I am trying to delete a widget that has the name of a string but I cant find how to do it. This is what I have done so far but I cant get my head around that. I want to be able to select the name of the widget that I want to get deleted. any help would be useful
and this is the code that i have made so far
lasthover = "button1"
def dlt():
for widget in frm.winfo_children():
if widget == lasthover:
widget.destroy()
You can set the widget name using option name when creating the widget and then destroy it using the given name.
Below is an example:
import tkinter as tk
root = tk.Tk()
frm = tk.Frame(root)
frm.pack()
# create buttons with name button1, button2, etc
for i in range(1, 10):
name = f"button{i}"
tk.Button(frm, text=name, name=name).pack(side="left")
lasthover = "button1"
def dlt():
for widget in frm.winfo_children():
if widget._name == lasthover:
widget.destroy()
tk.Button(root, text="Destroy Button", command=dlt).pack()
root.mainloop()
ok, so here is my solution (using classes), this is how I did it in one of my projects (similarly), this also may raise a lot of questions so feel free to ask:
from tkinter import Tk, Button
root = Tk()
removable_widget_dict = {}
class RemovableWidget(Button):
def __init__(self, title, parent, key):
Button.__init__(self, parent)
self.parent = parent
self.title = title
self.key = key
self.button = Button(self.parent, text=self.title)
self.button.pack()
def delete(self):
global removable_widget_dict
self.button.destroy()
del removable_widget_dict[self.key]
print(removable_widget_dict)
for i in range(10):
key = f'item{i}'
removable_widget_dict[key] = RemovableWidget(f'Button {i}', root, key)
print(removable_widget_dict)
for key in removable_widget_dict.keys():
if key == 'item5':
removable_widget_dict[key].delete()
break
root.mainloop()
in simple terms: there is the class that will be the removable widgets, each time an instance of that class is created in the for loop, it is saved in dictionary. when deleting You match Your criteria with dictionary key and execute a function to delete the widget and remove it from the dictionary
Related
I have created a custom widget for tkinter that lays out 5 buttons. The widget works beautifully for the most part. The problem is that I cannot figure out how to pass the button that the user presses in the widget to the main application. The custom widget stores the last button pressed in a variable, but I cannot figure out how to make the main application see that it has been changed without resorting to binding a button release event to root. I would like to try to build out this custom widget further, and I want it to work without having to do some messy hacks. Ideally, in the example below, when a button is pressed, the label should change to reflect the button pressed. For example, if the user clicks the "2" button, the label should change to "2 X 2 = 4". How can I pass the text on the button directly to the main application for use? Hopefully, I am making it clear enough. I want to be able to get the value from the widget just like any other tkinter widget using a .get() method. Here is the code that I am using:
import tkinter as tk
from tkinter import ttk
class ButtonBar(tk.Frame):
def __init__(self, parent, width=5, btnLabels=''):
tk.Frame.__init__(self, parent)
self.btnLabels = []
self.btnNames = []
self.setLabels(btnLabels)
self.selButton = None
self.display()
def getPressedBtn(self,t):
"""
This method will return the text on the button.
"""
self.selButton = t
print(t)
def createBtnNames(self):
"""
This method will create the button names for each button. The button
name will be returned when getPressedBtn() is called.
"""
for i in range(0,5):
self.btnNames.append(self.btnLabels[i])
def display(self):
"""
This method is called after all options have been set. It will display
the ButtonBar instance.
"""
self.clear()
for i in range(len(self.btnLabels)):
self.btn = ttk.Button(self, text=self.btnLabels[i], command=lambda t=self.btnNames[i]: self.getPressedBtn(t))
self.btn.grid(row=0, column=i)
def setLabels(self, labelList):
if labelList == '':
self.btnLabels = ['1', '2', '3', '4', '5']
self.createBtnNames()
else:
btnLabelStr = list(map(str, labelList))
labelsLen = len(btnLabelStr)
def clear(self):
"""
This method clears the ButtonBar of its data.
"""
for item in self.winfo_children():
item.destroy()
root = tk.Tk()
def getButtonClicked(event):
global selBtn
print(event)
if example.winfo_exists():
selBtn = example.selButton
answer = int(selBtn) * 2
myLabel.config(text='2 X ' + selBtn + ' = ' + str(answer))
tabLayout = ttk.Notebook(root)
tabLayout.pack(fill='both')
vmTab = tk.Frame(tabLayout)
myLabel = tk.Label(vmTab, text='2 X 0 = 0', width=50, height=10)
myLabel.pack()
vmTab.pack(fill='both')
tabLayout.add(vmTab, text='Volume Movers')
# Create the ButtonBar.
example = ButtonBar(vmTab)
selBtn = None
example.pack()
lbl = tk.Label(root, text='')
root.mainloop()
I have looked at some other posts on stackoverflow. This one creating a custom widget in tkinter was very helpful, but it didn't address the button issue. I though this Subclassing with Tkinter might help. I didn't understand the If I bind the event using root.bind("<ButtonRelease-1>", getButtonClicked), then the widget works fine. Is there any other way to do it though?
I'd say that you have made the code more complex than it should be, you really just need to create the buttons and give them some callback that is passed as an argument. And that callback should take at least one argument which would be the text that would be on the button which will be also passed to that callback.
import tkinter as tk
from tkinter import ttk
class ButtonBar(tk.Frame):
def __init__(self, master, values: list, command=None):
tk.Frame.__init__(self, master)
for col, text in enumerate(values):
btn = ttk.Button(self, text=text)
if command is not None:
btn.config(command=lambda t=text: command(t))
btn.grid(row=0, column=col, sticky='news')
def change_label(val):
res = 2 * int(val)
new_text = f'2 X {val} = {res}'
my_label.config(text=new_text)
root = tk.Tk()
my_label = tk.Label(root, text='2 X 0 = 0')
my_label.pack(pady=100)
texts = ['1', '2', '3', '4', '5']
example = ButtonBar(root, values=texts, command=change_label)
example.pack()
root.mainloop()
You can also base the buttons on a list of values so that you can specify any values and it will create buttons that have that text on them and pressing them will call the given function with an argument of their text. That way you can use it as really any other widget, it would require the master, some values (text) and a command. Then you would just create that callback, which will take that one argument and then change the label accordingly. (I also removed all the notebook stuff, but I am just showing how you can achieve what you asked for)
Also:
I strongly suggest following PEP 8 - Style Guide for Python Code. Function and variable names should be in snake_case, class names in CapitalCase. Have two blank lines around function and class declarations. Object method definitions have one blank line around them.
I'm trying to clear a tkinter window completely. However, I need a way to clear every widget on the window all at once without using pack.forget().
You could use a simple recursive loop to list all the children wigets of your main window :
def all_children (window) :
_list = window.winfo_children()
for item in _list :
if item.winfo_children() :
_list.extend(item.winfo_children())
return _list
Then just use this list :
widget_list = all_children(window)
for item in widget_list:
item.pack_forget()
What you need to do is set a frame to your main window and place everything that is to be cleared out at some point inside that frame. Then you simply do frame_name.destroy()
The following example has a button that creates a frame with several label widgets and a button.
The button calls a method that will destroy the frame and everything in it.
Then you can create the frame again with the first button.
Let me know if you have any question:
import tkinter as tk
class ExampleApp(tk.Frame):
def __init__(self, master):
tk.Frame.__init__(self, master)
self.master = master
self.some_frame = None
tk.Button(self.master, text="Create new frame with widgets!", command = self.create_stuff).pack()
def create_stuff(self):
if self.some_frame == None:
self.some_frame = tk.Frame(self.master)
self.some_frame.pack()
for i in range(5):
tk.Label(self.some_frame, text = "This is label {}!".format(i+1)).pack()
tk.Button(self.some_frame, text="Destroy all widgets in this frame!",
command= self.destroy_some_frame).pack()
def destroy_some_frame(self):
self.some_frame.destroy()
self.some_frame = None
root = tk.Tk()
my_example = ExampleApp(root)
root.mainloop()
You can use destroy method for each widget for example if it's a button you write btn1.destroy() and do it for all widgets. The forget method isn't recommended for it only remove the widgets from appearance.
I am creating a simple program using Tkinter. I want a function to be called every time xview property of entry changes. But there doesn't seem to be an event like this, at least not one that I can find.
The <Configure> event fires only on resize, which I already handled, but it doesn't fire when actual value I'm tracking changes in a different way, such as the user dragging his mouse to see the end of the entry.
Here is the code:
import Tkinter as Tk
import tkFileDialog
root = Tk.Tk()
class RepositoryFolderFrame(Tk.Frame):
def __init__(self, root):
Tk.Frame.__init__(self, root)
self.build_gui()
self.set_entry_text("Searching...")
#root.after(0, self.find_repo)
self.prev_entry_index = len(self.entry.get())
root.bind("<Configure>", self.on_entry_resize)
#self.entry.bind(???, self.on_entry_change)
#self.entry.bind("<Configure>", self.on_entry_change)
def on_entry_resize(self, event):
cur_entry_index = self.entry.xview()[1]
if cur_entry_index != self.prev_entry_index:
self.entry.xview(self.prev_entry_index)
def on_entry_change(self, event):
# This should be called when xview changes...
cur_entry_index = self.entry.xview()[1]
self.prev_entry_index = cur_entry_index
def set_entry_text(self, text):
self.entry_text.set(text)
self.entry.xview("end")
def build_gui(self):
label = Tk.Label(self, text = "Repository folder:")
label.pack(side = Tk.LEFT)
self.label = label
entry_text = Tk.StringVar()
self.entry_text = entry_text
entry = Tk.Entry(self, width = 50, textvariable = entry_text)
entry.configure(state = 'readonly')
entry.pack(side = Tk.LEFT, fill = Tk.X, expand = 1)
self.entry = entry
button = Tk.Button(self, text = "Browse...")
button.pack(side = Tk.LEFT)
self.button = button
repo_frame = RepositoryFolderFrame(root)
repo_frame.pack(fill = Tk.X, expand = 1)
root.mainloop()
There is no mechanism for getting notified when the xview changes. There are ways to do it by modifying the underlying tcl code, but it's much more difficult than it's worth.
A simple solution is to write a function that polls the xview every few hundred milliseconds. It can keep track of the most recent xview, compare it to the current, and if it has changed it can fire off a custom event (eg: <<XviewChanged>>) which you can bind to.
It would look something like this:
class RepositoryFolderFrame(Tk.Frame):
def __init__(self, root):
...
self.entry.bind("<<XviewChanged>>", self.on_entry_change)
# keep a cache of previous xviews. A dictionary is
# used in case you want to do this for more than
self._xview = {}
self.watch_xview(self.entry)
def watch_xview(self, widget):
xview = widget.xview()
prev_xview = self._xview.get(widget, "")
self._xview[widget] = xview
if xview != prev_xview:
widget.event_generate("<<XviewChanged>>")
widget.after(100, self.watch_xview, widget)
You'll need to modify that for the edge case that the entry widget is destroyed, though you can handle that with a simple try around the code. This should be suitably performant, though you might need to verify that if you have literally hundreds of entry widgets.
I was playing around with some Tkinter code that I found online:
from Tkinter import *
class ScrolledList(Frame):
def __init__(self, options, parent=None):
Frame.__init__(self, parent)
self.pack(expand=YES, fill=BOTH)
self.makeWidgets(options)
def handleList(self, event):
index = self.listbox.curselection()
label = self.listbox.get(index)
self.runCommand(label)
def makeWidgets(self, options):
sbar = Scrollbar(self)
list = Listbox(self, relief=SUNKEN)
sbar.config(command=list.yview)
list.config(yscrollcommand=sbar.set)
sbar.pack(side=RIGHT, fill=Y)
list.pack(side=LEFT, expand=YES, fill=BOTH)
pos = 0
for label in options:
list.insert(pos, label)
pos = pos + 1
list.bind('<Double-1>', self.handleList)
self.listbox = list
def runCommand(self, selection):
print 'You selected:', selection
if __name__ == '__main__':
options = map((lambda x: 'Lumberjack-' + str(x)), range(20))
ScrolledList(options).mainloop()
My question is: where is the frame created? I don't see anything like:
F1 = Tkinter.Frame()
Say if I wanted to add a label it would be:
label = Tkinter.Label(F1)
I'm looking into being able to add labels, and destroy the whole window when done (most likely add frame.destroy() line after print selection but I don't know what to address in that code).
Frames don't have titles; this works because Tkinter automagically creates a Tk instance the first time any widget is created and Tkinter detects that the root window hasn't been created yet (HT #BryanOakley). If you want to alter the window title, explicitly create a Tk instance and provide it as the parent to the ScrolledList:
if __name__ == '__main__':
options = map((lambda x: 'Lumberjack-' + str(x)), range(20))
app = Tk()
app.title('Demo')
ScrolledList(options, parent=app)
app.mainloop()
In many ways this is better, as it's easier to understand what's going on.
my question is were [sic] is the frame created?
A ScrolledList is a Frame, that's the whole point of inheritance (class ScrolledList(Frame): means "define a new class ScrolledList that inherits its behaviour from Frame"). So the frame is created by ScrolledList(...).
As #jonrsharpe points out, a ScrolledList is a Frame because the class is derived from it. The base Frame class is initialized in the first line of the ScrolledList.__init__() method:
class ScrolledList(Frame):
def __init__(self, options, parent=None):
Frame.__init__(self, parent) # <- calls base class constructor
...
Also, frames don't have a titles, so the closest way to have one is to add it to the window the frame is inside of. This can be done by explicitly creating the root window so you have a reference to it, use that to set its title, and then pass the window explicitly as the ScrolledList's parent:
if __name__ == '__main__':
root = Tk()
root.title('MyTitle')
root.minsize(200, 200) # also added so title is visible
options = map((lambda x: 'Lumberjack-' + str(x)), range(20))
ScrolledList(options, root) # <- Passes root window as the parent
root.mainloop()
i am going to create an tkinter gui app, and i know how i want it to look. but after playing around with tkinter, i found no way to toggle between screens when you press buttons down at the bottom. i know it does nothing but below is the simple layout i want to have, and switch between "myframe1" and "myframe2" kind of like the Apple App Store layout. is this possible?
from tkinter import *
tk = Tk()
tk.geometry("300x300")
myframe1 = Frame(tk,background="green",width=300,height=275)
myframe1.pack()
myframe2 = Frame(tk,background="cyan",width=300,height=275)
myframe2.pack()
btnframe = Frame(tk)
btn1 = Button(btnframe,text="screen1",width=9)
btn1.pack(side=LEFT)
btn2 = Button(btnframe,text="screen2",width=9)
btn2.pack(side=LEFT)
btn3 = Button(btnframe,text="screen3",width=9)
btn3.pack(side=LEFT)
btn4 = Button(btnframe,text="screen4",width=9)
btn4.pack(side=LEFT)
myframe1.pack()
btnframe.pack()
tk.mainloop()
something for you to get started with:
def toggle(fshow,fhide):
fhide.pack_forget()
fshow.pack()
btn1 = Button(btnframe,text="screen1", command=lambda:toggle(myframe1,myframe2),width=9)
btn1.pack(side=LEFT)
btn2 = Button(btnframe,text="screen2",command=lambda:toggle(myframe2,myframe1),width=9)
btn2.pack(side=LEFT)
Are you looking for something like a tabbed widget? You could use forget and pack as suggested here
Here is a class that I use in my code that works:
class MultiPanel():
"""We want to setup a pseudo tabbed widget with three treeviews. One showing the disk, one the pile and
the third the search results. All three treeviews should be hooked up to exactly the same event handlers
but only one of them should be visible at any time.
Based off http://code.activestate.com/recipes/188537/
"""
def __init__(self, parent):
#This is the frame that we display
self.fr = tki.Frame(parent, bg='black')
self.fr.pack(side='top', expand=True, fill='both')
self.widget_list = []
self.active_widget = None #Is an integer
def __call__(self):
"""This returns a reference to the frame, which can be used as a parent for the widgets you push in."""
return self.fr
def add_widget(self, wd):
if wd not in self.widget_list:
self.widget_list.append(wd)
if self.active_widget is None:
self.set_active_widget(0)
return len(self.widget_list) - 1 #Return the index of this widget
def set_active_widget(self, wdn):
if wdn >= len(self.widget_list) or wdn < 0:
logger.error('Widget index out of range')
return
if self.widget_list[wdn] == self.active_widget: return
if self.active_widget is not None: self.active_widget.forget()
self.widget_list[wdn].pack(fill='both', expand=True)
self.active_widget = self.widget_list[wdn]