Here are some things that you need to know. The
Do It Result is the value that it will return, or show.
App Inventor colors.
Color blocks in App Inventor have their own drawer, separated from Math, but color blocks are really just numbers. App Inventor uses numbers to represent colors. For example, the color Red is just -65536.
However, you can also split a color to make it an RGB list. In the list, the first item is the R value, the second item is the G value, and that the third value is the B value. There might be a fourth value, which is the Alpha value, which decides how bright a color should be.
From this list of
255, 0, 0, 255, the RGB value is (255, 0, 255). If you want to get a specific value, such as B, you can use:
because the B value is the third item in the list.
With that knowledge, here is a demo.