kmk_firmware/docs/lock_status.md

# Lock Status
This extension exposes host-side locks like caps or num lock.

## Enabling the extension
```python
from kmk.extensions.lock_status import LockStatus

locks = LockStatus()
keyboard.extensions.append(locks)

```

## Read Lock Status
Lock states can be retrieved with getter methods and are truth valued -- `True`
when the lock is enabled and `False` otherwise.

|Method                    |Description |
|--------------------------|------------|
|`locks.get_num_lock() `   |Num Lock    |
|`locks.get_caps_lock() `  |Caps Lock   |
|`locks.get_scroll_lock() `|Scroll Lock |
|`locks.get_compose() `    |Compose     |
|`locks.get_kana() `       |Kana        |


## React to Lock Status Changes
The best way to react to changes in lock status is to extend
the LockStatus class. When a lock status change happens,
the 'after_hid_send' function is envoked so you would override
LockStatus's to inject your own logic. Be aware though that
this function is also critically important to the functionality
of LockStatus so be sure to invoke the 'super()' version of your
class to trigger the default functionality of LockStatus.

```python
# in your main.py
from kb import KMKKeyboard
from kmk.extensions.lock_status import LockStatus
from kmk.extensions.LED import LED

keyboard = KMKKeyboard()
leds = LED(led_pin=[board.GP27, board.GP28])

class LEDLockStatus(LockStatus):
    def set_lock_leds(self):
        if self.get_caps_lock():
            leds.set_brightness(50, leds=[0])
        else:
            leds.set_brightness(0, leds=[0])

        if self.get_scroll_lock():
            leds.set_brightness(50, leds=[1])
        else:
            leds.set_brightness(0, leds=[1])

    def after_hid_send(self, sandbox):
        super().after_hid_send()  # Critically important. Do not forget
        self.set_lock_leds()

keyboard.extensions.append(leds)
keyboard.extensions.append(LEDLockStatus())
```