tkinter image appearing partially white instead of correct colour - python-3.x

Recently i have been trying to get gifs to work with tkinter and after some research i figured out how i was going to do it and wrote a class to make playing them easier
class GifWrapper():
def __init__(self, parent, file=None):
self.file=file
self.parent=parent
if file:
self.info=parse(file=file)
else:
raise GifError("expected file to be passed")
print(str(self.info.frames)+" "+str(len(self.info.delays)))
self.frames=[]
for i in range(0, self.info.frames):
self.frames.append(PhotoImage(file=self.file, format="gif -index {}".format(i)))
print("added frame {}".format(i))
async def play(self):
curFrame=0
for i in self.info.delays:
await asyncio.sleep(i/100)
self.parent["image"]=self.frames[curFrame]
curFrame+=1
However when i tested this out i noticed that my gif was pretty strange as seen here, the first frame seems to be only slightly affected, the second frame seems perfectly ok and the rest are pretty badly affected by the issue, i remember reading somewhere that pixels with an alpha of 0 were treated as transparent in PhotoImage files so i assume that this might be the problem however i think it's weird that the first and second images are affected differently, is there a way to change this?

Related

Tkinter and some kind of issue when trying to display images

First off, I'm very new to Python and coding in general. I'm using Python, Tkinter, and Idle version 3.7.3. I'm using an HP Chromebook, with Chrome OS Version 81.0.4044.141.
from tkinter import *
window = Tk()
window.title('Image Example')
img = PhotoImage(file = 'python.gif')
label = Label(window, image = img)
label.pack()
window.mainloop()
As you can see above, this is the small snippet of code that I'm having issues with. As far as I understand, everything is written correctly and the file "python.gif" is in the correct directory. For reference this is what the image should look like:
python.gif (normal)
But when I run the program, this is what I get:
python.gif (screenshot of running program)
That's the result 99% of the time, but I should mention that there have been a RARE number of occasions where the image displayed correctly upon program execution. However, I do not know how to replicate that. Also for more context, I've tried other images to see what happened. I found a free .pgm image to try as an example, and upon execution either I got the same result, or half of the image would appear correctly while the bottom half (also sometimes this would be reversed and the top half would be affected) would be "blacked out".
In conclusion, I wanted to ask if anybody has an idea of what's going on. I'm not sure if this is a hardware issue (because I can view all mentioned images in a normal image viewing app with no problems), or if this has something to do with Python/Tkinter.
Any assistance is very appreciated! Please and Thank You!

Maximize figures before saving

The question about how to do maximize a window before saving has been asked several times and has several questions (still no one is portable, though), How to maximize a plt.show() window using Python
and How do you change the size of figures drawn with matplotlib?
I created a small function to maximize a figure window before saving the plots. It works with QT5Agg backend.
import matplotlib.pyplot as plt
def maximize_figure_window(figures=None, tight=True):
"""
Maximize all the open figure windows or the ones indicated in figures
Parameters
----------
figures: (list) figure numbers
tight : (bool) if True, applies the tight_layout option
:return:
"""
if figures is None:
figures = plt.get_fignums()
for fig in figures:
plt.figure(fig)
manager = plt.get_current_fig_manager()
manager.window.showMaximized()
if tight is True:
plt.tight_layout()
Problems:
I have to wait for the windows to be actually maximized before using the plt.savefig() command, otherwise it is saved with as not maximized. This is a problem if I simply want to use the above function in a script
(minor problems:)
2. I have to use the above function twice in order to get the tight_layout option working, i.e. the first time tight=True has no effect.
The solution is not portable. Of course I can add all the possible backend I might use, but that's kind of ugly.
Questions:
how to make the script wait for the windows to be maximized? I don't want to use time.sleep(tot_seconds) because tot_seconds would be kind of arbitrary and makes the function even less portable
how to solve problem 2 ? I guess it is related to problem 1.
is there a portable solution to "maximize all the open windows" problem?
-- Edit --
For problem 3. #DavidG suggestion sounds good. I use tkinter to automatically get width and height, convert them to inches, and use them in fig.set_size_inches or directly during the figure creation via fig = plt.figure(figsize=(width, height)).
So a more portable solution is, for example.
import tkinter as tk
import matplotlib.pyplot as plt
def maximize_figure(figure=None):
root = tk.Tk()
width = root.winfo_screenmmwidth() / 25.4
height = root.winfo_screenmmheight() / 25.4
if figure is not None:
plt.figure(figure).set_size_inches(width, height)
return width, height
where I allow the figure to be None so that I can use the function to just retrieve width and height and use them later.
Problem 1 is still there, though.
I use maximize_figure() in a plot function that I created (let's say my_plot_func()) but still the saved figure doesn't have the right dimensions when saved on file.
I also tried with time.sleep(5) in my_plot_func() right after the figure creation. Not working.
It works only if a manually run in the console maximize_figure() and then run my_plot_func(figure=maximized_figure) with the figure already maximized. Which means that dimension calculation and saving parameters are correct.
It does not work if I run in the console maximize_figure() and my_plot_func(figure=maximized_figure) altogether, i.e. with one call the the console! I really don't get why.
I also tried with a non-interactive backend like 'Agg', so that the figure doesn't get actually created on screen. Not working (wrong dimensions) no matter if I call the functions altogether or one after the other.
To summarize and clarify (problem 1):
by running these two pieces of code in console, figure gets saved correctly.
plt.close('all')
plt.switch_backend('Qt5Agg')
fig = plt.figure()
w, h = maximize_figure(fig.number)
followed by:
my_plot_func(out_file='filename.eps', figure=fig.number)
by running them together (like it would be in a script) figure is not saved correctly.
plt.close('all')
plt.switch_backend('Qt5Agg')
fig = plt.figure()
w, h = maximize_figure(fig.number)
my_plot_func(out_file='filename.eps', figure=fig.number)
Using
plt.switch_backend('Agg')
instead of
plt.switch_backend('Qt5Agg')
it does not work in both cases.

Pyglet hello world example doesn't show label until a key is pressed

import pyglet
window = pyglet.window.Window()
label = pyglet.text.Label("Hello World!",
font_name="Times New Roman",
color=(255,255,255,255),
font_size=36,
x=window.width//2, y=window.height//2,
anchor_x="center", anchor_y="center")
#window.event
def on_draw():
window.clear()
label.draw()
pyglet.app.run()
This code is taken from the pyglet tutorial at https://pyglet.readthedocs.io/en/pyglet-1.2-maintenance/programming_guide/quickstart.html but when run it doesn't draw the label until any key is pressed. I added the color as I thought the text may have defaulted to black.
Am I missing something really obvious as to why this behaviour is happening?
OK, having had my memory jogged by the comments, I installed the MS Fonts and it now works in python 2.x but I still need to press a key to see the text in python 3. Maybe the font thing is a red-herring and there is some incompatibility with python 3.
As mentioned in the comments.
Most examples found on the internet (even most guides) assume a Windows platform.
If there's a font= declaration with a Windows font but you're running Linux, make sure you got the proper fonts installed or revert to a font you've got installed.
$ fc-list
Also not declaring a font will work too:
label = pyglet.text.Label("Hello World!",
color=(255,255,255,255),
font_size=36,
x=window.width//2, y=window.height//2,
anchor_x="center", anchor_y="center")
Because Pyglet will default to sans-serif:
If you do not particularly care which font is used, and just need to display some readable text, you can specify None as the family name, which will load a default sans-serif font (Helvetica on Mac OS X, Arial on Windows XP)
Your issue is probably that you don't manually update the screen after you drew something. Normally when you press a key, it forces a window.flip(), which basically means update the screen content.
window.clear() also triggers this behavior, but x.draw() does not. Why? Well the thing that takes time in computer graphics is not really the calculations, it's the updating them to the screen that takes time.. There for .draw() doesn't update the screen, it just puts the stuff in the graphical buffer ("page"), you decide when to flip the page and show the new buffer on the screen.
Try this out:
#window.event
def on_draw():
window.clear()
label.draw()
window.flip()
This might be a overkill solution, but it will probably solve the problem.
This overrides the default loop of pyglet and the default draw behavior, it's also one of the classes i use the most in my pyglet projects since it gives me the option to create my own framework.
import pyglet
class Window(pyglet.window.Window):
def __init__(self):
super(Window, self).__init__(vsync = False)
self.sprites = {}
self.sprites['testlabel'] = label = pyglet.text.Label("Hello World!",
color=(255,255,255,255),
font_size=36,
x=self.width//2, y=self.height//2, #self here, being pyglet.window.Window that we've inherited and instanciated with super().
anchor_x="center", anchor_y="center")
self.alive = 1
def on_draw(self):
self.render()
def render(self):
self.clear()
for sprite_name, sprite_obj in self.sprites.items():
sprite_obj.draw()
self.flip()
def on_close(self):
self.alive = 0
def run(self):
while self.alive:
self.render()
# This is very important, this queries (and empties)
# the pyglet event queue, if this queue isn't cleared
# pyglet will hang because it can't input more events,
# and a full buffer is a bad buffer, so we **NEED** this!
event = self.dispatch_events()
win = Window()
win.run()
It's extremely basic, but you can add more sprites, objects and render them in def render(self):.

wxPython from Linux to Windows

I have a wxPython application developed on Linux that I wish to deploy on Windows machines. While most of the things work well on porting there are small (but catastrophic) problems, none of which seem related. Rather than list them all, I'll start with one.
I have an array of images that I read in and place in a GridBagSizer in a Class. Unfortunately, the 'Bind' statement doesn't seem to take effect, and when I double-click on an image 'onSuitDClick' is not called.
suitSizer=SuitDisplay(self, suit
def onSuitDClick(self, event):
print 'sc'
class SuitDisplay(wx.Panel):
def __init__(self, frame, suit):
wx.Panel.__init__(self, frame, id=wx.ID_ANY)
suitSizer=wx.GridBagSizer(1, 13)
suitList=[]
for ii in range(0, len(g.CARDS)):
if g.CARDS[ii]+g.SUITS[suit] in frame.availableCards:
card=g.CARDS[ii]+g.SUITS[suit]
suitList.append(card)
for ii in range(0, len(suitList)):
card= suitList[ii]
image = wx.Bitmap(frame.imageFolder+card+'.png',wx.BITMAP_TYPE_PNG).ConvertToImage()
img = wx.StaticBitmap(self, -1, image.ConvertToBitmap(), name=card)
img.Bind(wx.EVT_LEFT_DCLICK, frame.onSuitDClick)
suitSizer.Add(img, pos=(0,cardPos), flag=wx.LEFT, border=border)
self.SetSizer(suitSizer)
Needless to say, this works perfectly in Linux.
Can anyone suggest where I might look for a solution?

Can a tkinter button return a value from an entry on-click?

I'm doing an extended project as one of my qualifications in my current College and I chose to write a python Strategy/RPG game. As a result, I ended up with the highest level of Python knowledge (Surpassing my Computing Teacher who only ever uses the basics... and used Tkinter only once a few years ago. Every one else who has decided to make a program, are either coding in Lua, Java, C++, HTML/CSS/Java-Script or, those who are coding in python, they are only using the basics learned from our teacher.)
I say "Highest level of Python knowledge" but really it isn't that high... I only know a little beyond the basics.
As a result, a forum post is the best place I can turn to for help.
So in my game I defined this function:
#"Given_String" is the question that one would want to ask. (With the answer being an integer between 1 and "Choice_Range" (inclusive)
def Value_Error(Given_String,Error_Message,Choice_Range):
while True:
try:
Temp=int(input(Given_String))
if Temp<1 or Temp>Choice_Range:
print(Error_Message)
else:
break
except ValueError:
print(Error_Message)
return Temp
I then wanted to add tkinter to my code, because the game would have to be in a separate window, and not in the console. As a result, I had to change this code so that it displays the "Given_Message" and the "Error_Message" in a tkinter window, and uses the value that has been typed into an entry box when defining "Temp".
I wrote this code to make this work: (Or at least most of it)
#This code is stored in a different file for neatness and hence I had to import "sys" to avoid circular imports.
#This code is made to be flexible so that I can later re-use it when necessary.
#This code starts with the function all the way at the bottom. The rest are made to add flexibility and to structure the algorithm.
#This code hasn't been fully run (Because of the Error crashing the Python Shell) so it can contain other Run-time Errors that I'm not aware of yet.
import sys
def Generate_Window(Window_Name,X_Parameter=5,Y_Parameter=50):
Temp=sys.modules['tkinter'].Tk()
Temp.title(Window_Name)
Temp.geometry(str(X_Parameter)+"x"+str(Y_Parameter))
return Temp
def Generate_Button(Master,Text="Submit"):
Temp=sys.modules["tkinter"].Button(Master,text=Text)
return Temp
def Generate_Entry(Master):
Temp=sys.modules["tkinter"].Entry(Master)
return Temp
def Generate_Label(Master,Given_String):
Temp=sys.modules["tkinter"].Label(Master,text=Given_String)
return Temp
def Com_Get_Entry(Given_Window,Given_Entry):
Temp=Given_Entry.get()
Given_Window.destroy()
return Temp
def Com_Confirm(Given_Window):
Given_Window.destroy()
def Generate_Entry_Box(Given_String):
Entry_Window=Generate_Window("Entry",X_Parameter=300)
Entry_Label=Generate_Label(Entry_Window,Given_String)
Entry_Entry=Generate_Entry(Entry_Window)
Entry_Button=Generate_Button(Entry_Window)
Entry_Button.configure(command=lambda:Com_Get_Entry(Entry_Window,Entry_Entry))
Entry_Label.grid(row=0,columnspan=2)
Entry_Entry.grid(row=1,column=0)
Entry_Button.grid(row=1,column=1)
def Generate_Alert_Message(Given_String):
Alert_Window=Generate_Window("Alert",X_Parameter=300)
Alert_Label=Generate_Label(Alert_Window,Given_String)
Alert_Button=Generate_Button(Alert_Window,Text="OK")
Alert_Button.configure(command=lambda:Com_Confirm(Alert_Window))
Alert_Label.grid(row=0,columnspan=2)
Alert_Button.grid(row=1,column=1)
def Get_Interger_Input_In_Range(Given_String,Error_Message,Choice_Range):
while True:
try:
Returned_Value=int(Generate_Entry_Box(Given_String))
if Returned_Value<1 or Returned_Value>Choice_Range:
Generate_Alert_Message(Error_Message)
else:
break
except ValueError:
Generate_Alert_Message(Error_Message)
return Temp
I already included in my code all that I was struggling with and that I could find an answer to.
I.E: On-click, do a certain action with given parameters.
One thing I could not find, is how to return the entered value to the original (Get_Interger_Input_In_Range()) function after the button has been clicked.
What I mean is something like this:
def Function1(GivenParameter1,GivenParameter2):
Temp=Function2(GivenParameter1)
Temp+=GiverParameter2 #random action
return Temp
def Function2(GivenParameter):
Button=Button(Master,command=Function3).grid()
Entry=Entry(Master).grid()
def Function3():
Temp=Entry.get()
return Temp
In Function1 I want Temp to equal the entered value from Function2.
Is there any way to do this without using classes? (I'm not too familiar with classes yet)
Is there any way to do this at all?
I haven't seen anyone give the answer I was looking for...
Because even if they said to use classes... I still didn't know how to return it (Explanation just below)
#The following code was written quickly for purposes of explaining what I mean. It doesn't actually work... (It seems that the button command is being called automatically...)
from tkinter import *
class Return_Value_In_Entry():
def __init__(self):
self.Master=Tk()
self.Entry=Entry(self.Master)
self.Button=Button(self.Master,text="Submit",command=self.Return())
def Return(self):
self.TempVar=self.Entry.get()
return self.TempVar
The way I see it, the Return() function would return the value to the button and not the function/assignment that called the class ... Which is the same problem I'm having with my code.
If you read this all then I really appreciate it. I hope someone can answer my question and tell me (if it's impossible otherwise) how to use classes to solve my "Little" yet large problem.
I fixed your example code (I think). The main problem is that this:
command=self.Return()
does not do what you think it does. It just assigns return value from Return() to command. This is incorrect. It should be
command=self.Return
This assigns function Return to command. Subsequently, when ever button is pressed, self.Return() is executed.
The full example is here:
from tkinter import *
class Return_Value_In_Entry():
def __init__(self):
self.Master=Tk()
self.Entry=Entry(self.Master)
self.Entry.pack()
self.Button=Button(self.Master,text="Submit",command=self.Return)
self.Button.pack()
self.Master.mainloop()
def Return(self):
self.TempVar=self.Entry.get()
print(self.TempVar)
Return_Value_In_Entry()
Now, whenever you press the Button, the value from the Entry widget is saved into self.TempVar and printed out, just to check if its working. Hope this helps.
Gif showing how the example program works:

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