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我正在创建 Phonegap 应用程序，并想检测是否有人按下了 android 设备的硬件菜单按钮。

这是我的简单 HTML 代码，与 helloworld 应用程序中的代码几乎相同：

<!DOCTYPE html>
<!--
    Licensed to the Apache Software Foundation (ASF) under one
    or more contributor license agreements.  See the NOTICE file
    distributed with this work for additional information
    regarding copyright ownership.  The ASF licenses this file
    to you under the Apache License, Version 2.0 (the
    "License"); you may not use this file except in compliance
    with the License.  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing,
    software distributed under the License is distributed on an
    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
     KIND, either express or implied.  See the License for the
    specific language governing permissions and limitations
    under the License.
-->
<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>PhoneGap</h1>
        <div id="deviceready" class="blink">
            <p class="event listening">Connecting to Device</p>
            <p class="event received">Device is Ready</p>
        </div>

        <div id="testapp">Here</div>
    </div>
    <script type="text/javascript" src="phonegap.js"></script>
    <script type="text/javascript" src="js/index.js"></script>
    <script type="text/javascript">
        app.initialize();
    </script>
    </body>
</html>

这是JS，它具有以下逻辑：

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
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);
    document.addEventListener('menubutton', this.onMenuButton, 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');
    },
    onMenuButton:  function(){
    app.menuPressed();
    },
    // 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);
    },
    menuPressed: function(){
document.getElementById("testapp").innerHTML = "it is in menu div";
    }
};

在这里它正在检测何时检测到 deviceready，但未检测到menubutton检测。我究竟做错了什么？

4

2 回答 2

1

我通过在函数定义中省略参数ev破坏了我的整个应用程序。不知道为什么，但是当我把它放回去时它修复了一切！这是Phonegap 3.1.0。

document.addEventListener("menubutton", native_menu_button, false);

function native_menu_button(ev) {
    //whatever
}
于 2014-02-03T10:59:32.927 回答
1

我找到了它没有检测到menubutton事件的原因。我实际上在错误的地方附加了事件监听器。

这一行：

document.addEventListener('menubutton', this.onMenuButton, false);

in 而不是 bindEvents，它应该在onDeviceReady函数中，因为onDeviceReady我们可以附加事件。但是我们不能将它附加bindEvents为bindEvents只执行一次，app.initialize从index.html.

让我知道是否有人需要了解更多信息，以便它对您有用。

于 2013-10-06T01:32:12.013 回答