I am trying to use tkinter scale widget to increase or decrease a Label widget text size on the canvas. I am using the the scale widget variable value to do so. The text size changing when the button is clicked (my_btn) but I want it to change and I would like to increase or decrease the text size by dragging the scale widget left or right. When I am dragging the scale widget the program is prompting an error:
TypeError: <lambda>() takes 0 positional arguments but 1 was given.
The code is shown below. Please tell me how can I control the text size by dragging the scale widget directly.
##### Imports #####
from tkinter import *
from tkinter import ttk
###################################################################
# FUNCTIONS #
###################################################################
def slide(mainCanvas, textSlider):
slide.textLayer.place_forget()
slide.textLayer = Label(mainCanvas, text="TEST", font=('Arial', int(textSlider.get())), bg='white', fg='red')
slide.textLayer.place(relx=0.5, rely=0.5, anchor='center')
###################################################################
# MAIN #
###################################################################
def main():
root = Tk()
rootWidth = 500
rootHeight = 510
root.minsize(rootWidth, rootHeight)
mainFrameCanvas = Frame(root, bg='white', width=rootWidth, height=350)
mainFrameCanvas.pack(anchor='n')
mainCanvas = Canvas(mainFrameCanvas, width=rootWidth, height=350, bg='white', relief='solid', borderwidth=1)
mainCanvas.pack(fill='x', expand=1)
mainFrameSlider = Frame(root, bg='white', width=rootWidth, height=150, relief='solid', borderwidth=1)
mainFrameSlider.pack(anchor='s')
slide.textLayer = Label(mainCanvas, text="TEST", bg='white', fg='red')
slide.textLayer.place(relx=0.5, rely=0.5, anchor='center')
var = DoubleVar()
textSlider = Scale(mainFrameSlider, from_=10, to=30, variable=var, orient=HORIZONTAL, length=rootWidth*0.9, troughcolor='white', showvalue=1, bg='white', highlightbackground='white')
textSlider.bind("<Button-1>", lambda: slide(mainCanvas, textSlider))
textSlider.place(x=20, y=40)
my_btn = Button(root, text="Click Me!", command=lambda: slide(mainCanvas, textSlider)).pack()
root.mainloop()
###################################################################
# RUN #
###################################################################
def run():
print('\nStart script')
main()
print('Finished script')
run()
CodePudding user response:
Callback for an event binding expects an argument, the Event
object. So
textSlider.bind("<Button-1>", lambda: slide(mainCanvas, textSlider))
should be changed to:
textSlider.bind("<Button-1>", lambda e: slide(mainCanvas, textSlider))
Note that you don't need to remove and recreate the label inside slide()
, just update the font for the label:
def slide(mainCanvas, textSlider):
slide.textLayer.config(font=('Arial', int(textSlider.get())))