如何每60秒刷新python tkinter窗口的内容

Question

I have a python program that accesses databases for stuff that needs to be displayed on a screen. It's purpose is to display when a person's order is ready to be picked up. I have all the code to get the data and display it on the window. However, I need every 60 seconds to re-query the databases as some orders will be picked up and need to disappear from the list and some need to be added. I just don't know how to do this, as it appears that once the app.mainloop() is called, it takes human interaction with the window to make something happen. Any assistance would be greatly appreciated... Sorry for being long winded!

Answer 1

Here is an example I threw together to show you some basics of how you can use after() to check ever so many seconds to update your tracker.

Let me know if you have any questions.

import tkinter as tk


class Example(tk.Tk):
    def __init__(self):
        tk.Tk.__init__(self)
        self.geometry("600x400")
        self.current_ticket_number = 1
        self.data = [[97, "Mike"], [98, "Kaite"], [99, "Tom"]]

        self.display_frame = tk.Frame(self)
        self.display_frame.grid(row=2, column=0, columnspan=3, sticky="nsew")

        self.lbl1 = tk.Label(self, text="Next ticket number: {}".format(self.current_ticket_number))
        self.lbl1.grid(row=0, column=0)
        self.lbl2 = tk.Label(self, text="Customer Name: ".format(self.current_ticket_number))
        self.lbl2.grid(row=0, column=1)
        self.entry1 = tk.Entry(self)
        self.entry1.grid(row=0, column=2)

        tk.Button(self, text="Refresh List", command=self.refresh).grid(row=1, column=0, pady=5)
        tk.Button(self, text="Submit new ticket", command=self.new_ticket).grid(row=1, column=1, pady=5)

        self.timed_refresh()

    def new_ticket(self):
        x = self.entry1.get().strip()
        if x != "":
            self.data.append([self.current_ticket_number, x])
            #self.refresh() # you could do self.refresh() here if you want to update as soon as you create a ticket
            #I left it out though so you can see how after() works below.
            if self.current_ticket_number >= 99:
                self.current_ticket_number = 1
            else:
                self.current_ticket_number += 1

    def refresh(self):
        self.display_frame.destroy()
        self.display_frame = tk.Frame(self)
        self.display_frame.grid(row=2, column=0, columnspan=3, sticky="nsew")
        for ndex, item in enumerate(self.data):
            tk.Label(self.display_frame, text=r"Order #{} is ready for {}.".format(item[0], item[1])).grid(row=ndex, column=1)
            tk.Button(self.display_frame, text=r"Remove Ticket".format(item[0], item[1]), command=lambda x=ndex: self.remove_ticket(x)).grid(row=ndex, column=0)

    def remove_ticket(self, ndex):
        self.data.pop(ndex)
        self.refresh()

    def timed_refresh(self):
        #this after statement is set for every 6 seconds
        self.after(6000, self.timed_refresh)
        self.refresh()

if __name__ == "__main__":
    Example().mainloop()

Answer 2

Here is what I ended up with. Seems to do what I need it to do. Thanks for all the help, it was spot on.

class Application(tk.Frame):
    def __init__(self,master=None):
    self.createWidgets()

    def createWidgets(self):
        tk.Frame.__init__(self)
        self.pack()
        for b in range(0,int(len(myItems)/2)):
            #print (myItems[b])
            self.btn = tk.Button(self)
            self.btn["text"] = myItems[b,0]
            # self.btn["command"] = (lambda tck=b, binst=btn : pickUp(tck, binst))
            # self.btn["command"] =  lambda ticketNo=myItems[b,1] : self.pickUp(ticketNo)
            self.btn.pack(fill='x')

    def pp(self) :
        #print('Im in pp')
        self.destroy()
        getArrowDataAndUpdateSQLite()
        myItems = getDisplayData()
        app.createWidgets()
        app.master.after(30000, self.pp)

app = Application()
app.master.title('Customer Order Status')
app.master.after(30000,app.pp)
app.mainloop()