Some questions about switches in python - python

This is my first Question here at StackOverflow, so please be patient with me if some info isn't present or I missed something important, but anyways i'll do my best :)
Recently I started to code in Python2.7, so I'm not very good at it. While playing with PyGtk, PyGObject, Glade, etc I found something particular about switches (Haven't tried with any other widget, so I don't know if it happens somewhere else. Most likely it doesn't, I hope...)
I made a very basic GUI with a single "window" plus a "switch" using Glade
My objective was to deactivate switch after user tried to activate it if some exeption raised up before, something like:
Activate it --> * Found error --> * Deactivate it
I made some code, and after a while, I noted that THIS piece of code created a loop-like block, blocking GUI's window afterwards:
builder = Gtk.Builder()
window1 = builder.get_object('window')
switchie = builder.get_object('switchie')
switchie.set_active(False)
def Hi(switch, active):
print switchie.get_active()
switchie.set_active(not switchie.get_active())
switchie.connect("""notify::active""", Hi)
window1.set_position(Gtk.WindowPosition.CENTER)
window1.connect("delete-event", Gtk.main_quit)
window1.show_all()
If i'm right, "switchie.connect" links "switchie" object with "Hi" func whenever "switchie" gets clicked.
But if I execute this and try to turn switch on, GUI hangs up. I did try to execute this via script & command-line and adding the "print switch state", resulting in an endless loop (True & False)
I tried with many other funcs I made, but neither of them could solve this issue. In fact, this is the "essence" of all the other funcs I made.
Why does this happen?
Where's the loop?
Am I wrong in some line?
Help is appreciated!
(If you need to see the rest of my faulty funcs, just ask for 'em, but I don't think they'll help...)

You want to hook up the switch like this:
switchie.connect("""activate""", Hi)
This will only get called once for every time it is clicked. What you were doing is hooking up to the signal after it changed, so it was constantly changing, and never catching up. You will also want to change
def Hi(switch, active):
to
def Hi(switch, active = None):
for keyboard support.

Related

Python 2.7: Close a dialog without exiting the entire application

I'm running a script coded in python from a scripts menu in a desktop application. It's basically a giant macro that I wrote and added a GUI to. I'm pretty sure the GUI is a really old one that my desktop app uses called dialogKit from MIT.
GitHub still has it here.
The problem is the word "stop" at the very end of the dialog code.
I keep getting a "stop is undefined" message, which I understand, but I've tried everything to close the dialog and if I use exit(), sys.exit(), I don't get an error, but it also closes my entire desktop app.
I need to close the dialog and keep the software open.
The limited dialog documentation for what I'm using can be found here.
(you might have to click on the Dialog section. Their site uses frames.)
class MyDialog:
def __init__(self):
self.d = Dialog(self)
self.d.size = Point(300, 340)
self.d.Center()
self.d.title = "Halftone" #<----- Title of the dialogue
self.d.AddControl(STATICCONTROL, Rect(aIDENT, aIDENT, aIDENT, aIDENT), "frame", STYLE_FRAME)
# more controls and methods..
def on_ok(self, code):
return 1
def on_cancel(self, code):
print "blah"
def Run(self):
return self.d.Run()
d = MyDialog()
if d.Run()!= 1:
stop
I just need a way to change stop to something that 1) will prevent the script from running, and 2) close the dialog without quitting the entire application. This is the functionality of a typical "cancel" button, which is what I want.
Another option is the method called on_cancel(), which I also tried and could get the event itself to work, but still the entire application quits with any kind of exit().
The docs show a method called End(), which claims to terminate the dialog object, but I've tried and failed to get that to work either.
Okay, I'm posting an answer because I think I have a handle on your problem.
Try replacing stop with:
d.d.End()
If that works, you might want to try putting:
self.d.End()
inside of the on_cancel function in your class. That should close the dialogue without closing your program.

Weird behavior - wxPython Events

I have this following piece of code. It is working sometimes, it is not the other time.
def OnReset(self, event):
self.reset_pump.Disable() # Disables the button so it is clicked
self.WriteToController([0x30],'GuiMsgIn') # Sends the reset command
self.flag_read.set()
self.tr.join()
time.sleep(2)
start = time.time()
self.offset_text_control.Clear()
print "Helloin reset"
self.gain_text_control.Clear()
self.firmware_version_text_control.Clear()
self.pump_rpm_text_control.Clear()
self.pressure_text_control.Clear()
self.last_error_text_control.Clear()
self.error_count_text_control.Clear()
self.pump_model_text_control.Clear()
self.pump_serial_number_text_control.Clear()
self.on_time_text_control.Clear()
self.job_on_time_text_control.Clear()
#self.MessageBox('Pump RESET going on Click OK \n')
# Having the above step is useful
print time.time() - start
#self.ser.close()
wx.CallLater(3000, self.CalledAfter, [event,])
def CalledAfter(self, event):
self.tr = threading.Thread(target=ReadData, name="ReadThread", args=(self.ser, self.flag_read))
self.tr.daemon = True
self.tr.start()
self.reset_pump.Enable()
What it does is When I click the Reset button on my GUI, it has to clear certain text fields on the GUI. It has to clear it, only after joining the self.tr thread.
Once it clears, it will execute the command wx.CallLater(3000, self.CalledAfter, [event,]). Which then starts a new thread again.
Apparently The .Clear() command is working very at a non consistent level, it is working some time, not working the other times, and working again.
Any idea why this might happen would be very helpful.
There seems to be a difference in the way SetValue and Clear update the windows. Calling SetValue("") seems to be a suitable workaround to this behavior.

What is causing this cascade menu failure with tkinter in python?

The following code exhibits a problem I do not understand:
from Tkinter import *
root = Tk()
cheese_var = IntVar()
parrot_var = IntVar(value=1)
check_menu = Menu(tearoff=0)
check_menu.add_checkbutton(label="Cheese", variable=cheese_var)
check_menu.add_checkbutton(label="Parrot", variable=parrot_var)
count = 0
class Top():
def __init__(self):
global count
count += 1
self.tl = Toplevel(root)
Label(self.tl, text="Window " + str(count)).pack()
self.mb = Menubutton(self.tl, text="Push Me", bg='pink')
self.menu = Menu(self.mb, tearoff=0)
self.menu.add_cascade(label="Choices", menu=check_menu)
self.menu.add_command(label="New Window", command=new_top)
self.mb.config(menu=self.menu)
self.mb.pack()
def new_top():
Top()
Top()
root.mainloop()
The menu brought up by the menu button in the created top level window initially behaves as expected. Clicking on the New Window command there creates a new such window, which also behaves as expected. Indeed, as long as you keep creating new top level windows, everything continues to work as expected. However, once you delete (close) any one of those windows, then, in a subsequently created new window, the Choices cascade on the new menu is not functional. (It is still OK in the windows created before the closing of one.)
The situation in which I initially encountered this symptom was much more complex, but I was able to simplify it down to the above example which exhibits the issue. I have discovered that I can avoid the problem by having each instance of Top create its own check_menu as an attribute; but I do not understand why this should be necessary. Please point me the way if there is one to avoid the problem without such replication of a cascade menu used in multiple windows.
Unfortunately, I don't think it is possible to do what you want. I'll try to explain as best as I can.
When you first run the script, check_menu is created and works fine for the first window. As you create more windows, check_menu is simply shared between them. However, when you close one of them, check_menu (and everything under it) is destroyed. So, when you create a new window after that, check_menu no longer exists and it doesn't show.
However, the script doesn't throw an error because, for some reason, Tkinter allows you to assign menus to things that aren't menus. Believe it or not, none of the following code:
self.menu.add_cascade(label="Choices", menu=None)
self.menu.add_cascade(label="Choices", menu=1)
self.menu.add_cascade(label="Choices", menu="")
will break the script. Each line simply does nothing but create an empty cascade "Choices".
That is basically what is happening. After closing one window, check_menu and everything under it is destroyed. Yet, Tkinter doesn't throw an error but instead assigns a menu to something that is no longer a menu (as far as what it is assigning the menu to, I believe it is using the old instance of check_menu, which was destroyed).
To solve this problem, recreate check_menu and everything under it each time you call Top. In other words, put the code for check_menu (and its options) in the __init__ method of Top. That way, each time Top is called, check_menu will exist.
Hope this helps (and that I explained it sufficiently :)

Python Roguelike: Inventory Disappears

Today I progressed further into this Python roguelike tutorial, and got to the inventory. As of now, I can pick up items and use them. The only problem is, when accessing the inventory, it's only visible for a split second, even though I used the console_wait_for_keypress(True) function. I'm not sure as to why it disappears. Here's the code that displays a menu(in this case, the inventory):
def menu(header,options,width):
if len(options)>26: raise ValueError('Cannot have a menu with more than 26 options.')
header_height=libtcod.console_get_height_rect(con,0,0,width,SCREEN_HEIGHT,header)
height=len(options)+header_height
window=libtcod.console_new(width,height)
libtcod.console_set_default_foreground(window,libtcod.white)
libtcod.console_print_rect_ex(window,0,0,width,height,libtcod.BKGND_NONE,libtcod.LEFT,header)
y=header_height
letter_index=ord('a')
for option_text in options:
text='('+chr(letter_index)+')'+option_text
libtcod.console_print_ex(window,0,y,libtcod.BKGND_NONE,libtcod.LEFT,text)
y+=1
letter_index+=1
x=SCREEN_WIDTH/2-width/2
y=SCREEN_HEIGHT/2-height/2
libtcod.console_blit(window,0,0,width,height,0,x,y,1.0,0.7)
libtcod.console_flush()
key=libtcod.console_wait_for_keypress(True)
index=key.c-ord('a')
if index>=0 and index<len(options): return index
return None
I'd appreciate anyone's help or input to this problem.
It may be related to an old version of the library that has an event when you press a key, and another event when you release it. So this could cause it to appear and disappear when you release the key.
So try to see if the screen stays on if you keep the key pressed.
wait_for_keypress does indeed trigger on both press and release events. To fix this, replace wait_for_keypress with the sys_wait_for_event, specifying to trigger only on press events.
Documentation

How to stop a warning dialog from halting execution of a Python program that's controlling it?

Using Win32GUI and Watsup, I'm writing a bit of Python code to automate a search across a database that is accessed through a program that doesn't come with an interface for it. As such, I can take a string from a list and then input it into the search box and press 'lookup'.
However, when the search returns more than 1000 results, the program throws a warning dialog --which is simply a notification of the number of results--which halts the execution of the Python code. I can't get the code to progress past the line where it presses lookup.
At a guess, this would be because it doesn't expect a window or know how to handle a warning--but I don't either, other than manually accepting it. Below is the relevent sample of code, though it's probably not very enlightening. After "clickButton(LookupButton)", the execution halts.
LookupButtonlocation = elemstring.find("Lookup", AuthNameFieldlocation) - 15
#Use Regex search to find handles
number_regex = re.compile(';(\d+);')
AuthNameEdit = int(number_regex.search(elemstring[AuthNameFieldlocation:]).group(1))
LookupButton = int(number_regex.search(elemstring[LookupButtonlocation:]).group(1))
#Input new Author into Edit Field
setEditText(AuthNameEdit, "John Campbell")
#Click lookup button
clickButton(LookupButton)
I'm not a WATSUP user, but I do something very similar using pywinauto - in my case I'm running a number of automated tests that open various 3rd party programs that, in a similar way, throw up inconvenient warning dialogs. It's a bit difficult to deal with dialogs that you don't know about, however if you do know which dialogs appear, but not when they appear, you can start a thread to just deal with those pop-ups. The following is a simple example from what I'm doing, and uses pywinauto but you could adapt the approach for WATSUP:
import time
import threading
class ClearPopupThread(threading.Thread):
def __init__(self, window_name, button_name, quit_event):
threading.Thread.__init__(self)
self.quit_event = quit_event
self.window_name = window_name
self.button_name = button_name
def run(self):
from pywinauto import application, findwindows
while True:
try:
handles = findwindows.find_windows(title=self.window_name)
except findwindows.WindowNotFoundError:
pass #Just do nothing if the pop-up dialog was not found
else: #The window was found, so click the button
for hwnd in handles:
app = application.Application()
app.Connect(handle=hwnd)
popup = app[self.window_name]
button = getattr(popup, self.button_name)
button.Click()
if self.quit_event.is_set():
break
time.sleep(1) #should help reduce cpu load a little for this thread
Essentially this thread is just an infinite loop that looks for a pop-up window by name, and if it finds it, it clicks on a button to close the window. If you have many pop-up windows you can open one thread per popup (bug that's not overly efficient, though). Because it's an infinite loop, I have the thread looking to see if an event is set, to allow me to stop the thread from my main program. So, in the main program I do something like this:
#Start the thread
quit_event = threading.Event()
mythread = ClearPopupThread('Window Popup Title', 'Yes button', quit_event)
# ...
# My program does it's thing here
# ...
# When my program is done I need to end the thread
quit_event.set()
This is not necessarily the only way to deal with your issue, but is a way that's worked for me. Sorry I can't really help you much with dealing with WATSUP (I always found pywinauto a bit easier to use), but I noticed on the WATSUP homepage (http://www.tizmoi.net/watsup/intro.html), Example 2 does something similar without using threads, i.e., looks for a named window and clicks a specific button on that window.

Categories

Resources