mui底部导航栏跳转页面,怎么加载前实现等待效果

//部分html代码  
   <a href="appindex.html" class="mui-tab-item mui-active">  
        <span class="mui-icon mui-icon-home"></span>  
        <span class="mui-tab-label">首页</span>  
    </a>

//js代码  
mui.plusReady(function () {  
        var self = plus.webview.currentWebview();  
        //var userName = self.name;  
        for (var i = 0; i < subpages.length; i++) {  
            var sub = plus.webview.create(subpages[i], subpages[i], subpagesStyle);  
            sub.hide();  
            self.append(sub);  
        }  
        plus.webview.show(subpages[0]);  
    });  
//点击事件  
    mui(".mui-bar-tab").on("tap", "a", function (e) {  
        //var nwaiting = plus.nativeUI.showWaiting();  
        var targerPage = this.getAttribute('href');  
        plus.webview.show(targerPage, "fade-in");  
    });  

请问下这种方式怎么加载子页面之前显示plus.nativeUI.showWaiting()效果,加载完成后隐藏  
大佬的可以联系我qq 1310511285 ,万分感谢