Question

这是我的代码，它假设处理我的phonegap应用程序的设备和网络事件

define(['jquery', 'knockout'], function ($, ko) {
var deviceHandler = {
    Online: null,
    Offline: null,
    OnNavigateBack: null
};

function HandleBackClick() {
    return deviceHandler.OnNavigateBack;
}

function HandleOnlineState() {
    return deviceHandler.Online;
}

function HandleOfflineState() {
    return deviceHandler.Offline;
}

document.addEventListener('online', HandleOnlineState, false);
document.addEventListener('offline', HandleOfflineState, false);
document.addEventListener('backbutton', HandleBackClick, false);

return deviceHandler;
});

当我导入此模块时，我以这种方式将自己的功能分配给devicecs在线事件

MobileDevice.Online = function() {
            alert("we have updated information..");
        };

但它永远不会被调用。任何人都可以帮我这个模块吗？还有一件事要做：在设备就绪事件之后，这个赋值会被不同地调用。

Answer 1

您没有调用事件处理程序 - 而是返回引用。试试这个：

function HandleBackClick() {
    return deviceHandler.OnNavigateBack();
}
function HandleOnlineState() {
    return deviceHandler.Online();
} 
function HandleOfflineState() {
    return deviceHandler.Offline();
}

当然，您应该处理您可能没有定义处理程序或者您正在发送参数的情况。我已经把它变得更通用了，但如果你愿意，你可以忽略它。

function _callEventHandler ( eventHandler ) {
    var handler;
    var args = Array.prototype.slice.call(arguments, 1); // skip the first parameter
    if (typeof deviceHandler[eventHandler] !== "undefined") {
        handler = deviceHandler[eventHandler];
        if (typeof handler === "function") {
            handler.apply (this, args);
        } else {
            console.log ( "WARNING: event handler isn't a function", eventHandler );
        }
    } else {
        console.log ( "WARNING: event handler isn't defined", eventHandler );
    }
}

// a bit more generic so you can add events easily without duplicating a lot of code
// down the line. Of course, it might be better to simply register for the event
// when the handler is assigned -- you could use properties for that
[ [ "online", "Online" ],
  [ "offline", "Offline" ],
  [ "backbutton", "OnNavigateBack" ] 
].forEach ( function ( evt )
    {
        document.addEventListener ( evt[0], _callEventHandler.bind(this, evt[1]), false );
    }
);

// if you don't want to be that generic you can still:
// document.addEventListener ( "online", _callEventHandler.bind(this, "Online"), false );
// ...

Phonegap设备AMD模块

1 个答案: