我正在构建一个Cordova应用程序,在其中我使用Cordova网络信息插件org.apache.Cordova.network-information。过去几天,我在safari中调试时,在web检查器中遇到了这个奇怪的错误,其中说"typeerror‘undefined’不是对象(正在评估‘navigator.connection.type’)"。在初始加载期间,它运行良好,但在进一步导航时在应用程序中显示此错误并冻结应用程序。在iOS 8中,它经常出现,但在Android棒棒糖中,它偶尔会出现。我已经尝试了所有关于这方面的建议或帖子,但没有任何结果。我使用的是Cordova版本4.3,iOS 8.1。非常感谢任何帮助抱歉无法发布任何关于此的图片,因为我没有足够的声誉来发布
function checkConnection() {
alert(navigator.connection.type);
var networkState = navigator.connection.type;
var states = {};
states[Connection.UNKNOWN] = 'Unknown connection';
states[Connection.ETHERNET] = 'Ethernet connection';
states[Connection.WIFI] = 'WiFi connection';
states[Connection.CELL_2G] = 'Cell 2G connection';
states[Connection.CELL_3G] = 'Cell 3G connection';
states[Connection.CELL_4G] = 'Cell 4G connection';
states[Connection.CELL] = 'Cell generic connection';
states[Connection.NONE] = 'No network connection';
if(networkState == Connection.UNKNOWN || networkState == Connection.NONE){
navigator.notification.alert('No Network Available',null,"Warning");
sessionStorage.setItem('UserID',"");
$.mobile.changePage("#loginPage", {
transition: 'none',
showLoadMsg: true
});
return false;
}else{
return true;
}
}
在我的例子中,问题是我调用了device ready
之外的函数所以这样做解决了我的问题:
document.addEventListener("deviceready", function(){
// do your navigator.connection.type stuff here
}, false);
检查您是否已声明这些
<feature name="NetworkStatus">
<param name="android-package" value="CDVConnection" />
</feature>
网络状态将是功能名称,值将是您的类名。
在Android Manifest中,
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
华硕检查cordova_plugin.js
cordova.define('cordova/plugin_list', function(require, exports, module) {
module.exports = [{
"file": "plugins/org.apache.cordova.dialogs/www/notification.js",
"id": "org.apache.cordova.dialogs.notification",
"merges": ["navigator.notification"]
}, {
"file": "plugins/org.apache.cordova.network-information/www/network.js",
"id": "org.apache.cordova.network-information.network",
"clobbers": ["navigator.connection", "navigator.network.connection"]
}];
module.exports.metadata = // TOP OF METADATA
{
"org.apache.cordova.device": "0.2.8",
"org.apache.cordova.network-information": "0.2.7"
}
});
我在使用cordova插件网络信息时遇到了同样的问题。我注意到,尽管在"deviceready"被激发后被调用,navigator.connection.type对象仍然未定义。我的解决方法是将调用延迟200ms,之后对象就可以使用了。
function checkConnection(){
try{
console.log(navigator.connection.type);
}
catch(e){
alert("error : "+e);
}
setTimeout(function(){
var networkState = navigator.connection.type;
console.log(networkState);
var states = {};
states[Connection.UNKNOWN] = 'Unknown connection';
states[Connection.ETHERNET] = 'Ethernet connection';
states[Connection.WIFI] = 'WiFi connection';
states[Connection.CELL_2G] = 'Cell 2G connection';
states[Connection.CELL_3G] = 'Cell 3G connection';
states[Connection.CELL_4G] = 'Cell 4G connection';
states[Connection.CELL] = 'Cell generic connection';
states[Connection.NONE] = 'No network connection';
// alert('Connection type: ' + states[networkState]);
if(states[networkState] == "No network connection"){
window.location.assign("lostConnection.html");
}
}, 200);
}
因此,"try/catch"序列将因未定义的对象而失败,但200毫秒后,对navigator.connection.type的调用成功了,对我来说还好!