My objective is to add a vertical scroll bar to a frame which has several labels in it. The scroll bar should automatically enabled as soon as the labels inside the frame exceed the height of the frame. After searching through, I found this useful post. Based on that post I understand that in order to achieve what i want, (correct me if I am wrong, I am a beginner) I have to create a Frame
first, then create a Canvas
inside that frame and stick the scroll bar to that frame as well. After that, create another frame and put it inside the canvas as a window object. So, I finally come up with this:
from Tkinter import *
def data():
for i in range(50):
Label(frame,text=i).grid(row=i,column=0)
Label(frame,text="my text"+str(i)).grid(row=i,column=1)
Label(frame,text="..........").grid(row=i,column=2)
def myfunction(event):
canvas.configure(scrollregion=canvas.bbox("all"),width=200,height=200)
root=Tk()
sizex = 800
sizey = 600
posx = 100
posy = 100
root.wm_geometry("%dx%d+%d+%d" % (sizex, sizey, posx, posy))
myframe=Frame(root,relief=GROOVE,width=50,height=100,bd=1)
myframe.place(x=10,y=10)
canvas=Canvas(myframe)
frame=Frame(canvas)
myscrollbar=Scrollbar(myframe,orient="vertical",command=canvas.yview)
canvas.configure(yscrollcommand=myscrollbar.set)
myscrollbar.pack(side="right",fill="y")
canvas.pack(side="left")
canvas.create_window((0,0),window=frame,anchor='nw')
frame.bind("<Configure>",myfunction)
data()
root.mainloop()
anchor='nw'
when creating window on canvas?Please keep your answer simple, as I am a beginner.
Please note that the proposed code is only valid with Python 2
Here is an example:
from Tkinter import * # from x import * is bad practice
from ttk import *
# http://tkinter.unpythonic.net/wiki/VerticalScrolledFrame
class VerticalScrolledFrame(Frame):
"""A pure Tkinter scrollable frame that actually works!
* Use the 'interior' attribute to place widgets inside the scrollable frame
* Construct and pack/place/grid normally
* This frame only allows vertical scrolling
"""
def __init__(self, parent, *args, **kw):
Frame.__init__(self, parent, *args, **kw)
# create a canvas object and a vertical scrollbar for scrolling it
vscrollbar = Scrollbar(self, orient=VERTICAL)
vscrollbar.pack(fill=Y, side=RIGHT, expand=FALSE)
canvas = Canvas(self, bd=0, highlightthickness=0,
yscrollcommand=vscrollbar.set)
canvas.pack(side=LEFT, fill=BOTH, expand=TRUE)
vscrollbar.config(command=canvas.yview)
# reset the view
canvas.xview_moveto(0)
canvas.yview_moveto(0)
# create a frame inside the canvas which will be scrolled with it
self.interior = interior = Frame(canvas)
interior_id = canvas.create_window(0, 0, window=interior,
anchor=NW)
# track changes to the canvas and frame width and sync them,
# also updating the scrollbar
def _configure_interior(event):
# update the scrollbars to match the size of the inner frame
size = (interior.winfo_reqwidth(), interior.winfo_reqheight())
canvas.config(scrollregion="0 0 %s %s" % size)
if interior.winfo_reqwidth() != canvas.winfo_width():
# update the canvas's width to fit the inner frame
canvas.config(width=interior.winfo_reqwidth())
interior.bind('<Configure>', _configure_interior)
def _configure_canvas(event):
if interior.winfo_reqwidth() != canvas.winfo_width():
# update the inner frame's width to fill the canvas
canvas.itemconfigure(interior_id, width=canvas.winfo_width())
canvas.bind('<Configure>', _configure_canvas)
if __name__ == "__main__":
class SampleApp(Tk):
def __init__(self, *args, **kwargs):
root = Tk.__init__(self, *args, **kwargs)
self.frame = VerticalScrolledFrame(root)
self.frame.pack()
self.label = Label(text="Shrink the window to activate the scrollbar.")
self.label.pack()
buttons = []
for i in range(10):
buttons.append(Button(self.frame.interior, text="Button " + str(i)))
buttons[-1].pack()
app = SampleApp()
app.mainloop()
It does not yet have the mouse wheel bound to the scrollbar but it is possible. Scrolling with the wheel can get a bit bumpy, though.
edit:
to 1)
IMHO scrolling frames is somewhat tricky in Tkinter and does not seem to be done a lot. It seems there is no elegant way to do it.
One problem with your code is that you have to set the canvas size manually - that's what the example code I posted solves.
to 2)
You are talking about the data function? Place works for me, too. (In general I prefer grid).
to 3)
Well, it positions the window on the canvas.
One thing I noticed is that your example handles mouse wheel scrolling by default while the one I posted does not. Will have to look at that some time.