Android 判断连接的wifi是否能访问网络

如果只是想检测网络是否连接，则直接使用 isNetworkConnected()
如果想检测网络连通性（是否能访问网络），则 isNetworkConnected() 与 isNetworkOnline() 结合使用。

private boolean isNetworkConnected() {
    ConnectivityManager connMgr = (ConnectivityManager)
            getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
    return (networkInfo != null && networkInfo.isConnected());
}
 
public boolean isNetworkOnline() {
    Runtime runtime = Runtime.getRuntime();
    try {
        Process ipProcess = runtime.exec("ping -c 3 www.baidu.com");
        int exitValue = ipProcess.waitFor();
        Log.i("Avalible", "Process:"+exitValue);
        return (exitValue == 0);
    } catch (IOException | InterruptedException e) {
        e.printStackTrace();
    }
    return false;
}