Conditional disabling of widget

Question

In the following code, I have been trying to disable the entry1 widget every time I select 1 in the combobox and disable entry2 when i select 2 in combobox.

this is my code:

from Tkinter import *
import ttk

def refresh():
    if v.get() == 'A':
        entry1.state(['disabled'])
        entry2.state(['!disabled'])
    elif v.get() == 'B':
        entry2.state(['disabled'])
        entry1.state(['!disabled'])




root = Tk()
v = StringVar()
var = StringVar()

entry1 = ttk.Entry (root, textvariable= var)
entry1.grid(row=2, column=2, sticky=(E,W))

entry2 = ttk.Entry (root, textvariable= var)
entry2.grid(row=4, column=2, sticky=(E,W))


v_list=['A','B']
v.set(v_list[1])
v_optionmenu = apply(OptionMenu, (root,v) + tuple(v_list))
v_optionmenu.grid(column=4,row=11,sticky=(W,E))

var = v
root.bind('<Return>', lambda e: refresh)

root.mainloop()

I wanted to create condition based enabling and disabling of widgets. My conditions usually are:

selection in combobox Selection of radiobutton

Please Advice how i can go about it.

Answer 1

def refresh(*args):

    if  v.get() == 'Disable' :
        fb_entry.state(['disabled'])
        fw_entry.state(['disabled'])
        fb.set('')
        fw.set('')
    elif v.get() == 'Enable' :
        fb_entry.state(['!disabled'])
        fw_entry.state(['!disabled'])


root = Tk()
v = StringVar()
var = StringVar()

entry1 = ttk.Entry (root, textvariable= var)
entry1.grid(row=2, column=2, sticky=(E,W))

entry2 = ttk.Entry (root, textvariable= var)
entry2.grid(row=4, column=2, sticky=(E,W))


v_list=['Disable','Enable']
v.set(v_list[1])
v_optionmenu = apply(OptionMenu, (root,v) + tuple(v_list))
v_optionmenu.grid(column=4,row=11,sticky=(W,E))

var = v

root.bind('<Enter>',refresh_widget)
root.mainloop()

Answer 2

The piece you seem to be missing is that you can change the state with the configure method. Also, you can set a trace on a variable to have a function called when the value changes. Since you said you want to change the state based on a combobox, that is the technique you would use. You can do a similar trick with a radiobutton, though radiobuttons also have a command option which can be used instead of a trace.

Here's an example showing how to trigger a "refresh" function when a combobox changes:

import Tkinter as tk
import ttk

class SampleApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        tk.Tk.__init__(self, *args, **kwargs)

        self.choiceVar = tk.StringVar()

        self.e1 = ttk.Entry(self)
        self.e2 = ttk.Entry(self)
        self.cb = ttk.Combobox(self, textvariable=self.choiceVar,
                               values=["Enable 1 only", "Enable 2 only"])
        self.cb.set(self.cb.cget("values")[0])

        self.cb.pack(side="top")
        self.e1.pack(side="top")
        self.e2.pack(side="top")

        self.choiceVar.trace("w", self.on_trace_choice)
        self.refresh()

    def on_trace_choice(self, name, index, mode):
        self.refresh()

    def refresh(self):
        choice = self.cb.get()
        if choice == "Enable 1 only":
            self.e1.configure(state="normal")
            self.e2.configure(state="disabled")
        else:
            self.e1.configure(state="disabled")
            self.e2.configure(state="normal")

if __name__ == "__main__":
    app = SampleApp()
    app.mainloop()