Eventos

Introducción

Los eventos permiten ejecutar funciones en paralelo. En lugar de llamarlas secuencialmente, puedes registrar varias funciones en un evento y activarlas todas a la vez. Cada función registrada se ejecuta en su propio hilo, lo que permite que tu robot realice varias tareas simultáneamente, como mostrar valores en la pantalla mientras se desplaza.

Para crear y luego usar un evento, siga estos pasos en orden:

1. Create the event with Event.

2. Register a function to trigger when the Event is broadcast by calling the event object with the function as an argument.

3. Broadcast an Event:

   • broadcast — Triggers all registered functions in an event object to run concurrently.

   • broadcast_and_wait — Triggers all registered functions in an event object and waits for them to finish before continuing.

Crear un evento

Event creates an event object that manages function execution in separate threads.

Usage:
Event()

Parámetro	Descripción
	Este constructor no tiene parámetros.

# Blink the screen while moving forward
# Create move_event as an Event object
move_event = Event()

def blink_screen():
    while True:
        brain.screen.clear_screen(Color.RED)
        wait(0.5, SECONDS)
        brain.screen.clear_screen()
        wait(0.5, SECONDS)

move_event(blink_screen)
move_event.broadcast()
drivetrain.drive(FORWARD)

Registrar funciones en un evento

Cuando se registra una función en un evento, esta se ejecutará en un hilo independiente cuando se transmita dicho evento.

Usage:
event(callback, args)

Parámetro	Descripción
event	El nombre del objeto de evento creado previamente.
callback	Una función definida previamente que se ejecutará cuando se transmita el evento.
args	Opcional. Una tupla de argumentos para pasar a la función de devolución de llamada.

# Blink the screen while turning
move_event = Event()

def blink_screen():
    while True:
        brain.screen.clear_screen(Color.RED)
        wait(0.5, SECONDS)
        brain.screen.clear_screen()
        wait(0.5, SECONDS)

def turning():
    drivetrain.turn(RIGHT)

# Register multiple functions to the Event object
move_event(blink_screen)
move_event(turning)

move_event.broadcast()

# Move in a specified direction
move_event = Event()

def move_distance(movement_angle):
    drivetrain.turn_for(RIGHT, movement_angle, DEGREES)
    drivetrain.drive_for(FORWARD, 100, MM)

# Change the parameter to modify how the robot moves
move_event(move_distance, (180,))
move_event.broadcast()

Transmitir un evento

broadcast

broadcast triggers an event, starting all registered functions in separate threads. This method does not pause execution of any subsequent functions.

Usage:
event.broadcast()

Parámetro	Descripción
event	El nombre del objeto de evento creado previamente.

# Blink the screen while moving forward
# Create move_event as an Event object
move_event = Event()

def blink_screen():
    while True:
        brain.screen.clear_screen(Color.RED)
        wait(0.5, SECONDS)
        brain.screen.clear_screen()
        wait(0.5, SECONDS)

move_event(blink_screen)
move_event.broadcast()
drivetrain.drive(FORWARD)

broadcast_and_wait

broadcast_and_wait starts an event but waits for all registered functions to finish before continuing with subsequent functions.

Usage:
event.broadcast_and_wait()

Parámetro	Descripción
event	El nombre del objeto de evento creado previamente.

# Move after the screen is pressed
move_event = Event()

def move_and_turn():
    drivetrain.drive_for(FORWARD, 150, MM)
    drivetrain.turn_for(RIGHT, 90)

move_event(move_and_turn)

while True:
    if brain.buttonCheck.pressing():
        move_event.broadcast_and_wait()
        break
brain.screen.print("Movement done.")