mui 打开新页面createNew 为false时页面切换回来再切换回去就不行了

当createNew 为ture 的时候，两边可以来回切换但是打开很多新窗口，下面分别是首页和第二个页面的代码

<nav class="mui-bar mui-bar-tab">  
            <a class="mui-tab-item mui-active">  
                <span class="mui-icon  mui-icon-compose"></span>  
                <span class="mui-tab-label">说说</span>  
            </a>  
            <a class="mui-tab-item" id="info">  
                <span class="mui-icon  mui-icon-person"></span>  
                <span class="mui-tab-label">通讯录</span>  
            </a>  
            <a class="mui-tab-item">  
                <span class="mui-icon mui-icon-spinner-cycle mui-spin"></span>  
                <span class="mui-tab-label">发现</span>  
            </a>  
            <a class="mui-tab-item">  
                <span class="mui-icon mui-icon-gear"></span>  
                <span class="mui-tab-label">设置</span>  
            </a>  
        </nav>  
    </body>  
    <script type="text/javascript" charset="utf-8">  
        mui.init();  
        mui.plusReady(function() {  
            document.getElementById('info').addEventListener('tap', function() {  
                //打开关于页面  
                mui.openWindow({  
                    url: 'info.html',  
                    id: 'info.html',  
                    createNew: true,  
                    show:{  
                        aniShow: "slide-in-right",  
                        duration: 300,  
                        autoShow: true  
                    },  
                    waiting:{  
                        title: "正在加载，请稍后..."  
                    },  

                });  
            });  
        })  
    </script>  
第二张页面  
    <nav class="mui-bar mui-bar-tab">  
            <a class="mui-tab-item " id="index">  
                <span class="mui-icon  mui-icon-compose"></span>  
                <span class="mui-tab-label">说说</span>  
            </a>  
            <a class="mui-tab-item mui-active">  
                <span class="mui-icon  mui-icon-person"></span>  
                <span class="mui-tab-label">通讯录</span>  
            </a>  
            <a class="mui-tab-item">  
                <span class="mui-icon mui-icon-spinner-cycle mui-spin"></span>  
                <span class="mui-tab-label">发现</span>  
            </a>  
            <a class="mui-tab-item">  
                <span class="mui-icon mui-icon-gear"></span>  
                <span class="mui-tab-label">设置</span>  
            </a>  
        </nav>  
    </body>  
    <script type="text/javascript" charset="utf-8">  
        mui.init();  
        mui.plusReady(function() {  
            document.getElementById('index').addEventListener('tap', function() {  
                //打开关于页面  
                mui.openWindow({  
                    url: 'index.html',  
                    id: 'index.html',  
                    createNew: true,  
                    show: {  
                        autoShow: true,  
                        aniShow: "slide-in-left", //页面显示动画，默认为”slide-in-right“；  
                        duration: 100 //页面动画持续时间，Android平台默认100毫秒，iOS平台默认200毫秒；  
                    },  

                });  
            });  
        });  
</script>