如何为iPhone应用程序创建弯曲的UIButton

我想创建弯曲的UIButtons。如需演示，请查看此图片。

I want to create UIButtons which are curved. For demo look at this image.

我不想创建确切的按钮，但它们会像这个按钮一样有曲线。是否可以在iOS中创建这样的按钮？

I don't want to create the exact buttons, but they will have curve like this buttons. Is it possible to create such buttons in iOS?

谢谢。