Tkinter not updating in Windows OS when scrolling too fast - windows

Question

As seen in the example above, a mixture of the Label objects on the left column or Entry objects on the right column are not shown when scrolling too fast.
If I click on the scrollbar and drag quickly it can look as bad as this. If I use the wheel on the mouse to scroll slowly it is typically fine, though sometimes a line will get missed no matter how slowly I scroll. For reference, it seems to always be the same line(s) that do not show when scrolling slowly.
Changing tabs back and forth causes everything to draw properly again. On Linux, everything works perfectly. But this needs to work on Windows as well.
Not sure if it matters, but each line is a Label and Entry inside of a Frame inside of a Canvas that, along with a Scrollbar, is inside of a Frame. Each of those top Frames is a "page" in a Notebook to provide the tabs shown on top.
And finally some questions. Is there a button I can add to force this to redraw without destroying and recreating it? Or possibly something I can add when creating these objects to force them to redraw when moved?
Sample code upon request:
#!/usr/bin/env python3
from tkinter import *
from tkinter import ttk
from tkinter.scrolledtext import ScrolledText
class WriteableEntry(Label):
def __init__(self, name, value, *args, **kwargs):
#~ self.ip = ip
#~ self.ping_results = []
super(WriteableEntry, self).__init__(*args, **kwargs)
self.label = name
self.init_value = value
self.written_value = ''
self.field_name = Label(self, justify="left", text=name, width=25)
self.field_value = Entry(self, justify='left', width=60)
self.field_value.insert(END, value)
self.field_name.pack(side=LEFT)
self.field_value.pack(side=LEFT)
class InfoFrame(Frame):
def __init__(self, *args, **kwargs):
super(InfoFrame, self).__init__(*args, **kwargs)
self.nb_frame = Frame(self, height=300, width=730)
self.nb_frame.pack_propagate(False)
self.nb = ttk.Notebook(self.nb_frame)
self.nb.pressed_index = None
filler = {}
for x in range(0, 3):
for y in ('a', 'b', 'c', 'd', 'e', 'f', 'g'):
filler.update({"out%d_%s" % (x, y):"nada"})
self.example_dict = {'A':filler, 'B':filler, 'C':filler}
print("E_D:\n", self.example_dict)
for page in sorted(self.example_dict):
print("page:\t", page)
entry_count = len(self.example_dict[page])
# # ## Make new_page to put in nb
new_page = Frame(self.nb)
new_page.pack(fill=BOTH, expand=True)
# # ## Make canvas to put in that new_page
canvas = Canvas(new_page)
scroll = Scrollbar(new_page, command=canvas.yview)
## Orig *27
canvas.config(yscrollcommand=scroll.set, scrollregion=(0,120,120,entry_count * 35))
canvas.pack(side=LEFT, fill=BOTH, expand=True)
scroll.pack(side=RIGHT, fill=Y)
# # ## Make a frame to put in that canvas
canvas_frame = Frame(canvas, bg='white', width=50, height=50)
## Orig +12 *10
canvas.create_window(345, (entry_count + 12) * 13, window=canvas_frame)
for value in sorted(self.example_dict[page]):
print("value:\t", value)
writeable_entry = WriteableEntry(value, self.example_dict[page][value], master=canvas_frame)
writeable_entry.pack(side=TOP)
self.nb.add(new_page, text=page)
self.nb.pack(side=TOP, expand=True, fill="both")
self.nb_frame.pack(side=RIGHT, expand=True, fill=BOTH)
class IPLabel(LabelFrame):
def __init__(self, *args, **kwargs):
super(IPLabel, self).__init__(*args, **kwargs)
self.info_frame = InfoFrame(master=self)
self.info_frame.grid(row=1, columnspan=2, sticky=E + W)
class AvailableApplication(Frame):
def __init__(self, master):
super(AvailableApplication, self).__init__(master)
#~ self.ips = ips
self.grid()
self.grid_propagate(True)
self.ip_widgets = []
self.createWidgets()
def createWidgets(self):
self.ip_frame = Frame(self)
self.ip_widgets = []
ip_widget = IPLabel(master=self.ip_frame)
ip_widget.grid(row=0, column=1, columnspan=4, sticky=E + W)
self.ip_widgets.append(ip_widget)
self.ip_frame.grid(row=1, column=0, columnspan=8)
self.ip_frame.grid_propagate(True)
if __name__ == "__main__":
root = Tk()
root.title("Example Script")
app = AvailableApplication(root)
app.mainloop()
root.destroy()

Answer 1

The main problem is the WriteableEntry. It is not a tk.Label. You can't have sub widgets (a tk.Label and a tk.Entry) of a tk.Label. You also have the wrong layout manager for this work. Maybe also because of the wrong sub widget use. You rely on the wrap behavior of the pack manager. Don't. Use the grid() manager.
For some reason tab C is not visible but that is another problem.
Using Ctrl-Tab I found that there is a third tab but the tab text was the empty string. Adding the tab with
self.nb.add(new_page, text="P"+page)
Made it better visible. I have no idea why the tab name "C" has a special meaning for tkinter
The only possible way to kill the App and window is by using the Close button. So why do you destroy the root window? It is already destroyed.
#!/usr/bin/env python3
from tkinter import *
from tkinter import ttk
from tkinter.scrolledtext import ScrolledText
class WriteableEntry(object):
def __init__(self, name, value, *args, **kwargs):
#~ self.ip = ip
#~ self.ping_results = []
#super(WriteableEntry, self).__init__(*args, **kwargs)
master = kwargs['master']
row = kwargs['row']
self.label = name
self.init_value = value
self.written_value = ''
self.field_name = Label(master, justify="left", text=name, width=25)
self.field_value = Entry(master, justify='left', width=60)
self.field_value.insert(END, value)
self.field_name.grid(row=row, column=0)
self.field_value.grid(row=row, column=1)
class InfoFrame(Frame):
def __init__(self, *args, **kwargs):
super(InfoFrame, self).__init__(*args, **kwargs)
self.nb_frame = Frame(self, height=300, width=730)
self.nb_frame.pack_propagate(False)
self.nb = ttk.Notebook(self.nb_frame)
self.nb.pressed_index = None
filler = {}
for x in range(0, 3):
for y in ('a', 'b', 'c', 'd', 'e', 'f', 'g'):
filler.update({"out%d_%s" % (x, y):"nada"})
self.example_dict = {'A':filler, 'B':filler, 'C':filler}
print("E_D:\n", self.example_dict)
for page in sorted(self.example_dict):
print("page:\t", page)
entry_count = len(self.example_dict[page])
# # ## Make new_page to put in nb
new_page = Frame(self.nb)
new_page.pack(fill=BOTH, expand=True)
# # ## Make canvas to put in that new_page
canvas = Canvas(new_page)
scroll = Scrollbar(new_page, command=canvas.yview)
## Orig *27
canvas.config(yscrollcommand=scroll.set, scrollregion=(0,120,120,entry_count * 35))
canvas.pack(side=LEFT, fill=BOTH, expand=True)
scroll.pack(side=RIGHT, fill=Y)
# # ## Make a frame to put in that canvas
canvas_frame = Frame(canvas, bg='white', width=50, height=50)
## Orig +12 *10
canvas.create_window(345, (entry_count + 12) * 13, window=canvas_frame)
for row, value in enumerate(sorted(self.example_dict[page])):
print("value:\t", value)
writeable_entry = WriteableEntry(value, self.example_dict[page][value], master=canvas_frame, row=row)
#writeable_entry.pack(side=TOP)
self.nb.add(new_page, text="P"+page)
self.nb.pack(side=TOP, expand=True, fill="both")
self.nb_frame.pack(side=RIGHT, expand=True, fill=BOTH)
class IPLabel(LabelFrame):
def __init__(self, *args, **kwargs):
super(IPLabel, self).__init__(*args, **kwargs)
self.info_frame = InfoFrame(master=self)
self.info_frame.grid(row=1, columnspan=2, sticky=E + W)
class AvailableApplication(Frame):
def __init__(self, master):
super(AvailableApplication, self).__init__(master)
#~ self.ips = ips
self.grid()
self.grid_propagate(True)
self.ip_widgets = []
self.createWidgets()
def createWidgets(self):
self.ip_frame = Frame(self)
self.ip_widgets = []
ip_widget = IPLabel(master=self.ip_frame)
ip_widget.grid(row=0, column=1, columnspan=4, sticky=E + W)
self.ip_widgets.append(ip_widget)
self.ip_frame.grid(row=1, column=0, columnspan=8)
self.ip_frame.grid_propagate(True)
if __name__ == "__main__":
root = Tk()
root.title("Example Script")
app = AvailableApplication(root)
app.mainloop()
#root.destroy()