1

When using the "create" command provided by the cordova command line interface, the android project is created with the following code in the index.html file :

    <html>
<head>
    <meta charset="utf-8" />
    <meta name="format-detection" content="telephone=no" />
    <meta name="viewport" content="user-scalable=no, initial-scale=1, maximum-scale=1, minimum-scale=1, width=device-width, height=device-height, target-densitydpi=device-dpi" />
    <link rel="stylesheet" type="text/css" href="css/index.css" />
    <title>Hello World</title>
</head>
<body>
    <div class="app">
        <h1>Apache Cordova</h1>
        <div id="deviceready" class="blink">
            <p class="event listening">Connecting to Device</p>
            <p class="event received">Device is Ready</p>
        </div>
    </div>
    <script type="text/javascript" src="cordova.js"></script>
    <script type="text/javascript" src="js/index.js"></script>
    <script type="text/javascript">
        app.initialize();
    </script>
</body>

The index.js code has the following code:

    var app = {
// Application Constructor
initialize: function() {
    this.bindEvents();
},
// Bind Event Listeners
//
// Bind any events that are required on startup. Common events are:
// 'load', 'deviceready', 'offline', and 'online'.
bindEvents: function() {
    document.addEventListener('deviceready', this.onDeviceReady, false);
},
// deviceready Event Handler
//
// The scope of 'this' is the event. In order to call the 'receivedEvent'
// function, we must explicity call 'app.receivedEvent(...);'
onDeviceReady: function() {
    app.receivedEvent('deviceready');
},
// Update DOM on a Received Event
receivedEvent: function(id) {
    var parentElement = document.getElementById(id);
    var listeningElement = parentElement.querySelector('.listening');
    var receivedElement = parentElement.querySelector('.received');

    listeningElement.setAttribute('style', 'display:none;');
    receivedElement.setAttribute('style', 'display:block;');

    console.log('Received Event: ' + id);
}

};

All the cordova examples I have found on line include no code like this. I also haven't been able to find any explanations of this code in the documentation or stack overflow. It seems a complicated way to make sure no events are triggered before the DOM and cordova.js load. I would much appreciate it if anyone could point me to any explanations of this code.

4

1 回答 1

4

This is just a complicated way of triggering code after the device is ready.

You can do the same thing with

document.addEventListener('deviceready', onDeviceReady, false);

function onDeviceReady() {
    ....
}
于 2013-07-15T04:22:12.257 回答