Direct link to pre-selected items

[giswqs]

Thank you for creating this nice multi-apps template. I wondered if it is possible to generate a direct link to the pre-selected item. The instructions from https://discuss.streamlit.io/t/direct-link-to-pre-selected-items/4817 works for a single app, but I can't get it to work for multi-apps.

For example, I created this multi-apps based on your template.

• App: https://share.streamlit.io/giswqs/leafmap-apps/app.py
• GitHub: https://github.com/giswqs/leafmap-apps

When users select an item from the navigation panel, the URL will reflect the change (e.g., page=Demo). However, when users directly navigate to the URL by clicking the link below, it will always redirect to the home page rather than the pre-selected item. Any advice? Thanks.
https://share.streamlit.io/giswqs/leafmap-apps/app.py?page=Demo

Relevant source code: https://github.com/giswqs/leafmap-apps/blob/master/multiapp.py#L45

[upraneelnihar]

Hi,
We can try using the session state of the radio button to choose the required page from URL.

I have tried by modifying the run function in multiapp.py with following code, it solves the problem of navigating through URL. However I observed that this introduces a new issue where in we have to click twice on a radio button if you are selecting it from the interface.

I was unable to fix the later issue, but you can try along these lines and see if you can find a better solution for this.

    def run(self):
        app_state = st.experimental_get_query_params()
        app_state = {k: v[0] if isinstance(v, list) else v for k, v in app_state.items()} # fetch the first item in each query string as we don't have multiple values for each query string key in this example
        
        #st.write('before', app_state)
        
        titles = [a['title']  for a in self.apps]
        functions = [a['function'] for a in self.apps]
        default_radio = titles.index(app_state["page"]) if "page" in app_state else 0

        title = st.sidebar.radio(
            'Go To',
            titles,
            index=default_radio,
            key='radio')

        app_state['page'] = st.session_state.radio
        #st.write('after', app_state)

        st.experimental_set_query_params(**app_state)
        functions[titles.index(title)]()

[giswqs]

Thanks a lot for this. It seems working fine on my local computer. However, when deployed to streamlit.io, the direct link is being redirected to the home page.

https://share.streamlit.io/giswqs/leafmap-apps/app.py?page=Dual

Source code: https://github.com/giswqs/leafmap-apps/blob/master/multiapp.py

[giswqs]

Interestingly, this direct link works https://share.streamlit.io/giswqs/leafmap-apps/app.py?page=Demo
Other direct links don't work.

[upraneelnihar]

Thanks for testing the code.
I will try to find a better way to solve this problem. I will get back to you once I have a solution for this.