Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Supported by

Use Expyriment script on Android devices

I would like use simple Scripts, made with Expyriment, for visual stimuli presentations and answer collections on a samsung galaxy Tab S2 (android 7.0). But I have problems when I try to run them. The example experiments "line-bisection.py" works correctly but if I only add the drawing of a circle or the use of circular (instead of rectangular) keys the program no longer works. Can you tell me what is the problem or what I wrong? There are limitations on the Python/Expyriment commands that are recognized during the execution of experiments in android. Thank you.

Comments

  • Very difficult to say without knowing your code, sorry.

  • This is the code:

    I wrote in bold the changes to the original program "line-bisection.py"

    Thanks you

    very much


    #!/usr/bin/env python

    # -*- coding: utf-8 -*-


    """

    A line bisection task.

    This example is appropriate to illustrates the use of the Android runtime environment for Exypriment on tablet PC.

    """

    from __future__ import division


    from expyriment import control, stimuli, io, design, misc


    # settings

    design.defaults.experiment_background_colour = misc.constants.C_GREY

    design.defaults.experiment_foreground_colour = misc.constants.C_BLACK

    line_length = 200


    def line_bisection_task(line_length, position):

      # make button

      button = stimuli.Rectangle(size=(40,20),

            position=(exp.screen.size[0]//2-25, 15-exp.screen.size[1]//2))

      button_text = stimuli.TextLine(text="ok", position=button.position, text_colour=misc.constants.C_WHITE)

      mark_position = None

      while True:

        canvas = stimuli.BlankScreen()

        line = stimuli.Rectangle(size=(line_length,3), position=position,

              colour=misc.constants.C_BLACK)

        line.plot(canvas)

        if mark_position is not None:

          # plot button and mark line on canvas

          button.plot(canvas)

          button_text.plot(canvas)

          markline = stimuli.Rectangle(size=(1,25),

                position=(mark_position, line.position[1]),

                colour=misc.constants.C_RED)

          markline.plot(canvas)

        # present stimulus

        canvas.present()

        # wait for mouse or touch screen response

        _id, pos, _rt = exp.mouse.wait_press()

        # process clicked position position

        if abs(pos[1]-line.position[1])<=50 and\

              abs(pos[0]-line.position[0])<=line_length//2:

          mark_position = pos[0]

        else:

          if button.overlapping_with_position(pos): # is button pressed

            return mark_position - line.position[0]


    ### init ###

    exp = control.initialize()


    # create touch button box

    buttonA = stimuli.Circle(radius= 20, position=(-60, 0))

    buttonB = stimuli.Circle(radius= 20, position=(60, 0))

    textA = stimuli.TextLine(text="quit", position=buttonA.position, text_colour=misc.constants.C_WHITE)

    textB = stimuli.TextLine(text="next", position=buttonB.position, text_colour=misc.constants.C_WHITE)

    touchButtonBox = io.TouchScreenButtonBox(button_fields=[buttonA, buttonB], stimuli=[textA, textB])

    ### start ###

    control.start(exp)

    exp.mouse.show_cursor()


    # trial loop

    while True:

      # find random position

      rx, ry = ((exp.screen.size[0]-line_length)//2, (exp.screen.size[1]-50)//2)

      pos = [design.randomize.rand_int(-rx, rx), design.randomize.rand_int(-ry, ry)]

      # present task

      judgment = line_bisection_task(line_length, position=pos)

      # save data

      exp.data.add(pos +[judgment])

      # ask for new trail

      touchButtonBox.show()

      btn, _rt = touchButtonBox.wait()

      if btn==buttonA:

        break


    ## end##

    control.end()

  • The Android Runtime is currently still based on Expyriment 0.7.0. The Circle stimulus in this release does not have a parameter called "radius", but one called "diameter".

  • I have installed experiment 0.7.0 on my PC and modified the program. Now it works correctly on the PC and on the tablet.

    Thanks you very much

Sign In or Register to comment.