按钮

EXP Brain 的三个按钮可以访问三个对象：

• buttonCheck

• buttonLeft

• buttonRight

按下()

The pressed(callback, arg) method registers a function to be called when a button is pressed.

参数	描述
打回来	按下按钮时调用的函数。
arg	**可选。**用于向回调函数传递参数的元组。

**返回：**事件类的一个实例。

# Define a function button_pressed().
def button_pressed():
    # The Brain will print that the button was pressed on
    # the Brain's screen.
    brain.screen.print("button pressed")

# Run button_pressed() when the left button is pressed.
brain.buttonLeft.pressed(button_pressed)

发布()

The released(callback, arg) method registers a function to be called when a button is released.

参数	描述
打回来	释放按钮时调用的函数。
arg	**可选。**用于向回调函数传递参数的元组。

**返回：**事件类的一个实例。

# Define a function button_released().
def button_released():
    # The Brain will print that the button was released on
    # the Brain's screen.
    brain.screen.print("button released")

# Run button_released() when the left button is released.
brain.buttonLeft.released(button_released)

紧迫（）

The pressing() method returns whether a button is currently being pressed.

Returns: True if the button is being pressed. False if it is not.