Scroll not working for dropdown selection in PySimpleGUI

Question

When I use keyboard for dropdown selection, scroll doesn't move up and down,so I am not able to see which one is selected right now. How to move scroll up and down when keyboard is pressed up and down. My sample code is as following:

import PySimpleGUI as sg

class GUI():
    def __init__(self):
        self.data = [(10), (20), (30), (40), (50), (60), (70), (80), (90), (100)]
        self.work_order_currrent_selection_index = 0

    def run(self):
        layout = [[sg.Listbox(values=self.data, size=(35, 3), enable_events=True, key='selected_key')]]
        # Create the Window
        self.testWindow = sg.Window('Test', return_keyboard_events=True).Layout(layout).Finalize()
        self.testWindow.Maximize()
        self.testWindow.Element('selected_key').Update(set_to_index=0) 
        # Event Loop to process "events"
        while True:
            event, values = self.testWindow.Read()
            if event in('Up:111', '16777235'):
                if(hasattr(self, 'testWindow')):
                    self.work_order_currrent_selection_index = (self.work_order_currrent_selection_index - 1) % len(self.data)
                    self.testWindow.Element('selected_key').Update(set_to_index=self.work_order_currrent_selection_index) 
            elif event in ('Down:116',' 16777237'):
                if(hasattr(self, 'testWindow')):
                    self.work_order_currrent_selection_index = (self.work_order_currrent_selection_index + 1) % len(self.data)
                    self.testWindow.Element('selected_key').Update(set_to_index=self.work_order_currrent_selection_index)  

        self.testWindow.Close()

if __name__ == '__main__':
    app = GUI()
    app.run()

When application launch first time I just able to see three dropdown as,

I pressed down arrow key then selection go down one by one like that,

But after selection of 30, on the down key press selection move to next one like 40, 50.. except scrolling, so I am not able to see which one is selected now. Is there any way to move selection along with scrolling?

See the fourth image, here selection moved to 40 but scroll not moved down. Same issue with up key pressed.

Answer 1

Maybe this will get you a little closer to what you're looking for

import PySimpleGUI as sg

class GUI():
    def __init__(self):
        self.data = [(10), (20), (30), (40), (50), (60), (70), (80), (90), (100)]
        self.work_order_currrent_selection_index = 0

    def run(self):
        layout = [[sg.Listbox(values=self.data, size=(35, 3), enable_events=True, key='selected_key')]]
        # Create the Window
        self.testWindow = sg.Window('Test', layout, return_keyboard_events=True, finalize=True)
        # self.testWindow.Maximize()
        self.testWindow.Element('selected_key').Update(set_to_index=0)
        # Event Loop to process "events"
        while True:
            event, values = self.testWindow.Read()
            if event is None:
                break
            if event.startswith('Up'):
                self.work_order_currrent_selection_index = (self.work_order_currrent_selection_index - 1) % len(self.data)
                self.testWindow['selected_key'].Update(set_to_index=self.work_order_currrent_selection_index,scroll_to_index=self.work_order_currrent_selection_index )
            elif event.startswith('Down'):
                self.work_order_currrent_selection_index = (self.work_order_currrent_selection_index + 1) % len(self.data)
                self.testWindow['selected_key'].Update(set_to_index=self.work_order_currrent_selection_index, scroll_to_index=self.work_order_currrent_selection_index)

        self.testWindow.Close()

if __name__ == '__main__':
    app = GUI()
    app.run()