public static void checkNetworkState(final Activity activity) {

// 1，判断有没有网

ConnectivityManager manager = (ConnectivityManager) activity

.getSystemService(Context.CONNECTIVITY_SERVICE);

NetworkInfo networkInfo = manager.getActiveNetworkInfo();

if (networkInfo == null) {

// 2,显示dialog

AlertDialog.Builder dialog = new AlertDialog.Builder(activity);

dialog.setMessage("亲，现在没网");

dialog.setPositiveButton("打开网络", new OnClickListener() {




@Override

public void onClick(DialogInterface dialog, int which) {

// 3,打开系统自带的网络设置activity

Intent intent = new Intent(

Settings.ACTION_WIRELESS_SETTINGS);

activity.startActivity(intent);

}

});




dialog.setNegativeButton("取消", new OnClickListener() {



@Override

public void onClick(DialogInterface dialog, int which) {

dialog.cancel();

}

});



dialog.show();



}