使用PIL或枕头绘制图像并用TKinter显示

Question

I want to draw an image programmatically. Essentially I am talking about setting each single pixel as a map of the image, and I would like to do that using PIL/pillow. Then, I would like to display it on the screen. The GUI is based on TKinter.

root = Tk()
root.wm_title("Lands - A world generator")
root.resizable(0,0)

prepare_menu()

canvas = Canvas(root, width=canvas_width, height=canvas_height)
canvas.pack()

root.mainloop()

The prepare_menu sets the menu and associates one entry with an event handler, which calls the function show_elevation_map like this:

def show_elevation_map(p, width, height):    
    hm = platec.get_heightmap(p)
    img = PIL.Image.new('RGBA', (width, height))
    pixels = img.load()
    for y in range(0, height):
        for x in range(0, width):            
            pixels[x, y] = (255, 0, 0, 255)
    pi = ImageTk.PhotoImage(img)
    sprite = canvas.create_image(100, 100, image=pi)
    canvas.update()

I tried it like this, but I cannot see anything on the screen, while I would expect to see everything red. What am I doing wrong here?

Thanks.

Answer 1

Your image is likely getting garbage collected. You need to save a persistent reference to the image.