判断是否有网，判断网络连接，跳转至设置

public class NetTypeUtils {

public static boolean isConn(Context context){

    //1.得到网络判断的系统服务
    ConnectivityManager manager=(ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    //2.得到网络信息类
    NetworkInfo info=manager.getActiveNetworkInfo();
    if(info!=null && info.isAvailable()){
        return true;
    }else{
        return false;

    }


}

public static  void openNetSettingDg(final Context context){
    AlertDialog.Builder builder=new AlertDialog.Builder(context);
    builder.setTitle("设置网络");
    builder.setMessage("是否要打开网络连接？");
    builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            //跳转到设置页面
            Intent intent;
            // 先判断当前系统版本
            if(android.os.Build.VERSION.SDK_INT > 10){  // 3.0以上
                intent = new Intent(android.provider.Settings.ACTION_WIRELESS_SETTINGS);
            }else{
                intent = new Intent();
                intent.setClassName("com.android.settings", "com.android.settings.WirelessSettings");
            }
            context.startActivity(intent);

        }
    });
    builder.setNegativeButton("取消",null);

    builder.show();

}

}