为什么在API 17中不推荐使用Android中的滑动抽屉？

I am new to android app development. Using API19 in android studio 1.2. I found sliding drawer attractive to use in my app. But when I used it in design layout, i got to know that it is deprecated. Hint says it is unsupported and use your own implementation.I am new to android app development. Using API1