import PySimpleGUI as sg # Testing async form, see if can have a slider # that adjusts the size of text displayed fontSize = 12 layout = [ [sg.Spin([sz for sz in range(6, 172)], font=('Helvetica 20'), initial_value=fontSize, change_submits=True, key='spin'), sg.Slider(range=(6, 172), orientation='h', size=(10, 20), change_submits=True, key='slider', font=('Helvetica 20')), sg.Text("Aa", size=(2, 1), font="Helvetica " + str(fontSize), key='text')] ] sz = fontSize window = sg.Window("Font size selector", layout, grab_anywhere=False) while True: event, values = window.read() if event is None or event == 'Quit': break sz_spin = int(values['spin']) sz_slider = int(values['slider']) sz = sz_spin if sz_spin != fontSize else sz_slider if sz != fontSize: fontSize = sz font = "Helvetica " + str(fontSize) window['text'].update(font=font) window['slider'].update(sz) window['spin'].update(sz) window.close()