活动#

介绍#

事件允许您并行运行函数。您无需按顺序调用函数，而是可以将多个函数注册到一个事件中，并一次性触发它们。每个注册的函数都在其自身的线程中运行，从而使您的机器人能够同时执行多个任务——例如在行驶过程中在屏幕上显示数值。

要创建和使用事件，请按以下步骤操作：

  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.

创建活动#

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

Usage:
Event()

范围

描述

此构造函数没有参数。

 
# 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)

将函数注册到事件#

当您将一个函数注册到某个事件时，当该事件被广播时，该函数将在单独的线程中执行。

Usage:
event(callback, args)

范围

描述

event

先前创建的事件对象的名称。

callback

预先定义的函数，将在事件广播时执行。

args

可选。要传递给回调函数的参数元组。

 
# 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()

直播活动#

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()

范围

描述

event

先前创建的事件对象的名称。

 
# 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()

范围

描述

event

先前创建的事件对象的名称。

 
# 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.")
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