Python Tkinter Scrollbar

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This widget provides a slide controller that is used to implement vertical scrolled widgets, such as Listbox, Text and Canvas. Note that you can also create horizontal scrollbars on Entry widgets.

Syntax:

Here is the simple syntax to create this widget:

 w = Scrollbar ( master, option, ... )

Parameters:

  • master: This represents the parent window.

  • options: Here is the list of most commonly used options for this widget. These options can be used as key-value pairs separated by commas.

OptionDescription
activebackground The color of the slider and arrowheads when the mouse is over them.
bg The color of the slider and arrowheads when the mouse is not over them.
bd The width of the 3-d borders around the entire perimeter of the trough, and also the width of the 3-d effects on the arrowheads and slider. Default is no border around the trough, and a 2-pixel border around the arrowheads and slider.
command A procedure to be called whenever the scrollbar is moved.
cursor The cursor that appears when the mouse is over the scrollbar.
elementborderwidth The width of the borders around the arrowheads and slider. The default is elementborderwidth=-1, which means to use the value of the borderwidth option.
highlightbackground The color of the focus highlight when the scrollbar does not have focus.
highlightcolor The color of the focus highlight when the scrollbar has the focus.
highlightthickness The thickness of the focus highlight. Default is 1. Set to 0 to suppress display of the focus highlight.
jump This option controls what happens when a user drags the slider. Normally (jump=0), every small drag of the slider causes the command callback to be called. If you set this option to 1, the callback isn't called until the user releases the mouse button.
orient Set orient=HORIZONTAL for a horizontal scrollbar, orient=VERTICAL for a vertical one.
repeatdelay This option controls how long button 1 has to be held down in the trough before the slider starts moving in that direction repeatedly. Default is repeatdelay=300, and the units are milliseconds.
repeatinterval repeatinterval
takefocus Normally, you can tab the focus through a scrollbar widget. Set takefocus=0 if you don't want this behavior.
troughcolor The color of the trough.
width Width of the scrollbar (its y dimension if horizontal, and its x dimension if vertical). Default is 16.

Methods:

Scrollbar objects have these methods:

MethodsDescription
get()Returns two numbers (a, b) describing the current position of the slider. The a value gives the position of the left or top edge of the slider, for horizontal and vertical scrollbars respectively; the b value gives the position of the right or bottom edge.
set ( first, last )To connect a scrollbar to another widget w, set w's xscrollcommand or yscrollcommand to the scrollbar's set() method. The arguments have the same meaning as the values returned by the get() method.

Example:

Try the following example yourself:

from Tkinter import *

root = Tk()
scrollbar = Scrollbar(root)
scrollbar.pack( side = RIGHT, fill=Y )

mylist = Listbox(root, yscrollcommand = scrollbar.set )
for line in range(100):
   mylist.insert(END, "This is line number " + str(line))

mylist.pack( side = LEFT, fill = BOTH )
scrollbar.config( command = mylist.yview )

mainloop()

When the above code is executed, it produces the following result:

TK Scrollbar

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