No, to successfully manage your weight with Xenical, you will use it in conjunction with a low-fat, balanced diet. You should also engage in regular exercise and limit alcohol intake. You can read more on this here.
Once you have stopped taking this medication, it is important to continue with these changes so that weight loss can be maintained.
If you do gain weight again after stopping this treatment, it may be appropriate to consider another course of xenical or other weight loss treatments, depending on your individual situation.