Maps and continuous location

The desktop Previewer has no phone GPS. Give it an explicit fictional route so the interface can be tested. Android ignores that simulation and uses device location after permission is granted.

from apkpy_lib import Screen, declare_permissions, location, map_view, run

declare_permissions([
    "android.permission.ACCESS_FINE_LOCATION",
    "android.permission.ACCESS_COARSE_LOCATION",
    "android.permission.ACCESS_BACKGROUND_LOCATION",
])
tracking = Screen(id="tracking")

preview_route = [
    {"lat": 40.7484, "lng": -73.9857},
    {"lat": 40.7492, "lng": -73.9838},
    {"lat": 40.7501, "lng": -73.9821},
]

map_panel = map_view(
    markers=[],
    route=preview_route,
    show_user=True,
    follow_user=True,
    screen=tracking,
)

def position_changed(success, lat, lng, accuracy, speed):
    if success:
        map_panel.set_location(lat, lng, accuracy)

location.watch(
    "courier",
    on_update=position_changed,
    interval=1500,
    min_distance=3,
    preview_route=preview_route,
    screen=tracking,
)

run(tracking)

For a road-aware path, call routes.calculate(...) only after the user asks for a route, decode it with route_points(...), then pass the result to map_panel.set_route(...).

Privacy and lifecycle

• do not infer a developer location in the Previewer;
• explain why foreground or background location is needed;
• stop watchers when tracking ends;
• expect indoor accuracy to be lower;
• test process recreation and Android background restrictions;
• treat route services as external network processors in your privacy policy.