Kivy - Error Unable permissions?

Question

I need some help. I'm studying kivy and I use pycharm as IDE for development. To work with kivy I created a virtualenvs with requeriments:

kivy = 1.10
Cython = 0.23
Python = 3.5

As for setup I did not have too much trouble. It came later when I tried to generate a layout and it did not appear. Is my code:

# coding = utf-8

from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.textinput import TextInput
from kivy.uix.button import Button
from kivy.core.window import Window

def click():
    print (ed.text)

def build():

    layout = FloatLayout()

    ed = TextInput(text="USER.COM")
    global ed
    ed.size_hint = None, None
    ed.height = 300
    ed.width = 400
    ed.y = 60
    ed.x = 250

    bt = Button(text="Click Me")
    bt.size_hint = None, None
    bt.height = 50
    bt.width = 200
    bt.y = 150
    bt.x = 170
    bt.size_hint = None, None
    bt.on_press = click()

    layout.add_widget(ed)
    layout.add_widget(bt)

    return layout


Window.size=600,600
open= App()
open.title = "USER_FREE_AS"
open.buid=build
open.run()

The log reports that pycharm is not allowed to access the function. Is my log:

/home/user/.virtualenvs/k35/bin/python /home/user/Projetos/Python/kivy/source/tela_layout/main.py
/home/user/Projetos/Python/kivy/source/tela_layout/main.py:18: SyntaxWarning: name 'ed' is assigned to before global declaration
  global ed
[INFO   ] [Logger      ] Record log in /home/victorpenna/.kivy/logs/kivy_17-11-13_11.txt
[INFO   ] [Kivy        ] v1.10.0
[INFO   ] [Python      ] v3.5.2 (default, Sep 14 2017, 22:51:06) 
[GCC 5.4.0 20160609]
[INFO   ] [Factory     ] 194 symbols loaded
[INFO   ] [Image       ] Providers: img_tex, img_dds, img_sdl2, img_gif (img_pil, img_ffpyplayer ignored)
[INFO   ] [Text        ] Provider: sdl2
[INFO   ] [OSC         ] using <multiprocessing> for socket
[INFO   ] [Window      ] Provider: sdl2(['window_egl_rpi'] ignored)
[INFO   ] [GL          ] Using the "OpenGL" graphics system
[INFO   ] [GL          ] Backend used <gl>
[INFO   ] [GL          ] OpenGL version <b'3.0 Mesa 17.3.0-rc2 - padoka PPA'>
[INFO   ] [GL          ] OpenGL vendor <b'Intel Open Source Technology Center'>
[INFO   ] [GL          ] OpenGL renderer <b'Mesa DRI Intel(R) HD Graphics 5500 (Broadwell GT2) '>
[INFO   ] [GL          ] OpenGL parsed version: 3, 0
[INFO   ] [GL          ] Shading version <b'1.30'>
[INFO   ] [GL          ] Texture max size <16384>
[INFO   ] [GL          ] Texture max units <32>
[INFO   ] [Window      ] auto add sdl2 input provider
[INFO   ] [Window      ] virtual keyboard not allowed, single mode, not docked
[INFO   ] [ProbeSysfs  ] device match: /dev/input/event8
[INFO   ] [MTD         ] Read event from </dev/input/event8>
[INFO   ] [ProbeSysfs  ] device match: /dev/input/event13
[INFO   ] [MTD         ] Read event from </dev/input/event13>
[INFO   ] [ProbeSysfs  ] device match: /dev/input/event14
[INFO   ] [MTD         ] Read event from </dev/input/event14>
[INFO   ] [Base        ] Start application main loop
[WARNING] [MTD         ] Unable to open device "/dev/input/event8". Please ensure you have the appropriate permissions.
[WARNING] [MTD         ] Unable to open device "/dev/input/event13". Please ensure you have the appropriate permissions.
[WARNING] [MTD         ] Unable to open device "/dev/input/event14". Please ensure you have the appropriate permissions.
[INFO   ] [Base        ] Leaving application in progress...

Process finished with exit code 0

How can I solve this problem?

P.S: My linux is ubuntu 16.04, Intel GPU.

Answer 1

Change owner of event<X> to current user by

sudo chown $whoami:input /dev/input/event8

or run it as root like as

sudo ./env/bin/python3 main.py

Answer 2

Dark Window

A dark window was displayed because there is a typo error.

Replace:

open.buid=build

with:

open.build=build

Kivy Documentation

Programming Guide » Kivy Basics

Programming Guide » Kv language

Device Permission

In order to use these devices, you need to grant the user or group permission. This can be done via (in your case, replace "X" with 8, 13, 14):

$ sudo chmod u+r /dev/input/eventX

SyntaxWarning: name 'ed'

You should declare global variable ed before assignment.

ed = ""


def click():
    print (ed.text)


def build():
    global ed

    layout = FloatLayout()

    ed = TextInput(text="USER.COM")

Output

Answer 3

You have a typo:

open.buid=build

should probably be

open.build=build

But don't do that. Putting methods to an instance afterwards (monkeypatching) gets very confusing fast. Other developers will not expect it in this situation. Also kivy does some magic with the classname of the app, it will locate the .kv file following a naming convention. So instead write:

from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.textinput import TextInput
from kivy.uix.button import Button
from kivy.core.window import Window

class MyApp(App):

    def click(self):
        print(self.ed.text)

    def build(self):

        layout = FloatLayout()

        self.ed = TextInput(text="USER.COM")
        ed.size_hint = None, None
        ed.height = 300
        ed.width = 400
        ed.y = 60
        ed.x = 250

        bt = Button(text="Click Me")
        bt.size_hint = None, None
        bt.height = 50
        bt.width = 200
        bt.y = 150
        bt.x = 170
        bt.size_hint = None, None
        bt.on_press = click()

        layout.add_widget(ed)
        layout.add_widget(bt)

        return layout


Window.size=600,600
open= MyApp()
open.title = "USER_FREE_AS"
open.run()

That way you also avoid the global variable, which is most of the time a sign that you do something suboptimal.

If you are still new to kivy I recommend going through the kivy tutorials.