Window moving behind other open windows when button pressed (Python with Tkinter) - python

Apologies if this is a completely easy fix and I've just missed it. I am learning Python and I am trying to develop a GUI alongside my backend code using Tkinter. This is completely foreign to me and I have recently come across the problem that when I press my buttons there is a very small chance that it will make my window move behind all other open programs.
I am not entirely sure what is causing this but my guess is it stems somehow from one of two functions I have; one meant to minimise the main root window and the second to reveal it. However, these functions are not called in any place in my program that I would not expect them and the windows being minimised are not the root window (which my two functions act on).
I have both functions added below (hopefully, I am pretty new to SO) but if any additional code is needed I will supply it. I have quite a bit of code and everything else functions perfectly so I didn't want to post all my code is all.
There is no particular combination of button presses or buttons in particular which cause it, it appears to be any of them seemingly at random. It sends whatever window I have up to the taskbar.
def revealMenu():
root.update()
root.deiconify()
def hideMenu():
root.withdraw()

Related

Function running only after tkinter windows has been closed

I'm learning how to program in Python and use the PIL (Pillow) in order to create small bots which can recognize changes in the screen in order to execute repetitive commands (keyboard presses with pynput module).
I did a small GUI with Tkinter in order to get user information regarding the parameters which the user is going to use (Entry widgets) at their use of the bot and I also need a few buttons for enabling/disabling certain parts of the code (i'm using check buttons and using boolean logic in order to enable/disable) and also for enabling the main function of the bot (which is to press a button once it recognizes a certain change at the screen).
What I am currently experiencing is that the once I run my program, it opens up my GUI and all that a user would see but it doesn't execute my main function, it only executes the main function AFTER I close the GUI.
I'd love to post my code but it exceeds 220 lines and it would probably become even more confusing.
So, long story short, is it a kind of error which happens a lot when inexperienced programmers try to create softwares with tkinter? If yes, what causes it and how can it be fixed?
I appreciate any help you guys can get me. :]
...creates frames, widgets, entries...
mainHealerVar = IntVar()
main_healer_check = Checkbutton(root, text="Enable the bot", variable=mainHealerVar) #this should mean that when i press this checkbutton it'll enable the bot and perform the repetitive commands for as long as it stays checked
... some more buttons/code...
root.mainloop() #right after I stop setting up the GUI, I place this function
... make logic in order to know which part of the repetitive functions to execute...
if mainHealerVar.get() == 1:
mainHealFunction() #function to check if the checkbutton is still pressed (if it is, it should execute mainHealFunction()
It was supposed to execute the repetitive commands by the pynput module as soon as i clicked on the enabling Check-button, but it doesn't execute anything until I close the GUI, then it starts to execute the repetitive commands. I have also tried using a while loop instead of an "if" at the end, but ended up with the same result.

The proper way to display multiple windows in tkinter?

I am currently working on a project using Python and tkinter.
The problem is that I don't know what's the proper way to display multiple windows, or screens, I don't know how to call them. Let me explain better.
When the application starts the login screen appears. After that, if I click register, I want to go to the register screen, but I don't want it to be a separate window (I don't want to have 2 windows displayed at the same time), but rather another window with different content ?!
How should I handle properly this situation? Create a second window using Toplevel and hiding the first (can I do that?) or changing the widgets of the first?
Code I've written so far
You can do that- just call window.withdraw() on the Toplevel you need to hide after creating a new Toplevel. Changing the widgets in the first is also an option- if you like, you could always try a Notebook widget and disable manual flipping or just put each "screen" in a frame and grid_ or pack_forget them to remove them from the window.

Mitigating the misbehaviour of the non-client portion of an application window

I have a program that has some rather bad window handling. I can provide scripting to the client portion of the application but have no control over the non-client portion, apart from some simple movement/resizing commands (that don't help).
The main problem is that when the windows "maximize" button is pressed the WS_MAXIMIZE style is not set. The window is positioned correctly, and helpfully respects the taskbar settings but the application icon/title and "windows buttons" are misplaced and the borders show up on any other screens.
Using winspy++ I was able to set the WS_MAXIMIZE style fixing these graphical annoyances. but this also led into a secondary issue. The "restore" button also does nothing, when pressed it simply reverts the style and does not take the application back to it's pre-maximized position and size.
I was going to make a launcher for this program in Python anyway, to handle some .ini stuff and alterable executable parameters.
I would like to extend this launcher to silently run behind the application, fixing these issues.
These things were intended to be handled by the operating system and the developers of the application do not seem to be focused on working on these problems, but more on increasing the library of application scripting and porting to other systems.
My assumption is that when the launcher is commanded to run the program it needs to have access to the thread/process so that it can poll the position and size of the application window and set the appropriate style when it is required, and more importantly (I guess), have access to it's memory.
Example: [-8,-8] to [1374,776] on a 1366x768 screen with a minimized taskbar.
If there is an asynchronous method to detect when the window has been moved/resized/windows buttons pressed, that would be preferable to polling every step.
Supplying the window with "restore" information to make use of the restore button seems a bit less trivial. I have been reading as much reference as I can find but have not found anything on this. Where is this memory stored? How do I access it? Is it read-only, and only set by the OS?
I'm new to Python, and SO, so I apologize if my question doesn't fit here, I've tried.

Make a window top priority

I have a root window with a panel on it. Then there is this function, in which I create a TopLevel (another window) for asking input from user. I'm trying to find some way to make it compulsory for user to either enter input and click OK or cancel to dismiss the window before being able to access the root window. It's like when an error message pops up, you can't just ignore it and do other things in the root window. Does anyone have any suggestion for me?
Have a look at Dialog Windows. You can use widget.wait_window(window) to achieve this.
You can do what is called a grab, which forces all events into the window of your choice. There are several methods for managing grab, including grab_set and grab_release.
For an example, see NiceGrab.
When working with grabs, exercise extreme care. It's possible to lock up your computer if you do a global grab and then have a bug that prevents you from releasing it. During development I will often implement a timer that kills the program after a minute or so, so if I lock everything up it will be automatically released after a short wait.

Read Only Text widget in python3-tkinter; cross platform

How to suppress end user ability to edit/add/delete text in a Text widget? (Python v3.2.. and tkinter)
The point is to suppress only the ability to change/add/delete text but not to castrate other features. Perhaps a NoEdit Text widged would be a better name.
I've tried .text['state'] = 'disabled' and it works almost OK in Windows (it still allows user to select/copy text highlights the selection, page up/down and up/down buttons work. The only thing broken seems to be the cursor made invisible.)
But on MacIntosh everything is broken. No highlights, no select/copy,... UGH
Since Tkinter has practically no documentation in Python, I've searched and found some TCL advise, to derive a new class and suppress the insert and delete functions.
So, I've tried as so:
class roText(tk.Text):
def insert(self,*args,**kwargs):
print(" Hey - Im inside roText.insert")
pass
def delete(self,*args,**twargs):
pass
def pInsert(self,*args,**twargs):
super().insert(*args,**twargs)
Unfortunately it didn't work right. Apparently tkinter does not use those insert and delete functions when end user enters/deletes code. Perhaps those TCL insert/delete are something else, and I lost something in translation from TCL and Swahili. What functions does tkinter.Text use for end user editing text? Hopefully they are not internal...
So, is there a way to modify the Text widget to suppress only end user editing?
Is there a way to do it without diving inside and overriding internal Tkinter code, so the stuff doesn't get broken by next releases of Tkinter?
Looking at the Idle shell window, I see that they've managed to suppress edits (except for the last line). So there is a way. But what is it and how costly?
Sorry for bumping an old question, but I was searching for an answer to this question also and finally found a solution. The solution I found involves overriding the key bindings when the text widget has focus and is pretty simple. Found here.
To override the bindings of a widget there is a bind function where you pass a string of what is to be overridden and the new function you want it to call.
self.txtBox.bind("<Key>", self.empty)
Somewhere else in the class you'll need to define the function to handle the event.
def empty(self, event):
return "break"
By returning the string "break" the event handler knows to stop after your function, instead of continuing with the default action.
I hope this answers your question. Cheers.
The reason the disabled state doesn't seem to work on the Mac is because it turns off the binding that gives focus to the widget. Without focus, the highlighting on a Mac doesn't show up. If you set the state to disabled but then assign a binding to <ButtonPress-1> to explicitly set focus to the disabled text widget, you can then select and copy text and the highlighting will show.
As for the cursor disappearing... arguably, that's what's supposed to happen. The cursor tells the user "this is where text will get inserted". Since no text will get inserted, having that visual clue would be confusing to the user. What you could do instead, if it was really important, is to insert a small image wherever they click to simulate the cursor.
To answer your question about whether the widget actually uses the insert and delete methods: the methods on the actual underlying widget are what the default bindings use, so overriding them in a subclass has no effect. You would need to redo all the default bindings for that to work. It's doable, but a lot of work.
Unfortunately, this is one area where programming in Tcl really shines, because you can simply disable the insert and delete commands of the widget. Of course, you can do that directly in Tkinter also since ultimately it runs tcl code to do everything, but that would involve writing some tcl code which is not a very good solution from the perspective of a Python coder.
I think the best solution is to use the disabled state, then add in just enough bindings to do what you want.
Here's a simple example that works by explicitly setting focus on a mouse button click. With this code I'm able to click and swipe to select a region, or double- or triple-click to select words and lines:
import Tkinter as tk
class SampleApp(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.text = tk.Text(width=40, height=20)
self.text.bind("<1>", self.set_focus)
self.text.insert("end", "\n".join(dir(tk.Tk)))
self.text.configure(state="disabled")
self.text.pack(fill="both", expand=True)
def set_focus(self, event):
'''Explicitly set focus, so user can select and copy text'''
self.text.focus_set()
if __name__ == "__main__":
app = SampleApp()
app.mainloop()
#BryanOakley It took me a while to test your suggestion since I have no Mac.
Unfortunately Mac implementation of Python is buggy.
I've added focus, ie my disable function which I call after creating a window and inserting text, now calls first:
self.txt['state'] = 'disabled'
and then
self.txt.focus_set()
Which is what I think you've suggested.
It "kind of" worked. Ie: when selecting text (click and drag or double-click) highlighting works most of the time. Python must have some bad memory references or such bugs: Sometimes highlighting doesn't work at first, then it starts working (in the same window) after more clicking. Sometimes when program is invoked it works right of the bat. Sometimes selecting with Shift-rightArrow key will work but selecting with the mouse will not. Then starts working again. Or it will work fine in one window but not in another one (both of the same class), then starts working in all windows...etc...
The good thing is that adding focus did not affect badly Windows (ie all works fine as without focus.
I guess at this point I will just hope that future/next release of Python for Mac will fix those bugs..
BTW, it seems that Mac is a bit of an orphan for Python. Implementation is much uglier then for Windows. I mean the fonts look worse, the buttons, etc.. Or it could be due to different screen resolutions and Python ports that poorly account for those. Not sure
Anyway. Thank you for your help and suggestion to use focus for Mac.

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