expyriment.io.Keyboard

class expyriment.io.Keyboard(default_keys=None)

A class implementing a keyboard input.

Calling expyriment.control.initialize(exp) will automatically create a keyboard instance and will reference it in exp.keyboard for easy access.

__init__(default_keys=None)

Create a keyboard input.

Parameters:

default_keysint or list, optional

a default key or list of default keys

check(keys=None, check_for_keyup=False, check_for_control_keys=True)

Check if keypress is in event queue.

Parameters:

keysint or list, optional

a specific key or list of keys to check

check_for_keyupbool, optional

if True checks for key-up (default = False)

check_for_control_keysbool, optional

checks if control key has been pressed (default = True)

Returns:

keyint

pressed key or None. Only the first occurrence is returned!

Notes

Keys are defined by keyboard constants (please see misc.constants).

When checking for key-down (default), all key-up events are first cleared, and when checking for key-up events, all key-down events are first cleared!

clear()

Clear the event queue from keyboard events.

property default_keys

Getter for default keys

static get_pause_key()

Returns the currently defined pause key

static get_quit_key()

Returns the currently defined quit key

property logging

Getter for logging.

static process_control_keys(key_event=None, quit_confirmed_function=None)

Check if quit_key or pause_key has been pressed.

Reads pygame event cue if no key_event is specified.

Parameters:

key_eventint, optional

key event to check. If not defined, the Pygame event queue will be checked for key down events.

quit_confirmed_functionfunction, optional

function to be called if quitting has been confirmed.

Returns:

outbool

True if quitting or pause screen has been displayed, False otherwise

read_out_buffered_keys()

Reads out all keydown events and clears queue.

set_logging(onoff)

Set logging of this object on or off

Parameters:

onoffbool

set logging on (True) or off (False)

See also

expyriment.design.Experiment.set_log_level

static set_pause_key(value)

Set the currently defined pause key

static set_quit_key(value)

Set the currently defined quit key

wait(keys=None, duration=None, wait_for_keyup=False, callback_function=None, process_control_events=True)

Wait for keypress(es) (optionally for a certain amount of time).

This function will wait for a keypress and returns the found key as well as the reaction time. (This function clears the event queue!)

Parameters:

keysint or list, optional

a specific key or list of keys to wait for

durationint, optional

maximal time to wait in ms

wait_for_keyupbool, optional

if True it waits for key-up (default=False)

callback_functionfunction, optional

function to repeatedly execute during waiting loop

process_control_eventsbool, optional

process io.Keyboard.process_control_keys() and io.Mouse.process_quit_event() (default = True)

Returns:

foundchar

pressed character

rtint

reaction time in ms

See also

expyriment.design.Experiment.register_wait_callback_function

Notes

Keys are defined by keyboard constants (please see misc.constants).

wait_char(char, duration=None, callback_function=None, process_control_events=True)

Wait for character(s) (optionally for a certain amount of time).

This function will wait for one or more characters and returns the found character as well as the reaction time. (This function clears the event queue!)

Parameters:

charint or list

a specific character or list of characters to wait for

durationint, optional

maximal time to wait in ms

callback_functionfunction, optional

function to repeatedly execute during waiting loop

process_control_eventsbool, optional

process io.Keyboard.process_control_keys() and io.Mouse.process_quit_event() (default = True)

Returns:

foundchar

pressed character

rtint

reaction time in ms

See also

expyriment.design.Experiment.register_wait_callback_function