I'm not at all familiar with Tkinter's validatecommands, but I have done some research and would like to implement it in a widget that creates a tree graph from a bunch of entries. I want to restrict each entry so that the user can create lists of numbers from 0 to the highest row, not including the same row. So, for example, Row 0 entry can't have 0 in it or 12. So far I have only attempted to restrict the input from being the same value as the row, but I haven't been able to get that to work. I must be implementing the validate command incorrectly.
Any help would be much appreciated.
import tkinter as tk
class widget:
def __init__(self,master):
# vcmd = (master.register(self.validate),
# '%d', '%i', '%P', '%s', '%S', '%v', '%V', '%W')
self.master = master
self.entryNumbers = tk.Entry(master,justify = tk.CENTER)
self.entryNumbers.insert(0, "5")
self.entryNumbers.grid(row = 0,column = 0,columnspan =2,sticky="EW")
self.createEntriesButton = tk.Button(master,text = "Create Entries",command = self.createEntries)
self.createEntriesButton.grid(row = 1, column = 0,columnspan = 2,sticky="EW")
def createEntries(self):
self.entryNumbers.grid_forget()
self.createEntriesButton.grid_forget()
self.entries = []
self.entryLabels = []
vcmd = self.master.register(self.validateEntry)
for i in range(int(self.entryNumbers.get())):
self.entryLabels.append(tk.Label(self.master,text = "Row {}".format(i)))
self.entryLabels[-1].grid(row = i,column = 0)
self.entries.append(tk.Entry(self.master, validatecommand=(vcmd,'%P',i)))
self.entries[-1].grid(row = i,column = 1)
self.addEntriesButton = tk.Button(self.master,text = "Add Entries",command = self.addEntry)
self.addEntriesButton.grid(row = i+1, column = 0,columnspan = 2,sticky="EW")
def addEntry(self):
count = len(self.entries)
vcmd = self.master.register(self.validateEntry)
self.entryLabels.append(tk.Label(self.master,text = "Row {}".format(count)))
self.entryLabels[-1].grid(row = count+1,column = 0)
self.entries.append(tk.Entry(self.master, validatecommand=(vcmd,'%P',count)))
self.entries[-1].grid(row = count+1,column = 1)
self.addEntriesButton.grid(row = count+2, column = 0,columnspan = 2,sticky="EW")
def validateEntry(self,P,row):
if P != row:
return True
else:
return False
root1=tk.Tk()
widget(root1)
root1.mainloop()
Also, can vcmd be a member variable? I would like to only initialize it once?
I figured it out using a lambda function:
vcmd = lambda row:(self.master.register(self.validateEntry),'%P',row)
for i in range(int(self.entryNumbers.get())):
self.entryLabels.append(tk.Label(self.master,text = "Row {}".format(i)))
self.entryLabels[-1].grid(row = i,column = 0)
self.entries.append(tk.Entry(self.master, validate = "all", validatecommand=vcmd(i)))