您在委派事件绑定内部发生了标准事件绑定.这意味着每次外部事件触发时，内部绑定都将被绑定.

You've got a standard event binding happening inside of a delegated event binding. That means that the inner-binding will be bound every time the outer-event fires.

因此，基本上，每次pagebeforeshow为任何伪页面触发时，您都将重新绑定您的tap事件处理程序.每次导航到另一个页面时，您都会创建另一个内部绑定，因此会收到多个警报.

So basically you're re-binding your tap event handler each time the pagebeforeshow fires for any pseudo-page. Each time you navigate to another page you're creating another inner-binding so you're getting multiple alerts.

一个好的解决方法是为pageinit页面事件创建一个委托事件处理程序，并在该事件处理程序中进行内部绑定. pageinit事件每个伪页面仅触发一次，因此您将不必继续添加不必要的事件处理程序.

A good fix is to create a delegated event handler for the pageinit page-event and do the inner-binding in that event handler. The pageinit event only fires once per pseudo-page so you won't keep adding more event handlers unnecessarily.

例如:

$(document).on('pageinit', '.ui-page',function(){
    var db       = window.openDatabase("mydb", "1.0", "MyDB", 1000000),
        url      = window.location.href,
        filename = url.substring(url.lastIndexOf('/')+1);

    switch (filename) {
        case "index.html":
            $("#add").tap(function(e){
                if ($("#info").val() == "") {
                    navigator.notification.alert("The info cannot be blank!", function(){}, "Error", "Okay, got it!");
                } else {
                    db.transaction(addToDb, errorCB, addedToDb);
                }
            });
            break;
        case "sample.html":
            break;
    }
});

您会注意到，我将.on()用作委派的事件处理程序，而不是已贬值的.live().

You'll notice I used .on() for my delegated event handler instead of the depreciated .live().