Tkinter not refreshing on MacOs when writing to a Text

Question

I have a small Tkinter app to show some serial communication. It has two Text components (user_input and log) and a 'Send' button.

When 'Send' is pressed, whatever written in user_input is sent to the serial.

def send_clicked(self):
    data = self.user_input.get(1.0, END)[:-1] + '\0'
    self.serial.write(str(data))
    self.user_input.delete(1.0, END)

Also this method runs every 100 millis to display serial output in log Text component:

def read_serial(self):
    self.log.update()  # display input text
    self._read_character()
    self.after(100, self.read_serial)  # check serial again soon

def _read_character(self):
    c = self.serial.read()  # attempt to read a character from Serial
    # was anything read?
    while len(c) > 0:
        # get the buffer from outside of this function
        # check if character is a delimeter
        if c == '\r':
            c = ''  # don't want returns. chuck it
        if c == '\n':
            self.serial_buffer += "\n"  # add the newline to the buffer
            self.log.insert(END, self.serial_buffer)
            self.log.yview(END)
            self.serial_buffer = ""  # empty the buffer
        else:
            self.serial_buffer += c  # add to the buffer
        c = self.serial.read()

This works fine in windows, linux and mac.

Now I want to print ">> value" on the responses Text when the user clicks 'Send', so I redefine send_clicked:

def send_clicked(self):
    data = self.user_input.get(1.0, END)[:-1] + '\0'
    self.serial.write(str(data))
    self.log.insert(END, '>> %s\n' % data)
    self.log.yview(END)
    self.user_input.delete(1.0, END)

This causes the window to stop refreshing in MacOS (it works fine in linux and windows), I have to click outside the window and click back for it to refresh. Now I've aded a menu, I can also click a button in the menu to get an update.

Answer 1

If you're running OSX 10.9 (Mavericks), it is likely that this is the issue. I suggest updating your current version of Tcl/Tk or even updating to the latest version of Python (especially if you are still using 3.3). Hope this helps!