not a complete answer, but have you considered creating your own scrollbar lookalike:
import tkinter as tk
class MyScrollbar(tk.Canvas):
def __init__(self, master, *args, **kwargs):
if 'width' not in kwargs:
kwargs['width'] = 10
if 'bd' not in kwargs:
kwargs['bd'] = 0
if 'highlightthickness' not in kwargs:
kwargs['highlightthickness'] = 0
self.command = kwargs.pop('command')
tk.Canvas.__init__(self, master, *args, **kwargs)
self.elements = { 'button-1':None,
'button-2':None,
'trough':None,
'thumb':None}
self._oldwidth = 0
self._oldheight = 0
self._sb_start = 0
self._sb_end = 1
self.bind('<Configure>', self._resize)
self.tag_bind('button-1', '<Button-1>', self._button_1)
self.tag_bind('button-2', '<Button-1>', self._button_2)
self.tag_bind('trough', '<Button-1>', self._trough)
self._track = False
self.tag_bind('thumb', '<ButtonPress-1>', self._thumb_press)
self.tag_bind('thumb', '<ButtonRelease-1>', self._thumb_release)
self.tag_bind('thumb', '<Leave>', self._thumb_release)
self.tag_bind('thumb', '<Motion>', self._thumb_track)
def _sort_kwargs(self, kwargs):
for key in kwargs:
if key in ['buttontype', 'buttoncolor', 'troughcolor', 'thumbcolor', 'thumbtype']:
self._scroll_kwargs[key] = kwargs.pop(key) # add to custom dict and remove from canvas dict
return kwargs
def _resize(self, event):
width = self.winfo_width()
height = self.winfo_height()
# print("canvas: (%s, %s)" % (width, height))
if self.elements['button-1']: # exists
if self._oldwidth != width:
self.delete(self.elements['button-1'])
self.elements['button-1'] = None
else:
pass
if not self.elements['button-1']: # create
self.elements['button-1'] = self.create_oval((0,0,width, width), fill='#006cd9', outline='#006cd9', tag='button-1')
if self.elements['button-2']: # exists
coords = self.coords(self.elements['button-2'])
if self._oldwidth != width:
self.delete(self.elements['button-2'])
self.elements['button-2'] = None
elif self._oldheight != height:
self.move(self.elements['button-2'], 0, height-coords[3])
else:
pass
if not self.elements['button-2']: # create
self.elements['button-2'] = self.create_oval((0,height-width,width, height), fill='#006cd9', outline='#006cd9', tag='button-2')
if self.elements['trough']: # exists
coords = self.coords(self.elements['trough'])
if (self._oldwidth != width) or (self._oldheight != height):
self.delete(self.elements['trough'])
self.elements['trough'] = None
else:
pass
if not self.elements['trough']: # create
self.elements['trough'] = self.create_rectangle((0,int(width/2),width, height-int(width/2)), fill='#00468c', outline='#00468c', tag='trough')
self.set(self._sb_start, self._sb_end) # hacky way to redraw thumb
self.tag_raise('thumb') # ensure thumb always on top of trough
self._oldwidth = width
self._oldheight = height
def _button_1(self, event):
self.command('scroll', -1, 'pages')
return 'break'
def _button_2(self, event):
self.command('scroll', 1, 'pages')
return 'break'
def _trough(self, event):
width = self.winfo_width()
height = self.winfo_height()
size = (self._sb_end - self._sb_start) / 1
thumbrange = height - width
thumbsize = int(thumbrange * size)
thumboffset = int(thumbrange * self._sb_start) + int(width/2)
thumbpos = int(thumbrange * size / 2) + thumboffset
if event.y < thumbpos:
self.command('scroll', -1, 'pages')
elif event.y > thumbpos:
self.command('scroll', 1, 'pages')
return 'break'
def _thumb_press(self, event):
print("thumb press: (%s, %s)" % (event.x, event.y))
self._track = True
def _thumb_release(self, event):
print("thumb release: (%s, %s)" % (event.x, event.y))
self._track = False
def _thumb_track(self, event):
if self._track:
# print("*"*30)
print("thumb: (%s, %s)" % (event.x, event.y))
width = self.winfo_width()
height = self.winfo_height()
# print("window size: (%s, %s)" % (width, height))
size = (self._sb_end - self._sb_start) / 1
# print('size: %s' % size)
thumbrange = height - width
# print('thumbrange: %s' % thumbrange)
thumbsize = int(thumbrange * size)
# print('thumbsize: %s' % thumbsize)
clickrange = thumbrange - thumbsize
# print('clickrange: %s' % clickrange)
thumboffset = int(thumbrange * self._sb_start) + int(width/2)
# print('thumboffset: %s' % thumboffset)
thumbpos = int(thumbrange * size / 2) + thumboffset
# print("mouse point: %s" % event.y)
# print("thumbpos: %s" % thumbpos)
point = (event.y - (width/2) - (thumbsize/2)) / clickrange
# point = (event.y - (width / 2)) / (thumbrange - thumbsize)
# print(event.y - (width/2))
# print(point)
if point < 0:
point = 0
elif point > 1:
point = 1
# print(point)
self.command('moveto', point)
return 'break'
def set(self, *args):
oldsize = (self._sb_end - self._sb_start) / 1
self._sb_start = float(args[0])
self._sb_end = float(args[1])
size = (self._sb_end - self._sb_start) / 1
width = self.winfo_width()
height = self.winfo_height()
if oldsize != size:
self.delete(self.elements['thumb'])
self.elements['thumb'] = None
thumbrange = height - width
thumbsize = int(thumbrange * size)
thumboffset = int(thumbrange * self._sb_start) + int(width/2)
if not self.elements['thumb']: # create
self.elements['thumb'] = self.create_rectangle((0, thumboffset,width, thumbsize+thumboffset), fill='#4ca6ff', outline='#4ca6ff', tag='thumb')
else: # move
coords = self.coords(self.elements['thumb'])
if (thumboffset != coords[1]):
self.move(self.elements['thumb'], 0, thumboffset-coords[1])
return 'break'
if __name__ == '__main__':
root = tk.Tk()
lb = tk.Listbox(root)
lb.pack(side='left', fill='both', expand=True)
for num in range(0,100):
lb.insert('end', str(num))
sb = MyScrollbar(root, width=50, command=lb.yview)
sb.pack(side='right', fill='both', expand=True)
lb.configure(yscrollcommand=sb.set)
root.mainloop()
I've left my comments in, and for the life of me i can't seem to get click and dragging the thumb to work correctly, but its a simple scrollbar with the following features:
- up and down buttons that can be coloured
- thumb and trough that can be individually coloured
- tracks movement in scrollable widget
- thumb resizes with size of scroll area
Edit
I've revised the thumb code to fix the click and drag scrolling:
import tkinter as tk
class MyScrollbar(tk.Canvas):
def __init__(self, master, *args, **kwargs):
self._scroll_kwargs = { 'command':None,
'orient':'vertical',
'buttontype':'round',
'buttoncolor':'#006cd9',
'troughcolor':'#00468c',
'thumbtype':'rectangle',
'thumbcolor':'#4ca6ff',
}
kwargs = self._sort_kwargs(kwargs)
if self._scroll_kwargs['orient'] == 'vertical':
if 'width' not in kwargs:
kwargs['width'] = 10
elif self._scroll_kwargs['orient'] == 'horizontal':
if 'height' not in kwargs:
kwargs['height'] = 10
else:
raise ValueError
if 'bd' not in kwargs:
kwargs['bd'] = 0
if 'highlightthickness' not in kwargs:
kwargs['highlightthickness'] = 0
tk.Canvas.__init__(self, master, *args, **kwargs)
self.elements = { 'button-1':None,
'button-2':None,
'trough':None,
'thumb':None}
self._oldwidth = 0
self._oldheight = 0
self._sb_start = 0
self._sb_end = 1
self.bind('<Configure>', self._resize)
self.tag_bind('button-1', '<Button-1>', self._button_1)
self.tag_bind('button-2', '<Button-1>', self._button_2)
self.tag_bind('trough', '<Button-1>', self._trough)
self._track = False
self.tag_bind('thumb', '<ButtonPress-1>', self._thumb_press)
self.bind('<ButtonRelease-1>', self._thumb_release)
# self.bind('<Leave>', self._thumb_release)
self.bind('<Motion>', self._thumb_track)
def _sort_kwargs(self, kwargs):
to_remove = []
for key in kwargs:
if key in [ 'buttontype', 'buttoncolor', 'buttonoutline',
'troughcolor', 'troughoutline',
'thumbcolor', 'thumbtype', 'thumboutline',
'command', 'orient']:
self._scroll_kwargs[key] = kwargs[key] # add to custom dict
to_remove.append(key)
for key in to_remove:
del kwargs[key]
return kwargs
def _get_colour(self, element):
if element in self._scroll_kwargs: # if element exists in settings
return self._scroll_kwargs[element]
if element.endswith('outline'): # if element is outline and wasn't in settings
return self._scroll_kwargs[element.replace('outline', 'color')] # fetch default for main element
def _width(self):
return self.winfo_width() - 2 # return width minus 2 pixes to ensure fit in canvas
def _height(self):
return self.winfo_height() - 2 # return height minus 2 pixes to ensure fit in canvas
def _resize(self, event):
width = self._width()
height = self._height()
if self.elements['button-1']: # exists
# delete element if vertical scrollbar and width changed
# or if horizontal and height changed, signals button needs to change
if (((self._oldwidth != width) and (self._scroll_kwargs['orient'] == 'vertical')) or
((self._oldheight != height) and (self._scroll_kwargs['orient'] == 'horizontal'))):
self.delete(self.elements['button-1'])
self.elements['button-1'] = None
if not self.elements['button-1']: # create
size = width if (self._scroll_kwargs['orient'] == 'vertical') else height
rect = (0,0,size, size)
fill = self._get_colour('buttoncolor')
outline = self._get_colour('buttonoutline')
if (self._scroll_kwargs['buttontype'] == 'round'):
self.elements['button-1'] = self.create_oval(rect, fill=fill, outline=outline, tag='button-1')
elif (self._scroll_kwargs['buttontype'] == 'square'):
self.elements['button-1'] = self.create_rectangle(rect, fill=fill, outline=outline, tag='button-1')
if self.elements['button-2']: # exists
coords = self.coords(self.elements['button-2'])
# delete element if vertical scrollbar and width changed
# or if horizontal and height changed, signals button needs to change
if (((self._oldwidth != width) and (self._scroll_kwargs['orient'] == 'vertical')) or
((self._oldheight != height) and (self._scroll_kwargs['orient'] == 'horizontal'))):
self.delete(self.elements['button-2'])
self.elements['button-2'] = None
# if vertical scrollbar and height changed button needs to move
elif ((self._oldheight != height) and (self._scroll_kwargs['orient'] == 'vertical')):
self.move(self.elements['button-2'], 0, height-coords[3])
# if horizontal scrollbar and width changed button needs to move
elif ((self._oldwidth != width) and (self._scroll_kwargs['orient'] == 'horizontal')):
self.move(self.elements['button-2'], width-coords[2], 0)
if not self.elements['button-2']: # create
if (self._scroll_kwargs['orient'] == 'vertical'):
rect = (0,height-width,width, height)
elif (self._scroll_kwargs['orient'] == 'horizontal'):
rect = (width-height,0,width, height)
fill = self._get_colour('buttoncolor')
outline = self._get_colour('buttonoutline')
if (self._scroll_kwargs['buttontype'] == 'round'):
self.elements['button-2'] = self.create_oval(rect, fill=fill, outline=outline, tag='button-2')
elif (self._scroll_kwargs['buttontype'] == 'square'):
self.elements['button-2'] = self.create_rectangle(rect, fill=fill, outline=outline, tag='button-2')
if self.elements['trough']: # exists
coords = self.coords(self.elements['trough'])
# delete element whenever width or height changes
if (self._oldwidth != width) or (self._oldheight != height):
self.delete(self.elements['trough'])
self.elements['trough'] = None
if not self.elements['trough']: # create
if (self._scroll_kwargs['orient'] == 'vertical'):
rect = (0, int(width/2), width, height-int(width/2))
elif (self._scroll_kwargs['orient'] == 'horizontal'):
rect = (int(height/2), 0, width-int(height/2), height)
fill = self._get_colour('troughcolor')
outline = self._get_colour('troughoutline')
self.elements['trough'] = self.create_rectangle(rect, fill=fill, outline=outline, tag='trough')
self.set(self._sb_start, self._sb_end) # hacky way to redraw thumb without moving it
self.tag_raise('thumb') # ensure thumb always on top of trough
self._oldwidth = width
self._oldheight = height
def _button_1(self, event):
command = self._scroll_kwargs['command']
if command:
command('scroll', -1, 'pages')
return 'break'
def _button_2(self, event):
command = self._scroll_kwargs['command']
if command:
command('scroll', 1, 'pages')
return 'break'
def _trough(self, event):
# print('trough: (%s, %s)' % (event.x, event.y))
width = self._width()
height = self._height()
coords = self.coords(self.elements['trough'])
if (self._scroll_kwargs['orient'] == 'vertical'):
trough_size = coords[3] - coords[1]
elif (self._scroll_kwargs['orient'] == 'horizontal'):
trough_size = coords[2] - coords[0]
# print('trough size: %s' % trough_size)
size = (self._sb_end - self._sb_start) / 1
if (self._scroll_kwargs['orient'] == 'vertical'):
thumbrange = height - width
elif (self._scroll_kwargs['orient'] == 'horizontal'):
thumbrange = width - height
thumbsize = int(thumbrange * size)
if (self._scroll_kwargs['orient'] == 'vertical'):
thumboffset = int(thumbrange * self._sb_start) + int(width/2)
elif (self._scroll_kwargs['orient'] == 'horizontal'):
thumboffset = int(thumbrange * self._sb_start) + int(height/2)
thumbpos = int(thumbrange * size / 2) + thumboffset
command = self._scroll_kwargs['command']
if command:
if (((self._scroll_kwargs['orient'] == 'vertical') and (event.y < thumbpos)) or
((self._scroll_kwargs['orient'] == 'horizontal') and (event.x < thumbpos))):
command('scroll', -1, 'pages')
elif (((self._scroll_kwargs['orient'] == 'vertical') and (event.y > thumbpos)) or
((self._scroll_kwargs['orient'] == 'horizontal') and (event.x > thumbpos))):
command('scroll', 1, 'pages')
return 'break'
def _thumb_press(self, event):
self._track = True
def _thumb_release(self, event):
self._track = False
def _thumb_track(self, event):
# print('track')
if self._track:
width = self._width()
height = self._height()
# print("window size: (%s, %s)" % (width, height))
size = (self._sb_end - self._sb_start) / 1
coords = self.coords(self.elements['trough'])
# print('trough coords: %s' % coords)
if (self._scroll_kwargs['orient'] == 'vertical'):
trough_size = coords[3] - coords[1]
thumbrange = height - width
elif (self._scroll_kwargs['orient'] == 'horizontal'):
trough_size = coords[2] - coords[0]
thumbrange = width - height
# print('trough size: %s' % trough_size)
thumbsize = int(thumbrange * size)
if (self._scroll_kwargs['orient'] == 'vertical'):
pos = max(min(trough_size, event.y - coords[1] - (thumbsize/2)), 0)
elif (self._scroll_kwargs['orient'] == 'horizontal'):
pos = max(min(trough_size, event.x - coords[0] - (thumbsize/2)), 0)
# print('pos: %s' % pos)
point = pos / trough_size
# print('point: %s' % point)
command = self._scroll_kwargs['command']
if command:
command('moveto', point)
return 'break'
def set(self, *args):
# print('set: %s' % str(args))
oldsize = (self._sb_end - self._sb_start) / 1
self._sb_start = float(args[0])
self._sb_end = float(args[1])
size = (self._sb_end - self._sb_start) / 1
width = self._width()
height = self._height()
if oldsize != size:
self.delete(self.elements['thumb'])
self.elements['thumb'] = None
if (self._scroll_kwargs['orient'] == 'vertical'):
thumbrange = height - width
thumboffset = int(thumbrange * self._sb_start) + int(width/2)
elif (self._scroll_kwargs['orient'] == 'horizontal'):
thumbrange = width - height
thumboffset = int(thumbrange * self._sb_start) + int(height/2)
thumbsize = int(thumbrange * size)
if not self.elements['thumb']: # create
if (self._scroll_kwargs['orient'] == 'vertical'):
rect = (0, thumboffset,width, thumbsize+thumboffset)
elif (self._scroll_kwargs['orient'] == 'horizontal'):
rect = (thumboffset, 0, thumbsize+thumboffset, height)
fill = self._get_colour('thumbcolor')
outline = self._get_colour('thumboutline')
if (self._scroll_kwargs['thumbtype'] == 'round'):
self.elements['thumb'] = self.create_oval(rect, fill=fill, outline=outline, tag='thumb')
elif (self._scroll_kwargs['thumbtype'] == 'rectangle'):
self.elements['thumb'] = self.create_rectangle(rect, fill=fill, outline=outline, tag='thumb')
else: # move
coords = self.coords(self.elements['thumb'])
if (self._scroll_kwargs['orient'] == 'vertical'):
if (thumboffset != coords[1]):
self.move(self.elements['thumb'], 0, thumboffset-coords[1])
elif (self._scroll_kwargs['orient'] == 'horizontal'):
if (thumboffset != coords[1]):
self.move(self.elements['thumb'], thumboffset-coords[0], 0)
return 'break'
if __name__ == '__main__':
root = tk.Tk()
root.grid_rowconfigure(1, weight=1)
root.grid_columnconfigure(1, weight=1)
root.grid_rowconfigure(3, weight=1)
root.grid_columnconfigure(3, weight=1)
lb = tk.Listbox(root)
lb.grid(column=1, row=1, sticky="nesw")
for num in range(0,100):
lb.insert('end', str(num)*100)
sby1 = MyScrollbar(root, width=50, command=lb.yview)
sby1.grid(column=2, row=1, sticky="nesw")
sby2 = MyScrollbar(root, width=50, command=lb.yview, buttontype='square', thumbtype='round')
sby2.grid(column=4, row=1, sticky="nesw")
sbx1 = MyScrollbar(root, height=50, command=lb.xview, orient='horizontal', buttoncolor='red', thumbcolor='orange', troughcolor='green')
sbx1.grid(column=1, row=2, sticky="nesw")
sbx2 = MyScrollbar(root, height=50, command=lb.xview, orient='horizontal', thumbtype='round')
sbx2.grid(column=1, row=4, sticky="nesw")
def x_set(*args):
sbx1.set(*args)
sbx2.set(*args)
def y_set(*args):
sby1.set(*args)
sby2.set(*args)
lb.configure(yscrollcommand=y_set, xscrollcommand=x_set)
root.mainloop()
so I've fixed the calculation to work out where the new scroll to position will be, and changed from binding on the thumb tag for the track and release events to binding on the whole canvas, so if the user scrolls quickly the binding will still release when the mouse is let go.
I've commented out the binding for when the cursor leaves the canvas so the behavior more closely mimics the existing scroll bar, but can be re enabled if you want it to stop scrolling if the mouse leaves the widget.
As for making two classes, the amended code above lets you use the orient
keyword so you can just drop this class (with styling changes) in place of the default scrollbar, as shown in the example at the bottom.