Tkinter Canvas without white background (make it transparent) - python

Hi I'm trying to make a canvas to create images onto it, but when I create the canvas, it has this ugly white background.
test_canvas = Canvas(main_window,100,100, bd=0, highlightthickness=0)
And after placing it, it has a white background.
Is there anyway to remove that background and make it blend in (be transparent)?
Here's an image to see the problem (I want that white background to disappear and blend in with the rest of the background)
https://imgur.com/a/FySWyyn

A windows only solution is to use the pywin32 modul and can be installed with:
pip install pywin32
With pywin32 you can alter the window exstyle and set the canvas to a layered window. A layered window can have a transparent colorkey and is done like in the exampel below:
import tkinter as tk
import win32gui
import win32con
import win32api
root = tk.Tk()
root.configure(bg='yellow')
canvas = tk.Canvas(root,bg='#000000')#full black
hwnd = canvas.winfo_id()
colorkey = win32api.RGB(0,0,0) #full black in COLORREF structure
wnd_exstyle = win32gui.GetWindowLong(hwnd, win32con.GWL_EXSTYLE)
new_exstyle = wnd_exstyle | win32con.WS_EX_LAYERED
win32gui.SetWindowLong(hwnd,win32con.GWL_EXSTYLE,new_exstyle)
win32gui.SetLayeredWindowAttributes(hwnd,colorkey,255,win32con.LWA_COLORKEY)
canvas.create_rectangle(50,50,100,100,fill='blue')
canvas.pack()
NOTE: AFTER DEFINING A TRANSPARENT COLORKEY EVERYTHING IN THAT CANVAS WITH THAT COLOR WILL BE TRANSPARENT!

Related

Tkinter Transparent Background macOS

I've been messing around with different code snippets and combinations for a while now, trying to make it so my .gif file would have a transparent background. I've been successful in making the actual background transparent, but I find that my .gif goes transparent with it:
import tkinter as tk
root = tk.Tk()
root.overrideredirect(1)
root.wm_attributes("-topmost", True)
root.wm_attributes("-transparent", True)
root.config(bg='systemTransparent')
root.geometry("+300+300")
root.image = tk.PhotoImage(file="sample.gif")
label = tk.Label(root, image=root.image)
label.config(bg='systemTransparent')
label.pack()
root.mainloop()
I have found that whenever I use both root.config(bg='systemTransparent') and label.config(bg='systemTransparent'), the entire window and gif go transparent, but when I use just one or neither, I am left with a light-gray background.

Desktop Goose like program

i have been trying to create a python program similar to desktop goose in the aspect of a widget moving freely around the screen.
First i tried to create a window with tkinter and make a transparent window
with a PNG picture of a character and then moving the window with win32gui or any other library that would allow me to do this.
But first, the tkinter transparent window thing doesn't work because the widgets inherit the transparency, so there is no way i can display the PNG.
Then i had trouble finding any win32gui function that would allow me to move the windows, i just found stuff that would let me resize them.
Is there any way i can do any of these two tasks?
You can create a transparent window using a transparent PNG image as below:
import tkinter as tk
# select a color as the transparent color
TRNAS_COLOR = '#abcdef'
root = tk.Tk()
root.overrideredirect(1)
root.attributes('-transparentcolor', TRNAS_COLOR)
image = tk.PhotoImage(file='/path/to/image.png')
tk.Label(root, image=image, bg=TRNAS_COLOR).pack()
# support dragging window
def start_drag(event):
global dx, dy
dx, dy = event.x, event.y
def drag_window(event):
root.geometry(f'+{event.x_root-dx}+{event.y_root-dy}')
root.bind('<Button-1>', start_drag)
root.bind('<B1-Motion>', drag_window)
root.mainloop()
Then you can use root.geometry(...) to move the root window.

Unable to put transparent PNG over a normal image Python Tkinter

So I have 2 images, 1 image is supposed to be the background and the other 1 is just an image of a character.
I am able to put one image over the other but the image has white borders even though it's a PNG file.
This is how it looks like:
This is how I want it to look like:
Here are the two separte images:
https://imgur.com/a/SmE5lgC
Sorry that I didnt post the images directly but I can not since I do no have 10 reputation points.
I've tried converting it to RGBA but same thing happened.
from tkinter import *
from PIL import Image
root = Tk()
root.title("Game")
background = PhotoImage(file="back.png")
backgroundlabel = Label(root, image=background)
backgroundlabel.pack()
character = PhotoImage(file="hero.png")
characterlabel = Label(root, image=character)
characterlabel.place(x=0,y=0)
root.mainloop()
You just need to use the canvas widget in Tkinter. Only the canvas widget supports transparency. This has to do with how Tkinter draws the display. As of right now, your code is just overlaying two images. Tkinter does not know how to compose them with transparency unless you use the canvas widget.
See the following code:
from tkinter import *
from PIL import Image
root = Tk()
root.title("Game")
frame = Frame(root)
frame.pack()
canvas = Canvas(frame, bg="black", width=700, height=400)
canvas.pack()
background = PhotoImage(file="background.png")
canvas.create_image(350,200,image=background)
character = PhotoImage(file="hero.png")
canvas.create_image(30,30,image=character)
root.mainloop()
All I did was download the images you provided. I did not modify the images. So, the bottom line is that you just need to use the canvas widget.
VoilĂ !
Note: The question asked is a duplicate of How do I make Tkinter support PNG transparency?

Tkinter: Display an image on top of other [duplicate]

I am making a chess program and I want to be able to drag the pieces. In order to do this, I put the image of the piece on a Canvas so it can be dragged (I can also use a Label if I want). However, when I drag the piece there is a white square that surrounds the image of the piece.
When I researched the problem, many people gave this solution:
drag_canvas = Canvas(self, height=80, width=80, bg="yellow")
root.wm_attributes("-transparentcolor", "yellow")
This caused the background to be transparent but it was not the chessboard that was visible, it was the program behind the GUI
.
Is there any way I can have the background be transparent and show the chessboard behind rather than the program behind the tkinter window?
Note: I do not mind using any other widget (e.g. a Label) but they must use modules that come default with Python (so no PIL) as this program needs to be used in an environment where I cannot download other modules.
Question: How to make a tkinter canvas background transparent?
The only possible config(... option, to set the background to nothing
c.config(bg='')
results with: _tkinter.TclError: unknown color name ""
To get this result:
you have to hold the chess board and figures within the same .Canvas(....
self.canvas = Canvas(self, width=500, height=200, bd=0, highlightthickness=0)
self.canvas.create_rectangle(245,50,345,150, fill='white')
self.image = tk.PhotoImage(file='chess.png')
self.image_id = self.canvas.create_image(50,50, image=self.image)
self.canvas.move(self.image_id, 245, 100)
Tested with Python: 3.5 - TkVersion: 8.6
A windows only solution is to use the pywin32 module that can be installed with:
pip install pywin32
With pywin32 you can alter the window exstyle and set the canvas to a layered window. A layered window can have a transparent colorkey and is done in the example below:
import tkinter as tk
import win32gui
import win32con
import win32api
root = tk.Tk()
root.configure(bg='yellow')
canvas = tk.Canvas(root,bg='#000000')#full black
hwnd = canvas.winfo_id()
colorkey = win32api.RGB(0,0,0) #full black in COLORREF structure
wnd_exstyle = win32gui.GetWindowLong(hwnd, win32con.GWL_EXSTYLE)
new_exstyle = wnd_exstyle | win32con.WS_EX_LAYERED
win32gui.SetWindowLong(hwnd,win32con.GWL_EXSTYLE,new_exstyle)
win32gui.SetLayeredWindowAttributes(hwnd,colorkey,255,win32con.LWA_COLORKEY)
canvas.create_rectangle(50,50,100,100,fill='blue')
canvas.pack()
Explaination:
First we need the handle of the window which is called hwnd and we can get it in tkinter by .winfo_id().
Next we get the actual extended window style by GetWindowLong and ask specific for extended style information with win32con.GWL_EXSTYLE.
After that we do a bitwise operation in hexadezimal to alter the style with wnd_exstyle | win32con.WS_EX_LAYERED the result is our new_style.
Now we can set the extended style to the window with SetWindowLong. Finally we have our LayeredWindow which has additional Attributes we can work with. A transparent ColorKey can be set with SetLayeredWindowAttributes while we just use LWA_COLORKEY the alpha parameter has no use to us.
Important note: After defining a transparent colorkey, everything in that canvas with that color will be transparent.

How do I make Tkinter support PNG transparency?

I put in a partially transparent PNG image in Tkinter and all I get is this
How do I make the dark triangle on the right clear? (like it's supposed to be)
This is python 2.6 on Windows 7, btw.
Here's an example (the PNG file example.png has lots of transparency in different places):
from Tkinter import Tk, Frame, Canvas
import ImageTk
t = Tk()
t.title("Transparency")
frame = Frame(t)
frame.pack()
canvas = Canvas(frame, bg="black", width=500, height=500)
canvas.pack()
photoimage = ImageTk.PhotoImage(file="example.png")
canvas.create_image(150, 150, image=photoimage)
t.mainloop()
You need to make sure the image has been stored as "RGBA" which is RGB with an alpha channel. You can check for that using a graphics program of your choice, or using PIL (Python Imaging Library):
import Image
im = Image.open("button.png")
print im.mode
This should print "RGBA". If not, you'll have to make sure the alpha channel is saved with the image. You'll have to consult your graphics program manual for how to do that.

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