Add some attributes for customize this View

[LiuShuaiQ]

I think this attibutes may be used.
angleRange attributes - the angle range, the default value is 360.
showClickAnim attributes - this switch of click animation.
centerButtonGravity attributes - for set Gravity for centerButton, the default value is CENTER.

[ImangazalievM]

Hello! Good job! But can you give examples of cases where we can use centerButtonGravity and showClickAnim attributes, please?

I guess showClickAnim implementation has a bug. When I use this attribute with false value, the menu does not close on a button click.

[LiuShuaiQ]

Yes, showClickAnim implementation indeed has a bug. When this attribute with false value, the OnItemClickListener does not callback! But I think close the menu should be placed inside the OnItemClickListener, the click behavior is determined by the developer.

Now I fixed this bug, and update sample code for this.

[ImangazalievM]

@LiuShuaiQ Thank you for your contribution!