Check if client is native

[ZeroPoint095]

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Example Code

from nicegui import ui, app
from webview import FileDialog

@ui.page('/')
async def page():
    """The UI entry point (after nicegui.ui.run() is called)."""

    async def open_dialog():

        is_native_client = True

        # suggested solution (perhaps by saving the native client ID and comparing it with `ui.context.client.id`)
        # is_native_client = ui.context.client.is_native()

        if is_native_client:
            # only the native client can reach this code
            selected_folder = await app.native.main_window.create_file_dialog(dialog_type=FileDialog.FOLDER)
            dir.set_value(selected_folder)
        else:
            # web browsers that navigated to "http://localhost:1234" reach this code
            ui.notify("Not possible in web browser!")

    ui.label("Selected folder:")
    dir = ui.input("None").classes('w-screen')
    ui.button("Browse...", on_click=lambda: open_dialog())

ui.run(port=1234, native=True)

Description

I would like to open a file dialog when using the native window. In my use case, the UI can also be opened remotely via a web browser.
In the above example, the file dialog works fine for the native client, but if the remote user does this, the dialog is opened in the native client.

Alternatively, I could use a tkinter file dialog as proposed in #283 (comment), but this would obviously only work if the file structure of the remote user is identical to that of the host/native, as the file dialog shows the file system of the remote user and not the host.

I am aware of the local file picker example , but this is not a use case I wish to handle in my implementation

NiceGUI Version

3.2.0

Python Version

3.12.7

Browser

Chrome, Other

Operating System

Windows

Additional Context

No response

[rodja]

You can set a custom user agent for native mode via start_args:

#!/usr/bin/env python3
from fastapi import Request
from nicegui import app, ui

def root(request: Request):
    user_agent = request.headers.get('user-agent', '').lower()

    if 'pywebview' in user_agent:
        ui.label('✓ Native app detected').classes('text-green text-2xl')
    else:
        ui.label('✗ Regular browser detected').classes('text-blue text-2xl')

app.native.start_args['user_agent'] = 'NiceGUI-Native/1.0 (pywebview)'
ui.run(root, native=True)

[ZeroPoint095]

This is perfect. Thanks so much!