Issues with Python Tkinter: Frames within a Canvas - python

I'm trying to set up a scrollable series of Frames, so I've nested them into a Canvas. Below, I've included some sample code that demonstrates the problem.
However, I have three issues:
Frame c doesn't seem to expand horizontally to fill the canvas.
If I use multiple frames c, the canvas scrolls, but if I try to nest my FrameRows into a single frame c, the canvas no longer scrolls.
With multiple frames c, the last of the FrameRows is cut off.
Buttons "Left" and "Right" demonstrate the behavior I get when the buttons are not nested in a Canvas.
I'd prefer using the single Frame c and nesting all FrameRows in that, but I would need the scrolling to work properly for that.
import * from Tkinter
import FrameRow
root = Tk()
root.title("Testing")
containerFrame = Frame(root)
containerFrame.config(bg="red")
containerFrame.pack(side=TOP, fill=BOTH, expand=1)
# Frame showing proper behavior
a = Frame(containerFrame, bg="black")
a.pack(side=TOP, fill=X, expand=0)
btnLeft = Button(a)
btnLeft.config(text="LEFT")
btnLeft.pack(side=LEFT, fill=X, expand=1)
btnRight = Button(a)
btnRight.config(text="RIGHT")
btnRight.pack(side=RIGHT, fill=X, expand=0)
# Canvas
canvas = Canvas(containerFrame)
scrollbar = Scrollbar(containerFrame, orient=VERTICAL)
scrollbar.config(command=canvas.yview)
canvas.config(bg="blue", yscrollcommand=scrollbar.set)
scrollbar.pack(side=RIGHT, fill=Y)
canvas.pack(side=LEFT, fill=BOTH, expand=1)
# Multiple Frames within Canvas
frameRow = range(30)
c = range(30)
for r in xrange(0,30):
c[r] = Frame(canvas)
c[r].config(bg="green")
frameRow[r] = FrameRow.FrameRow()
frameRow[r].setFrame(c[r])
frameRow[r].setRow(r)
frameRow[r].createRow()
c[r].pack(side=TOP, fill=X, expand=1)
canvas.create_window(0, (r+1)*30, window=c[r], anchor="nw")
canvas.config(scrollregion = canvas.bbox(ALL))
# OR
# Single Frame within Canvas
##c = Frame(canvas)
##c.config(bg="green")
##
##frameRow = range(30)
##for r in xrange(0,30):
## frameRow[r] = FrameRow.FrameRow()
## frameRow[r].setFrame(c)
## frameRow[r].setRow(r)
## frameRow[r].createRow()
##
##c.pack(side=TOP, fill=X, expand=1)
##canvas.create_window(0, 0, window=c, anchor="nw")
root.mainloop()
The FrameRow class is defined as:
from Tkinter import *
class FrameRow():
_frame = "Default"
_row = 0
def setFrame(self, frame):
self._frame = frame
def setRow(self, row):
self._row = row
def createRow(self):
self.frameRow = Frame(self._frame)
self.frameRow.config(bg="yellow")
self.frameRow.pack(side=TOP, fill=X, expand=1)
self.btn1 = Button(self.frameRow)
self.btn1.config(text="Button "+str(self._row)+"A")
self.btn1.pack(side=LEFT, fill=X, expand=1)
self.btn2 = Button(self.frameRow)
self.btn2.config(text="Button "+str(self._row)+"B")
self.btn2.pack(side=RIGHT, anchor=E, fill=X, expand=0)
Is there something I'm missing in getting Frame(s) c to expand to the width of the canvas?
Am I doing something wrong with the scrolling and the single Frame c?
Are there any decent tutorials or examples that show how I should be doing this?
Thanks!

It looks like you are both packing the window in a canvas and creating a window object. I honestly have never done that but I don't think the packing does any good.
When you create a widget that is an object in a canvas, it will not expand to fill the canvas. What you'll need to do is create a binding to the <Configure> event of the canvas. This event will fire whenever the canvas changes size (and a few other times). You can then resize each frame to fit the width of the canvas.
Since you say you prefer using a single frame where you nest the other rows inside it, that is probably the easiest solution. But again, this single frame won't grow or shrink to fit the canvas, you'll have to do that with a <Configure> binding.
Make sure that you configure the scrollregion of the canvas after adding the frame to the canvas using create_window. It looks like you're forgetting to do that in the commented-out code, and that would definitely prevent the canvas from scrolling.

Related

How to add a slide bar in a table?

I've been creating an app where there are Clients that I can add to a table, the problem is, I need a scrollbar to scroll through all the clients since the app Height is limited and the clients aren't.
Using tkinter I found a way to create a "table" using Entry and grid, but what if I want to create 100 rows? they would be outside of the view, so that's why the need of a scrollbar.
For those of you who know Java, I wanted to create something similar to Jtable, it has a method to create row, delete row, and it generates automatically that scrollbar as soon as the JTable runs out of space.
I've tried to use TkTable from ttk and mess around with some properties, but I preferred how Entries look.
root = Tk()
root.geometry("1200x900")
for i in range(10):
e = Entry(relief=RIDGE)
e.grid(row=i, column=2, sticky=N)
root.mainloop()
I created a root = Tk() and used root to grid them.
You'll see 10 Entries on top of the other.
When a window contains many widgets, they might not all be visible. However, neither a window (Tk or Toplevel instance) nor a Entry are scrollable.
One solution to make the window content scrollable is to put all the widgets in a Frame, and then, embed this Frame in a Canvas using the create_window method.
from tkinter import *
root = Tk()
canvas = Canvas(root)
scroll_y = Scrollbar(root, orient="vertical", command=canvas.yview)
frame = Frame(canvas)
# group of widgets
for i in range(100):
e = Entry(frame, relief=RIDGE, width = 100)
e.grid(row=i, column=2, sticky=N)
# put the frame in the canvas
canvas.create_window(0, 0, anchor='nw', window=frame)
# make sure everything is displayed before configuring the scrollregion
canvas.update_idletasks()
canvas.configure(scrollregion=canvas.bbox('all'),
yscrollcommand=scroll_y.set)
canvas.pack(fill='both', expand=True, side='left')
scroll_y.pack(fill='y', side='right')
root.mainloop()
output:

TKinter scrollbar for middle of screen, supporting resizeable screen with top bar and bottom bar

I am trying to make an application that displays a grid in the middle of the screen surrounded by two bars, a top bar and a bottom bar, which contain buttons for the user to press. These buttons should be able to display no matter where the user scrolls to on the grid and should not be cut off if the window is resized. I am struggling to configure the scrollbar to track the right area and to have the grid fall off the screen when the window is resized. Here is my code so far:
from tkinter import *
def add_row(event):
input_row = Entry(grid_frame, bd=1, text="", bg="white", relief="solid")
input_row.grid(row=grid_frame.rows, sticky=N+S+E+W)
Grid.rowconfigure(grid_frame, grid_frame.rows, weight=1)
grid_frame.rows = grid_frame.rows + 1
class GridFrame(Frame):
rows = 0
def __init__(self, root):
Frame.__init__(self, root, bd=1)
root = Tk(className="Main screen")
root.minsize(408, 80)
# size to quarter of screen
w, h = root.winfo_screenwidth() / 2, root.winfo_screenheight() / 2
root.geometry("%dx%d+0+0" % (w, h))
# grid_frame will resize and bars will not
Grid.rowconfigure(root, 1, weight=1)
Grid.columnconfigure(root, 0, weight=1)
myframe = Frame(root, bd=4, relief="groove")
myframe.grid(row=1, sticky=N + W + S + E)
canvas = Canvas(myframe)
grid_frame = GridFrame(canvas)
grid_frame.pack(fill=BOTH, expand=True)
grid_frame.bind("<Button-1>", add_row)
scrollbar = Scrollbar(myframe, orient="vertical", command=canvas.yview)
canvas.configure(yscrollcommand=scrollbar.set)
scrollbar.pack(side=RIGHT, fill=Y)
canvas.pack(side=LEFT, fill=BOTH, expand=True)
topBar = Frame(root, grid_frame)
label = Label(topBar, text="Top Text")
label.pack()
topBar.grid(row=0, sticky=W+N+E+S)
bottomFrame = Frame(root, grid_frame)
label = Label(bottomFrame, text="Bottom Text")
label.pack()
bottomFrame.grid(row=2, sticky=E+S+W)
mainloop()
The scrollregion I want to track is the myframe/canvas/grid_frame combination I read to use from this post. The current functionality is that the scrollbar is never in an "active" state and rows added to the grid merely shrink the grid for it to fit within the display. To add a new row, click within the grid_frame region. Any help would be greatly appreciated! Here are some images of the current UI:
UI display with only a few rows
UI display with many more rows
There are two major problems with your code.
First, for the canvas to be able to scroll the inner frame, the inner frame must be a canvas object created with create_window. You're adding it to the canvas with pack, which means the canvas cannot scroll it.
To fix that, use create_window instead of pack:
canvas.create_window(0, 0, anchor="nw", window=grid_frame)
Second, you must reset the scrollregion attribute whenever the contents inside the canvas change. Normally this is done in a <Configure> event handler on the frame, but you can just as easily call it in your add_row function.
For example, add the following line to the end of add_row:
canvas.configure(scrollregion=canvas.bbox("all"))
With those two changes, the scrollbars will start to work as soon as the inner frame is taller than the canvas.
The above solves the problem of the inner window being able to scroll when you add items. In the specific example of this test program, you also have the problem that your binding is on the frame. At startup the frame has a size of 1x1 so it's a bit hard to click on. Moving the binding to the canvas will make this specific demo program work better.

Tkinter Dynamic scrollbar for a dynamic GUI not updating with GUI

This is related to a previous question:
Tkinter dynamically create widgets from button
At the time that I asked the previous question, I believed that it would be easy to add a scrollable frame around the dynamic GUI. Instead, I have had a single problem with the scrollbar not detecting the new frames and entry boxes after the button is pressed. How do I solve this without editing the ScrollFrame class much?
I know that the Scrollbarframe works with other widgets it is just that the dynamic component is causing issues. When I shrink the vertical size of the window past the original location of the createWidgets button, the scrollbar appears, but the scrollbar is not present for the rest of the dynamically created widgets. Does the canvas not detect that the vertical size of the frame increases with a button press?
Note: I am aware that wildcard imports are awful. I'm just using one for the example
from tkinter import *
class AutoScrollbar(Scrollbar):
# A scrollbar that hides itself if it's not needed.
# Only works if you use the grid geometry manager!
def set(self, lo, hi):
if float(lo) <= 0.0 and float(hi) >= 1.0:
# grid_remove is currently missing from Tkinter!
self.tk.call("grid", "remove", self)
else:
self.grid()
Scrollbar.set(self, lo, hi)
def pack(self, **kw):
raise TclError("cannot use pack with this widget")
def place(self, **kw):
raise TclError("cannot use place with this widget")
class ScrollFrame:
def __init__(self, master):
self.vscrollbar = AutoScrollbar(master)
self.vscrollbar.grid(row=0, column=1, sticky=N+S)
self.hscrollbar = AutoScrollbar(master, orient=HORIZONTAL)
self.hscrollbar.grid(row=1, column=0, sticky=E+W)
self.canvas = Canvas(master, yscrollcommand=self.vscrollbar.set,
xscrollcommand=self.hscrollbar.set)
self.canvas.grid(row=0, column=0, sticky=N+S+E+W)
self.vscrollbar.config(command=self.canvas.yview)
self.hscrollbar.config(command=self.canvas.xview)
# make the canvas expandable
master.grid_rowconfigure(0, weight=1)
master.grid_columnconfigure(0, weight=1)
# create frame inside canvas
self.frame = Frame(self.canvas)
self.frame.rowconfigure(1, weight=1)
self.frame.columnconfigure(1, weight=1)
def update(self):
self.canvas.create_window(0, 0, anchor=NW, window=self.frame)
self.frame.update_idletasks()
self.canvas.config(scrollregion=self.canvas.bbox("all"))
if self.frame.winfo_reqwidth() != self.canvas.winfo_width():
# update the canvas's width to fit the inner frame
self.canvas.config(width = self.frame.winfo_reqwidth())
if self.frame.winfo_reqheight() != self.canvas.winfo_height():
# update the canvas's width to fit the inner frame
self.canvas.config(height = self.frame.winfo_reqheight())
frames = []
widgets = []
def createwidgets():
global widgetNames
global frameNames
frame = Frame(o.frame, borderwidth=2, relief="groove")
frames.append(frame)
frame.pack(side="top", fill="x")
widget = Entry(frame)
widgets.append(widget)
widget.pack(side="left")
root = Tk()
o = ScrollFrame(root)
label = Label(o.frame, text = "test")
label1 = Label(o.frame, text = "test")
label2 = Label(o.frame, text = "test")
label3 = Label(o.frame, text = "test")
label.pack()
label1.pack()
label2.pack()
label3.pack()
createWidgetButton = Button(o.frame, text="createWidgets",
command=createwidgets)
createWidgetButton.pack(side="bottom", fill="x")
o.update()
root.mainloop()
This is what the window would look like if it was fully expanded
If I were to shrink the window, it should immediately create a vertical scrollbar because that would cover a widget. However, the scrollbar acts like the program was still in its initial state.
Incorrect Scrollbar(at the moment that the scrollbar appears)
You need to make sure that you update the canvas scrollregion whenever you add widgets to the inner frame. The most common solution is to bind to the frame's <Configure> event, which will fire whenever the frame changes size.
In ScrollFrame.__init__ add the following line after you create the frame:
self.frame.bind("<Configure>", self.reset_scrollregion)
Then, add this function to ScrollFrame:
def reset_scrollregion(self, event):
self.canvas.configure(scrollregion=self.canvas.bbox("all")

Textbox not expanding with containing frame - TKinter

I'm building an application that provides viewports for an internal data file. The files are somewhat complex, so I've created three sub-windows that handle different aspects of the file. The upper left provides an outline of the different sections, the upper right provides a series of text widgets containing errors found in the data file, and the lower provides a view of the datafile itself. To facilitate all of this, I wrote a small class that serves as a frame for each of these sections and can be populated with labels, textboxes, etc. (Code below.)
The problem I'm running into is that the text widgets in the upper right and lower sections do not expand with their containing frame. Based on various searches of effbot.org, Stackoverflow, and others, I think I have the settings correct, but obviously something is wrong. If I enlarge the main window, each section adapts as it should, but the text widgets don't expand left to right to fill the new subwindow dimensions.
Any tips are greatly appreciated.
Here's the class that provides functionality for the subwindows:
import Tkinter as tk
class ScrollingChildFrame(tk.Frame):
'''
A Tkinter class creating a scrollable window that can be used
in a docked multiple document interface form. The window created here
allows addition of widgets to create scrolling tables (spreadsheet like),
groups of text fields, etc.
'''
def __init__(self, root):
self.count = 0
tk.Frame.__init__(self)
self.root = root
self.canvas = tk.Canvas(self, height=self.winfo_height(), width=self.winfo_width() )
self.canvas.grid(row=0, column=0, sticky='nsew')
self.vsb = tk.Scrollbar(self, orient='vertical', command=self.canvas.yview)
self.vsb.grid(row=0,column=1,sticky='ns')
self.hsb = tk.Scrollbar(self, orient='horizontal', command=self.canvas.xview)
self.hsb.grid(row=1,column=0,sticky='ew')
self.intframe = tk.Frame(self.canvas)
self.intframe.config(height=self.winfo_height(), width=self.winfo_width())
self.canvas.configure(yscrollcommand=self.vsb.set, xscrollcommand=self.hsb.set)
self.canvas.create_window(0, 0, window=self.intframe, anchor='nw')
#set event bindings
self.bind('<Configure>', self.OnFrameConfigure)
self.intframe.bind('<Configure>', self.OnIntFrameConfigure)
def OnFrameConfigure(self, event=None):
'''
adjust canvas when main frame adjusts
'''
self.canvas.configure(width=event.width - self.vsb.winfo_width()-2,
height=event.height - self.hsb.winfo_height()-2)
def OnIntFrameConfigure(self, event=None):
'''
adjust the scrolling window when the internal frame is adjusted
'''
self.canvas.configure(scrollregion=self.canvas.bbox(tk.ALL))
Here's an example of how I'm using it with textboxes that don't expand:
import Tkinter as tk
from scrollingchildframe import *
class Vis_GUI:
'''
The main GUI class
'''
def __init__(self):
#tkinter stuff
self.root = tk.Tk()
self.root.geometry('500x500')
self.create_frames()
self.root.mainloop()
def create_frames(self):
'''
Build the GUI frames
'''
self.root.columnconfigure(0,weight=1)
self.root.columnconfigure(1,weight=3)
self.root.rowconfigure(0,weight=1)
self.root.rowconfigure(1,weight=3)
#data blocks
self.block_frame = ScrollingChildFrame(self.root)
self.block_frame.config(height=200, width=200)
##error list
self.error_frame = ScrollingChildFrame(self.root)
self.error_frame.config(height=200, width=300)
##data
self.data_frame = ScrollingChildFrame(self.root)
self.data_frame.config(height=300, width=500)
##populate with empty cells
self.PopulateEmpty()
##place them on the grid
self.block_frame.grid(row=0, column=0, padx=2, pady=2, sticky='nsew')
self.error_frame.grid(row=0,column=1, padx=2, pady=2, sticky='nsew')
self.data_frame.grid(row=1, column=0, columnspan=2, padx=2,pady=2, sticky='nsew')
def PopulateEmpty(self):
'''
Populate the frames with empty contents so it doesn't look quite so empty.
'''
z = tk.Text(self.data_frame.intframe)
z.insert(tk.INSERT, 'blah\nblah\nblah')
height = float(z.index(tk.END))
z.config( height=height, state=tk.DISABLED, wrap=tk.NONE)
z.pack(anchor='nw', expand=1, fill=tk.X)
z = tk.Text(self.error_frame.intframe, height=1)
z.pack(anchor='w', expand = 1, fill=tk.X)
z = tk.Label(self.block_frame.intframe, text = 'No file open')
z.pack(anchor='w')
if (__name__=="__main__"):
wv = Vis_GUI()
The Frame also has to have expand and fill options set (and you will have to check on what ScrollingChildFrame does-and this is not a complaint about incomplete code, just pointing out the next step). Using just pack() for the Frame in the following code will not allow it to expand. You can uncomment it and comment the other pack if you want to see the difference.
try:
import Tkinter as tk ## Python 2.x
except ImportError:
import tkinter as tk ## Python 3.x
top=tk.Tk()
## use separate frame instead of top
fr=tk.Frame(top)
##fr.pack() ## does not expand
fr.pack(anchor='nw', expand=1, fill=tk.X)
z = tk.Text(fr)
insert_text="%s" % ("blah"*25) + 'blah\nblah\nblah'
z.insert(tk.INSERT, insert_text)
height = float(z.index(tk.END))
z.config( height=height, state=tk.DISABLED, wrap=tk.NONE)
z.pack(anchor='nw', expand=1, fill=tk.X)
top.mainloop()

Python tkinter: issues resizing frames

I'm trying to resize a window in my GUI but one of my frames is getting left out and I'm not sure why. The window resizes fine horizontally, but when I try to resize vertically the frame with the button disappears. This is my first GUI so I'm sure there is something I'm missing...
from Tkinter import *
from ttk import *
class GUI(Frame):
def __init__(self, root):
Frame.__init__(self, root)
self.root = root
lbFrame = Frame(self.root)
nbFrame = Frame(self.root)
self.note = Notebook(nbFrame)
self.note.pack(fill=BOTH, expand=YES)
lbFrame.pack(side=LEFT, fill=BOTH, expand=YES)
nbFrame.pack(side=RIGHT, fill=BOTH, expand=YES)
self.make_file_viewer()
# Label
lblabel = Label(lbFrame, text='Files', background='#E8E8E8')
lblabel.pack(side=TOP, expand=YES, padx=10, pady=10)
# Listbox
self.lb = Listbox(lbFrame, height=49, borderwidth=0, font=('Purisa', 11), selectmode=EXTENDED)
self.lb.pack(side=BOTTOM, expand=YES, padx=10, pady=10)
def make_file_viewer(self):
fvwr = Frame(self.note)
dataFrm = Frame(fvwr)
btnFrm = Frame(fvwr)
dataFrm.pack(side=TOP, fill=BOTH, expand=YES)
btnFrm.pack(side=BOTTOM, fill=BOTH, expand=YES)
fvwr.config(borderwidth=2)
self.note.add(fvwr, text='File View')
# Label
self.lbl_fvwr_search = Label(dataFrm, text='Search Hits\t0', justify=LEFT)
self.lbl_fvwr_search.pack(side=TOP, anchor=W, expand=YES)
# Scrollbar
scrollbar_fvwr = Scrollbar(dataFrm)
scrollbar_fvwr.pack(side=RIGHT, fill=Y, expand=YES)
# Textbox
self.outputPanel_fvwr_text = Text(dataFrm, wrap='word', height=40, width=115, yscrollcommand=scrollbar_fvwr.set)
self.outputPanel_fvwr_text.pack(side=LEFT, fill=BOTH, expand=YES)
scrollbar_fvwr.config(command=self.outputPanel_fvwr_text.yview)
# Start button
viewBtn = Button(btnFrm, text='Start', width=8)
viewBtn.pack(anchor=W, expand=YES)
if __name__ == '__main__':
root = Tk()
app = GUI(root)
root.mainloop()
The absolute best thing you can do is to start over, and do your layout step-by-step. Start by creating the main areas, and make sure they resize properly. In your case, create the left and right sides. Again, get those two sides resizing properly with respect to each other.
Once you are done, focus on one section. Since you know the main section resizes properly, you only need to focus on the elements within that particular side. Again, break it down into pieces, and get those pieces working before tackling any widgets inside the main pieces.
When you do your layout this way, it's much easier to get the whole GUI working right, because you aren't trying to juggle the behavior of a half dozen widgets at once.
In your specific case, the root of the problem is that you have expand=YES for just about everything. As a general rule of thumb, you only want to set that to YES for one widget in an given parent window. For example, in your main window you want the right to expand but not the left (I'm guessing), and in the right window you want the text widget to expand but not the other widgets.
Set expand=NO for scrollbar_fvwr, self.lbl_fvwr_search, and btnFrm to get the right side to resize properly. For the left side, add fill=BOTH for self.lb, and expand=NONE for lblabel.

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