.getResponseHeader && r.getResponseHeader('sessionstatus');  
                    a == 'timeout' && (location.href= '。。。')  
                }  
            }, param);  
            c.success = function(c){  
                var f = !1,  
                m = '\u670d\u52a1\u5668\u65e0\u54cd\u5e94',  
                p = {},  
                d = c;  
                if(c) {  
                    if(c.status) {  
                        f = c.status.code === '0000';  
                        m = c.status.msg||'\u8bf7\u6c42\u6210\u529f';  
                        d = c.infoArr || c.infobj || {};  
                        p = c.page || {}  
                    } else {  
                        f = !0;  
                        m = '\u6570\u636e\u52a0\u8f7d\u5b8c\u6210'  
                    }  
                }  
                f ? a.call(this, d, p, m) : b.call(this, m);  
            };  
            return $.ajax(c)  
        }  
    });  

    // jquery对象方法扩展  
    $.extend($.fn, {  
        /**  
         * 将表单元素序列化成对象  
         */  
        serializeObject: function(){  
            var o = {};  
            $.each(this.serializeArray(), function(){  
                if(o[this.name]) {  
                    o[this.name] += ',' + this.value  
                } else {  
                    o[this.name] = this.value  
                }  
            });  
            return o  
        },  
        /**  
         * 通过name获取表单元素的值  
         */  
        getValue: function(n) {  
            return this.serializeObject()[n]  
        },  
        /**  
         * 通过name为表单元素赋值  
         */  
        setValue: function(n, v) {  
            var o = this.find('[name="' + n + '"]').val(v);  
            return this  
        },  
        /**  
         * 表单元素中name和object的key对应载入value  
         */  
        load: function(o){  
            for(var k in o) o.hasOwnProperty(k) && this.setValue(k, o[k]);  
            return this  
        }  
    });  
}(window, jQuery);  
!function(mui, $, window, document, undefined){  

    var methods = {  
        init: function(){  
            mui.init({swipeBack: true});  
            mui('.mui-scroll-wrapper').scroll();  
            this.path = window.contextPath;  
            this.mask = mui.createWaiting();  
            this.btn = document.querySelector('#getCode');  
            this.captBtn = document.querySelector('#updateCapt');  
            this.msgModal = document.querySelector('#msgModal');  
            this.dismiss = this.msgModal.querySelector('.mui-btn');  
            this.form = document.querySelector('.mui-content form');  
            this.voiceBtn = document.querySelector('#getsoundcode');  
            this.checkbox = this.form.querySelector('[type=checkbox]');  
            this.shaild = function(){return false};  
            this.msgCB = undefined;  
            this.initEvent();  
        },  
        initEvent: function(){  
            var self = this;  
            this.btn.addEventListener('tap', function(e){  
                e.preventDefault();  
                self.getVerfiCode('。。。', function(){  
                    self.voiceBtn.style.display = 'block';  
                    self.countdown()  
                })  
            });  
            this.captBtn.addEventListener('tap', function(e){  
                e.preventDefault();  
                this.querySelector('img').setAttribute('src', self.path + '。。。' + new Date().getTime())  
            });  
            this.dismiss.addEventListener('tap', function(e){  
                self.msgCB && self.msgCB();  
            });  
            this.form.addEventListener('submit', function(e){  
                e.preventDefault();  
                self.send()  
            });  
            mui(this.voiceBtn).on('tap', 'a', function(e){  
                e.preventDefault();  
                self.getVerfiCode('。。。')  
            });  
            this.checkbox.addEventListener('change', function(e){  
                self.form.querySelector('[type=submit]').disabled = !e.target.checked;  
            });  
            document.addEventListener('touchstart', this.shaild, false);  
            document.oncontextmenu = this.shaild;  
        },  
        msgAlert: function(m, c){  
            this.msgCB = c;  
            this.msgModal.classList.add('mui-active');  
            this.msgModal.querySelector('.msg-container').innerHTML = m || '';  
        },  
        send: function(){  
            var self = this;  
            var data = $(this.form).serializeObject();  
            if(this.validate(data)) {  
                this.mask.show();  
                $.loader({  
                    url: this.path + '。。。',  
                    data: data,  
                    success: function(r, p, m){  
                        self.mask.close();  
                        self.msgAlert(m, function(){  
                            location.href = self.path + '。。。'  
                        })  
                    },  
                    error: function(m){  
                        self.mask.close();  
                        self.msgAlert(m)  
                    }  
                })  
            }  
        },  
        validate: function(data){  
            if(!data.maxMoney) {  
                return !!this.msgAlert('请输入最高限额')  
            }  
            if(!/^[1-9]\d*$/.test(data.maxMoney)) {  
                return !!this.msgAlert('最高限额格式错误，请重新输入')  
            }  
            if(data.maxMoney < 1000){  
                return !!this.msgAlert('最高投标额应不小于1000元')  
            }  
            if(!data.payPwd) {  
                return !!this.msgAlert('请输入支付密码')  
            }  
            var capt = this.validCapt(data.capt);  
            if(!capt) return capt;  
            if(!data.phoneCapt) {  
                return !!this.msgAlert('请输入短信验证码')  

	

  

            }  
            return true  
        },  
        getVerfiCode: function(url, fn){  
            var self = this;  
            var capt = $(this.form).getValue('capt');  
            if(this.validCapt(capt)) {  
                this.mask.show();  
                $.loader({  
                    url: this.path + url,  
                    data: {  
                        type: '0',  
                        capt: capt  
                    },  
                    success: function(r, p, m){  
                        self.mask.close();  
                        self.msgAlert(m);  
                        fn && fn()  
                    },  
                    error: function(m){  
                        self.mask.close();  
                        self.msgAlert(m)  
                    }  
                })  
            }  
        },  
        validCapt: function(capt){  
            if(!capt) {  
                return this.msgAlert('请输入图片验证码') && !1  
            }  
            if(!/^[0-9A-Za-z]{4}$/.test(capt)) {  
                return this.msgAlert('验证码输入错误！') && !1  
            }  
            return !!capt  
        },  
        countdown: function(){  
            var self = this;  
            if(this.interval == undefined) this.interval = 60;  
            if(this.interval-- > 0) {  
                this.btn.disabled = true;  
                this.btn.innerText = this.interval + '秒后重试';  
                setTimeout(function(){  
                    self.countdown()  
                }, 1000)  
            } else {  
                this.btn.disabled = false;  
                this.btn.innerText = '获取验证码'  
            }  
        }  
    };  

    mui.ready(function(){methods.init()})  

}(mui, jQuery, window, document, undefined);

我是在Chrome控制台仿真模式下调试，真机上也测试了，同样的问题