Tkinter List of Canvases

[ChalaoAdda]

On Tue, 10 Nov 2020 17:21:04 +0000, MRAB wrote:

> On 2020-11-10 10:01, ChalaoAdda wrote:
>> Hello,
>> 
>> I have a list of canvas of images. I would like to display all the
>> images. But it displays the last image. Here is my code.
>> 
>> from tkinter import *
>> from PIL import Image, ImageTk
>> 
>> root = Tk()
>> 
>> canvas_width = 265 canvas_height = 130 canvases = []
>> 
>> r, c = 0, 0
>> 
>> for tile in tiles:
>>      img = tile.image photo = ImageTk.PhotoImage(image=img)
>>      can = Canvas(root, width=canvas_width, height=canvas_height)
>>      can.create_image(0, 0, image=photo, anchor=NW)
>>      canvases.append(can)
>>      can.grid(row=r, column=c)
>> 
>>     c += 1
>>      if c % 5 == 0:
>>          r += 1 c = 0
>> 
>> 
>> root.mainloop()
>> 
> You need to keep a reference to the images. In your code, 'photo' still
> refers to the last photoimage, so that's why it's displayed; there are
> no references to the others, so they're garbage-collected. (You probably
> expected that 'create_image' would keep a reference to the image, but it
> doesn't. tkinter has its idiosyncrasies!)
> 
> Try adding a list for the photoimages:
> 
> ...
> photos = []
> 
> for tile in tiles:
>      img = tile.image photo = ImageTk.PhotoImage(image=img)
>      photos.append(photo)
>      can = Canvas(root, width=canvas_width, height=canvas_height)
> ...

Thanks a lot.