Buttons To Control Gradients

Can you show your code that explains what you have done till now and what you can do now?

This is the code so far. Some lines may seem irrelevant, but thats just because I'm planning on doing something with them later on.

Staying on topic, what I want to do is have a button that, when pressed, changes the gradient from a set list of gradients.

For example, the current result looks like this:

And then when the button is pressed, I want it to look like this with a smooth transition:

Oh nevermind, I just realized I can make multiple views and have buttons transition through those