[Question] bind_return_key does not work with Combo

[starrry123]

Type of Issue (Enhancement, Error, Bug, Question)

Question

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Operating System

Windows

PySimpleGUI Port (tkinter)

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Versions

Version information can be obtained by calling sg.main_get_debug_data()
Or you can print each version shown in ()

Python version (3.7.4)

PySimpleGUI Version (4.40.0)

GUI Version (tkinter)

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Your Experience In Months or Years (optional)

Years Python programming experience

Years Programming experience overall

Have used another Python GUI Framework? (tkinter, Qt, etc) (yes)

Anything else you think would be helpful?

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Troubleshooting

These items may solve your problem. Please check those you've done by changing - [ ] to - [X]

• Searched main docs for your problem www.PySimpleGUI.org
• Looked for Demo Programs that are similar to your goal Demos.PySimpleGUI.org
• If not tkinter - looked for Demo Programs for specific port
• For non tkinter - Looked at readme for your specific port if not PySimpleGUI (Qt, WX, Remi)
• Run your program outside of your debugger (from a command line)
• Searched through Issues (open and closed) to see if already reported Issues.PySimpleGUI.org
• Tried using the PySimpleGUI.py file on GitHub. Your problem may have already been fixed but not released

Detailed Description

bind_return_key works with sg.Input, however it does not seems to work with Combo.

Code To Duplicate

A short program that isolates and demonstrates the problem (Do not paste your massive program, but instead 10-20 lines that clearly show the problem)

This pre-formatted code block is all set for you to paste in your bit of code:

# Paste your code here
import PySimpleGUI as sg


layout = [ [sg.Txt('Calculate 1/x:')],
           [sg.Combo(size=(8,1), key='-DENOMINATAOR-',values='1') ],
           [sg.Txt(size=(8,1), key='-OUTPUT-')  ],
           [sg.Button('Calculate', bind_return_key=True)]]

window = sg.Window('Math', layout)

while True:
    event, values = window.read()

    if event != sg.WIN_CLOSED:
        try:
            denominator = float(values['-DENOMINATAOR-'])
            calc = 1/denominator
        except:
            calc = 'Invalid'

        window['-OUTPUT-'].update(calc)
    else:
        break

Screenshot, Sketch, or Drawing

[jason990420]

First, workaround for sg.Combo here

window = sg.Window('Math', layout, finalize=True)
window['-DENOMINATAOR-'].bind('<Return>', 'Return') # Event `-DENOMINATAOR-Return`

It may take time to find how bind_return_key work, so will reply this latter.

[jason990420]

For sg.Input, it bind enter event to callback to find first sg.Button with option bind_return_key=True to as if the button was clicked. For sg.Combo, no code for this event binded, so it do nothing.

To be with same function, binding code required.

import PySimpleGUI as sg


layout = [ [sg.Txt('Calculate 1/x:')],
           [sg.Combo(size=(8,1), key='-DENOMINATAOR-',values='1') ],
           [sg.Txt(size=(20,1), key='-OUTPUT-')  ],     # revised width to fit floating number
           [sg.Button('Calculate', bind_return_key=True)]]

window = sg.Window('Math', layout, finalize=True)       # finalize=True required
combo = window['-DENOMINATAOR-']                        # new line #2
combo.Widget.bind('<Return>', combo._ReturnKeyHandler)  # new line #1

while True:

    event, values = window.read()
    print(event, values)
    if event != sg.WIN_CLOSED:
        try:
            denominator = float(values['-DENOMINATAOR-'])
            calc = 1/denominator
        except:
            calc = 'Invalid'

        window['-OUTPUT-'].update(calc)
    else:
        break

window.close()

[PySimpleGUI]

The Window.bind call can also be used if the desire is for the return key to always act like a button press. This will allow using the button's text and is easy to read.

These 2 calls map keyboard keys to Button keys for example.

window.bind('<F10>', 'Go')
window.bind('<Escape>', 'Exit')

The Demo Browser is how I found these examples (searched for window.bind)

[PySimpleGUI]

Added to version 4.41.2.1 on GitHub.

I've made it function like the Listbox's bind_return_key parameter. If the return key is pressed while on the element, it's the Combo's key that will be returned as the event.

import PySimpleGUI as sg

def main():
    layout = [  [sg.Text('My Window')],
                [sg.Input(key='-IN-')],
                [sg.Input(key='-IN2-')],
                [sg.Combo((1,2,3,4), size=(10,5), bind_return_key=True, k='-COMBO-')],
                [sg.Listbox((1,2,3,4), size=(10,5), bind_return_key=True, k='-LB-')],
                [sg.Text(size=(40,1), key='-EVENT-')],
                [sg.Text(size=(40,1), key='-VALUES-')],
                [sg.Button('Go'), sg.Button('Exit')]  ]

    window = sg.Window('Window Title', layout)

    while True:             # Event Loop
        event, values = window.read()
        print(event, values)
        if event == sg.WIN_CLOSED or event == 'Exit':
            break
        window['-EVENT-'].update(event)
        window['-VALUES-'].update(values)
    window.close()

if __name__ == '__main__':
    main()