本文实例讲述了Android编程判断网络连接是否可用的方法。分享给大家供大家参考,具体如下:
为了提高用户体验,我们在开发 android 应用的过程需要联网获取数据的时候我们首先要做的一步就是:
1.判断当前手机是否打开了网络
2.打开了网络是否可以上网
然后再去执行联网逻辑,避免没联网做不必要的工作!
通常情况下,我们是这样判断的
public static boolean isNetAvailable(Context context) { ConnectivityManager connectManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); return (connectManager.getActiveNetworkInfo() != null); }
但是这样只完成了第一步,判断网络是否打开,
注意:打开并不代表就可以上网,
观察发现 NetworkInfo 有一个方法:
复制代码 代码如下:NetworkInfo.isAvailable()
官方的解释是
Indicates whether network connectivity is possible. A network is unavailable when a persistent or semi-persistent condition prevents the possibility of connecting to that network. Examples include
The device is out of the coverage area for any network of this type.
The device is on a network other than the home network (i.e., roaming), and data roaming has been disabled.
The device's radio is turned off, e.g., because airplane mode is enabled.
Returns:
true if the network is available, false otherwise
他列举了几种网络已连接但不可以上网的情况,
所以我们这样改改就好了:
public static boolean isNetAvailable(Context context) { ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo info = manager.getActiveNetworkInfo(); return (info != null && info.isAvailable()); }
希望本文所述对大家Android程序设计有所帮助。