[Feature Request] Added option to show different icon when main button is clicked

[jooy2]

Thanks for making such a great library.

Currently, only the background/foreground color can be changed when the main button of the fab is clicked, and the icon cannot be specified separately for the open or closed state. Only one icon can be specified.

Are there any options currently available for this, or plans to add more in the future?
The image (gif) below is an example of changing the icon. Notice the button at the bottom.

Image Source: https://gfycat.com/en/colorfulselfreliantamericanindianhorse

[janoschp]

Nah not planing to, but if you want you can do it yourself and open a pr. I'd have a look at it.