Plan for standard UI layouts and event listeners?

🎈 Using Streamlit
1

HI,
I have begun using streamlit and I like it, it’s simple and effective.

My first app was an image labeler (10 images, drop downs to select the labels and a save button) and I had to use a little hack to save when pressing the save button by calling the save function and triggering a RerunException to load new images. It works fine but it feels a little bit hacky.

Which leads me to the following question, does streamlit have the ambition to become a full fledged frontend library with event listeners and layouts? Something like Kivy for web apps.
Layouts example would be BoxLayout, FloatLayout, GridLayout
EventListeners examples would be on_click, on_hover, on_mouse_down, on_mouse_up, on_key_press etc

I would be absolutely delighted if it did as all pythonistas know too well that writing frontend code with web tech is not easy compared to a regular UI library (kivy, pyQT etc).

Please advise

1 Like
2

Another question is state management / stateful apps. This is what I am currently using:

import os
import pickle
import streamlit as st

class State:
    def __init__(self, path='state.pickle', default_state_class=dict):
        self.path = path
        self.default_state_class = default_state_class

    def load(self):
        if os.path.exists(self.path):
            with open(self.path, 'rb') as inf:
                self.state = pickle.load(inf)
        else:
            self.state = self.default_state_class()

    def get_state(self):
        return self.state

    def save(self):
        with open(self.path, 'wb') as outf:
            pickle.dump(self.state, outf)

def rerun():
    raise st.script_runner.RerunException(st.script_request_queue.RerunData(None))

def app():
    store = State()
    store.load()

    name = store.get_state().get('name', None)
    if name:
        st.text(f'Hello {name}')
    else:
        st.text(f'Please enter your name')
        name_input = st.text_input('your name')
        name = name_input

        if name != '':
            store.get_state()['name'] = name

        store.save()
        next_page = st.button('Next page')
        if next_page:
            rerun()

if __name__ == "__main__":
    app()