python - How can I identify when a Button is released in Tkinter? -


i'm using tkinter make gui , drive robot.

i have 4 buttons: forward, right, backward , left. want make robot move long button being pressed, , stop when button released.

how can identify when button released in tkinter?

you can create bindings <buttonpress> , <buttonrelease> events independently.

a starting point learning events , bindings here: http://effbot.org/tkinterbook/tkinter-events-and-bindings.htm

here's working example:

import tkinter tk import time  class example(tk.frame):     def __init__(self, *args, **kwargs):         tk.frame.__init__(self, *args, **kwargs)         self.button = tk.button(self, text="press me!")         self.text = tk.text(self, width=40, height=6)         self.vsb = tk.scrollbar(self, command=self.text.yview)         self.text.configure(yscrollcommand=self.vsb.set)          self.button.pack(side="top")         self.vsb.pack(side="right", fill="y")         self.text.pack(side="bottom", fill="x")          self.button.bind("<buttonpress>", self.on_press)         self.button.bind("<buttonrelease>", self.on_release)      def on_press(self, event):         self.log("button pressed")      def on_release(self, event):         self.log("button released")      def log(self, message):         = time.strftime("%i:%m:%s", time.localtime())         self.text.insert("end", + " " + message.strip() + "\n")         self.text.see("end")  if __name__ == "__main__":     root = tk.tk()     example(root).pack(side="top", fill="both", expand=true)     root.mainloop()

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