I have own raster tiles created from QGIS. They are okey, and work on windows app mode by starting python server at http://localhost:8000 and attribute looks like this url_template="http://localhost:8000/{z}/{x}/{y}.jpg",, but this solution doesn’t work at web mode and i am putting my script on github pages. It will be perfect to use local path like in leafmap "./{z}/{x}/{y}.jpg", but this also not working.

This is my Map config for flet map:

main_map = map.Map(
                    expand=True,
                    initial_center=map.MapLatitudeLongitude(50.965125,18.286120),
                    initial_zoom=12,
                    interaction_configuration=map.MapInteractionConfiguration(
                        flags=map.MapInteractiveFlag.ALL
                    ),
                    on_init=lambda e: print(f"Initialized Map"),
                    on_tap=handle_tap,
                    on_secondary_tap=handle_tap,
                    on_long_press=handle_tap,
                    on_event=lambda e: print(e),
                    layers=[
                        map.TileLayer(
                            url_template="https://tile.openstreetmap.org/{z}/{x}/{y}.png",
                            # url_template="./{z}/{x}/{y}.jpg", <-- I wanna something like this 
                            # url_template="http://localhost:8000/{z}/{x}/{y}.jpg",
                            on_image_error=lambda e: print("TileLayer Error"),
                        ),
                        map.RichAttribution(
                            attributions=[
                                map.TextSourceAttribution(
                                    text="OpenStreetMap Contributors",
                                    on_click=lambda e: e.page.launch_url(
                                        "https://openstreetmap.org/copyright"
                                    ),
                                ),
                                map.TextSourceAttribution(
                                    text="Flet",
                                    on_click=lambda e: e.page.launch_url("https://flet.dev"),
                                ),
                            ]
                        ),
                        map.SimpleAttribution(
                            text="Flet",
                            alignment=ft.alignment.top_right,
                            on_click=lambda e: print("Clicked SimpleAttribution"),
                        ),
                        map.MarkerLayer(
                            ref=marker_layer_ref,
                            markers=[
                                map.Marker(
                                    content=ft.Icon(ft.Icons.LOCATION_ON),
                                    coordinates=map.MapLatitudeLongitude(50.965125,18.286120),
                                ),
                                map.Marker(
                                    content=ft.Icon(ft.Icons.LOCATION_ON),
                                    coordinates=map.MapLatitudeLongitude(10, 10),
                                ),
                                map.Marker(
                                    content=ft.Icon(ft.Icons.LOCATION_ON),
                                    coordinates=map.MapLatitudeLongitude(25, 45),
                                ),
                            ],
                        ),
                        map.CircleLayer(
                            ref=circle_layer_ref,
                            circles=[
                                map.CircleMarker(
                                    radius=10,
                                    coordinates=map.MapLatitudeLongitude(50.965125,18.306120),
                                    color=ft.Colors.RED,
                                    border_color=ft.Colors.BLUE,
                                    border_stroke_width=4,
                                ),
                            ],
                        ),
                        map.PolygonLayer(
                            polygons=[
                                map.PolygonMarker(
                                    label="Popular Touristic Area",
                                    label_text_style=ft.TextStyle(
                                        color=ft.Colors.BLACK,
                                        size=15,
                                        weight=ft.FontWeight.BOLD,
                                    ),
                                    color=ft.Colors.with_opacity(0.3, ft.Colors.BLUE),
                                    coordinates=[
                                        map.MapLatitudeLongitude(10, 10),
                                        map.MapLatitudeLongitude(30, 15),
                                        map.MapLatitudeLongitude(25, 45),
                                    ],
                                ),
                            ],
                        ),
                        map.PolylineLayer(
                            polylines=[
                                map.PolylineMarker(
                                    border_stroke_width=3,
                                    border_color=ft.Colors.RED,
                                    gradient_colors=[ft.Colors.BLACK, ft.Colors.BLACK],
                                    color=ft.Colors.with_opacity(0.6, ft.Colors.GREEN),
                                    coordinates=[
                                        map.MapLatitudeLongitude(10, 10),
                                        map.MapLatitudeLongitude(30, 15),
                                        map.MapLatitudeLongitude(25, 45),
                                    ],
                                ),
                            ],
                        ),
                    ],
                )

Full srcipt and example tiles (assets folder) is in this github project and there are deploy page

That’s how it look with OSM TiledLayer

That’s i wanna to look on web, this is from exe mode for flet app