simple tkinter battery monitor

[leonix.power]

I tried to write a simple battery monitor for laptops which shows normally just the battery percentage, and when is clicked some more info.
If I click just one time it works, but if I click a second time, the additional info Label seems to be empty (but it holds the dimension of the StringVar content, even if it isn't displayed)
Where am I wrong?
---------------------------------------------------
#!/usr/bin/python3.2

from re import findall, search
from threading import Thread
from time import sleep
from subprocess import Popen, call, PIPE, STDOUT
from tkinter import *



class battery_monitor:

def __init__(self):
root=Tk()
# root.geometry("-0+0")
root.overrideredirect(True)
root.wm_attributes("-topmost", 1)
self.battery_string=StringVar()
self.battery_percent=StringVar()
self.battery_label=Label(root, extvariable=self.battery_string, font=("fixed", 9))
self.battery_icon=Label(root, textvariable=self.battery_percent, font=("fixed", 9), width=3)
self.battery_icon.grid()
t=Thread(target=self.update_battery_level_loop)
t.start()
root.bind("<Button-1>", self.display_details)
self.root=root
root.mainloop()

# displays a message about details of battery status
# i.e. "on-line" or "charging, 20 min left" and so on
def display_details(self, event):
self.battery_icon.grid_remove()
self.battery_label.grid()
self.root.update_idletasks()
sleep(1)
self.battery_label.grid_remove()
self.battery_icon.grid()
self.root.update_idletasks()

# dummy function used just to test the GUI
def read_battery_level(self):
self.level=100
return "battery is full"

# threaded function, should constantly update the battery level
def update_battery_level_loop(self):
self.read_battery_level()
while True:
self.battery_percent.set(self.level)
self.battery_string.set(self.read_battery_level())
sleep(5)





##############################################
#
# main

battery_monitor()

 

[Dave Angel]

I tried to write a simple battery monitor for laptops which shows normally just the battery percentage, and when is clicked some more info.
If I click just one time it works, but if I click a second time, the additional info Label seems to be empty (but it holds the dimension of the StringVar content, even if it isn't displayed)
Where am I wrong?

See inline comment.

---------------------------------------------------
#!/usr/bin/python3.2

from re import findall, search
from threading import Thread
from time import sleep
from subprocess import Popen, call, PIPE, STDOUT
from tkinter import *



class battery_monitor:

def __init__(self):
root=Tk()
# root.geometry("-0+0")
root.overrideredirect(True)
root.wm_attributes("-topmost", 1)
self.battery_string=StringVar()
self.battery_percent=StringVar()
self.battery_label=Label(root, extvariable=self.battery_string, font=("fixed", 9))

I don't know tkinter very well, and I don't have 3.2, but the keyword
seems to be wrong. Don't you want textvariable= ??

self.battery_icon=Label(root, textvariable=self.battery_percent, font=("fixed", 9), width=3)
self.battery_icon.grid()
t=Thread(target=self.update_battery_level_loop)
t.start()
root.bind("<Button-1>", self.display_details)
self.root=root
root.mainloop()

# displays a message about details of battery status
# i.e. "on-line" or "charging, 20 min left" and so on
def display_details(self, event):
self.battery_icon.grid_remove()
self.battery_label.grid()
self.root.update_idletasks()
sleep(1)

Never use sleep() inside a gui's main thread. There are other ways to
delay the UI without locking it up.

self.battery_label.grid_remove()
self.battery_icon.grid()
self.root.update_idletasks()

# dummy function used just to test the GUI
def read_battery_level(self):
self.level=100
return "battery is full"

# threaded function, should constantly update the battery level
def update_battery_level_loop(self):
self.read_battery_level()
while True:
self.battery_percent.set(self.level)
self.battery_string.set(self.read_battery_level())
sleep(5)

This sleep() is okay.

 

[Rick Johnson]

I tried to write a simple battery monitor for laptops
which shows normally just the battery percentage, and when
is clicked some more info.

If I click just one time it works, but if I click a second
time, the additional info Label seems to be empty (but it
holds the dimension of the StringVar content, even if it
isn't displayed)

Where am I wrong?

Before i discover your code logic error, i want to expose style errors.

---------------------------------------------------
#!/usr/bin/python3.2

from re import findall, search
from threading import Thread
from time import sleep
from subprocess import Popen, call, PIPE, STDOUT
from tkinter import *

I am wondering why you would "selectively" import from the re module, which is a quite normal sized module, but then do the global import from tkinter, of which who's namespace is terribly polluted due to lack of packaging.

class battery_monitor:

Bad naming convention here! ALL class identifiers must (at the very least) /start/ with a capital letter. My strong opinion is to cap EVERY word. So for example:

OptionMenu NOT Optionmenu
ComboBox NOT Combobox
etc...

Using "lowercase_with_underscores" should be reserved for interface methods and global functions.

def __init__(self):
root=Tk()
# root.geometry("-0+0")
root.overrideredirect(True)
root.wm_attributes("-topmost", 1)

I just hate when people use 1 and 0 for True and False. I know Python allows such non-sense, but i just hate it because it can cause subtle bugs -- and most logical people agree with me.

self.battery_string=StringVar()
self.battery_percent=StringVar()

Two issues here. First you use a function/interface style to define a variable. Then you go and add insult to injury by using an ambiguous name. You should have used something like: "batteryStringVar" and "batteryPercentVar".

self.battery_label=Label(root, extvariable=self.battery_string, font=("fixed", 9))
self.battery_icon=Label(root, textvariable=self.battery_percent, font=("fixed", 9), width=3)
self.battery_icon.grid()
t=Thread(target=self.update_battery_level_loop)

Don't assign variables without leaving buffer spaces around the equals sign. Only omit the spaces when passing arguments to a class, method, or function.

t.start()
root.bind("<Button-1>", self.display_details)
self.root=root
root.mainloop()

# displays a message about details of battery status
# i.e. "on-line" or "charging, 20 min left" and so on

Oh gawd this is a major pet peeve of mine!!!!

Always place a comment at the same indention level of the function or class that it references. AND NEVER, EVER, place a comment OUTSIDE of a function, method, or class like you have done here.

def display_details(self, event):
self.battery_icon.grid_remove()
self.battery_label.grid()
self.root.update_idletasks()
sleep(1)

You may want to look into the Universal Tkinter widget method: "w.after(ms, func)".

self.battery_label.grid_remove()
self.battery_icon.grid()
self.root.update_idletasks()

# dummy function used just to test the GUI
def read_battery_level(self):
self.level=100
return "battery is full"

# threaded function, should constantly update the battery level
def update_battery_level_loop(self):
self.read_battery_level()
while True:
self.battery_percent.set(self.level)
self.battery_string.set(self.read_battery_level())
sleep(5)

Finally, i don't understand why you are using such a deep indention level. Unknown Source said: "Four spaces thou shalt indent, and the number of thou indention shall be four."

Only after you clean up these style abominations by submitting a new example of your code will i offer any more help. Thanks.

 

[leonix.power]

Thank you very much! fixed with w.after
Here is the code, works under Linux for those who have acpi.
My output of "acpi -V" is the following, the code is parsing the first line of the output. Any improvements are appreciated.

$ acpi -V
Battery 0: Discharging, 12%, 00:10:59 remaining
Battery 0: design capacity 2200 mAh, last full capacity 1349 mAh = 61%
Adapter 0: off-line
Thermal 0: ok, 40.0 degrees C
Thermal 0: trip point 0 switches to mode critical at temperature 98.0 degrees C
Thermal 0: trip point 1 switches to mode passive at temperature 93.0 degrees C
Cooling 0: Processor 0 of 10
Cooling 1: Processor 0 of 10
Cooling 2: Processor 0 of 10
Cooling 3: Processor 0 of 10
Cooling 4: LCD 0 of 9

----------------------------------------------------------
----------------------------------------------------------
----------------------------------------------------------


#!/usr/bin/python3.2

from re import findall, search
from threading import Thread
from time import sleep
from subprocess import Popen, call, PIPE, STDOUT
from tkinter import Tk, Label, StringVar



def runProcess(exe):
p=Popen(exe, stdout=PIPE, stderr=STDOUT)
while True:
retcode=p.poll()
line=p.stdout.readline()
yield line
if retcode is not None:
break


class BatteryMonitor:

def __init__(self):
root = Tk()
root.configure(padx=1, pady=1, bg="#555753")
root.geometry("-0+0")
root.overrideredirect(True)
root.wm_attributes("-topmost", True)
self.batteryExtendedStringVar = StringVar()
self.batteryPercentStringVar = StringVar()
self.batteryExtendedLabel = Label(root, textvariable=self.batteryExtendedStringVar, font=("fixed", 9), bg="#3e4446", fg="#d3d7cf", padx=10, pady=-1)
self.batteryPercentLabel = Label(root, textvariable=self.batteryPercentStringVar, font=("fixed", 9), width=4, bg="#3e4446", fg="#d3d7cf", padx=-1, pady=-1)
self.batteryPercentLabel.grid()
t = Thread(target=self.update_battery_level_loop)
t.start()
root.bind("<Button-1>", self.display_details)
self.root = root
root.mainloop()

def display_details(self, event):
# displays a message about details of battery status
# i.e. "on-line" or "charging, 20 min left" and so on
self.batteryPercentLabel.grid_remove()
self.batteryExtendedLabel.grid()
self.batteryExtendedLabel.after(1000, self.batteryExtendedLabel.grid_remove)
self.batteryPercentLabel.after(1000, self.batteryPercentLabel.grid)

def read_battery_level(self):
# dummy function used just to test the GUI
for line in runProcess(["acpi", "-V"]):
if line[11:-1]!=b"on-line":
self.level = findall(b"\d\d?", line[11:])[0]
else:
self.level = b"0"
return line[11:-1]

def update_battery_level_loop(self):
# threaded function, should constantly update the battery level
self.read_battery_level()
while True:
self.batteryPercentStringVar.set(str(self.level)[2:-1]+"%")
self.batteryExtendedStringVar.set(self.read_battery_level())
if self.level == 2:
runProcess(["shutdown", "-h", "now"])
return
sleep(5)





##############################################
#
# main

BatteryMonitor()