python - How to bind a keypress to a button in Tkinter

Question

My Senior Project involves a robot I can control over wifi. I am using a Raspberry Pi and a Tkinter window to send commands to the robot. I have the rough draft of my Tkinter window, but I am wondering if there is a way to bind the button press to the arrow keys. That way I can control the robot by using my arrow keys rather than clicking on each button. Here is my code, what would I have to add?

Code:

from Tkinter import *


message = ""

class App:

    def __init__(self, master):

        frame=Frame(master)
        frame.grid()

        status = Label(master, text=message)
        status.grid(row = 0, column = 0)

        self.leftButton = Button(frame, text="<", command=self.leftTurn)
        self.leftButton.grid(row = 1, column = 1)

        self.rightButton = Button(frame, text=">", command=self.rightTurn)
        self.rightButton.grid(row = 1, column = 3)

        self.upButton = Button(frame, text="^", command=self.upTurn)
        self.upButton.grid(row = 0, column = 2)

        self.downButton = Button(frame, text="V", command=self.downTurn)
        self.downButton.grid(row=2, column = 2)

    def leftTurn(self):
        message = "Left"
        print message

    def rightTurn(self):
        message = "Right"
    print message

    def upTurn(self):
        message = "Up"
        print message

    def downTurn(self):
        message = "Down"
        print message



root = Tk()
root.geometry("640x480")
root.title("Rover ")

app = App(root)

root.mainloop()

Answer 1

I believe what you want is to bind the key press to the frame/function. Tkinter has its own event and binding handling built in which you can read up on here.

Here is quick example which you should be able to adapt your program.

from tkinter import *

root = Tk()

def yourFunction(event):
    print('left')

frame = Frame(root, width=100, height=100)

frame.bind("<Left>",yourFunction)   #Binds the "left" key to the frame and exexutes yourFunction if "left" key was pressed
frame.pack()

root.mainloop()