Your use of while True basically means your light pattern will repeat forever once triggered, and the code will never reach the next if statement.
A while loop means you’re telling the interpreter to “keep doing this thing over and over.” A while True loop will always repeat while True is True, and since True is always True, that means it can only be broken out of with a break, return or by exiting the code altogether.
By way of example, if I told you to hop on your left leg with your eyes shut and your fingers in your ears until instructed to do otherwise, you’d never hear or see me telling you to stop.
If I told you to hop 10 times, you’d hop ten times and then be ready to receive your next instruction. This would be approach 1, and in pseudocode it would look something like:
forever:
if touch one is pressed:
run my first light pattern 10 times
if touch two is pressed
run my second light pattern 10 times
So after 10 runs of either light pattern, your program would be back to checking if either touch one or two is pressed. At the moment, it’s stuck permenantly.
An alternate approach is to split your code into two logical processes. Imagine I’ve told you to “hop on your left leg leg with your eyes shut and your fingers in your ears”, and I’ve told you to keep doing that until George, our hypothetical other process, pokes you with a stick.
George is instructed to do something like this:
forever:
if touch one is pressed:
poke pi2003 with a stick
if touch two is pressed:
poke pi2003 with a stick
So now every time a button is pressed, either button in this instance, despite me not being able to tell you what to do by waving my arms or shouting, George will poke you with his stick you’ll swap from hopping on your left leg to your right leg.
Explorer HAT has a George, albeit not in so many words, you can ask Explorer HAT to watch a button for you and run some code:
import explorerhat
import time
pattern = 0
def change_pattern(channel, event):
global pattern
pattern = channel
explorerhat.touch.pressed(change_pattern)
print("Press a button to start a pattern")
while True:
if pattern = 1:
explorerhat.light.blue.on()
time.sleep(0.2)
explorerhat.light.yellow.on()
explorerhat.light.blue.off()
time.sleep(0.2)
explorerhat.light.yellow.off()
explorerhat.light.red.on()
time.sleep(0.2)
explorerhat.light.red.off()
explorerhat.light.green.on()
time.sleep(0.2)
explorerhat.light.green.off()
explorerhat.light.red.on()
time.sleep(0.2)
explorerhat.light.yellow.on()
explorerhat.light.red.off()
time.sleep(0.2)
explorerhat.light.yellow.off()
if pattern = 2:
explorerhat.light.blue.on()
explorerhat.light.red.on()
time.sleep(0.4)
explorerhat.light.yellow.on()
explorerhat.light.green.on()
explorerhat.light.red.off()
explorerhat.light.blue.off()
time.sleep(0.4)
explorerhat.light.green.off()
explorerhat.light.yellow.off()
In this case, explorerhat.touch.pressed is our George. He will watch all of ExplorerHAT’s buttons and call the change_pattern function when one of them is pressed.
change_pattern is super simple, it just sets our pattern variable to the channel ( or button ) number. Press 1 and pattern will be set to 1. Etc!
Now, our while loop is where the magic happens. It doesn’t have to worry about who’s pressing what button anymore, so it can just check what number pattern we should be running and keep running the corresponding pattern.