chooseActiveRoute static method
Switches visual active route among those drawn by computeRoutesAndDraw.
Implementation
static Future<void> chooseActiveRoute(int index) async {
final c = _controller;
final res = _lastRoutes;
if (c == null || res == null) return;
for (final r in res.routes) {
final id = 'gmns_alt_${r.index}';
// Re-add polyline with new style (simple way to recolor)
await c.addPolyline(PolylineOptions(
id: id,
points: r.points,
color: r.index == index ? const Color(0xFF1976D2) : const Color(0x661976D2),
width: r.index == index ? 8 : 6,
));
}
_activeRouteIndex = index;
}