huixiang_app/lib/utils/send_location_dialog.dart

import 'dart:async';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';

import 'package:geolocator/geolocator.dart';

class SendLocationDialog extends StatefulWidget {

  const SendLocationDialog({
    Key key,
  }) : super(key: key);

  @override
  SendLocationDialogState createState() => SendLocationDialogState();
}

class SendLocationDialogState extends State<SendLocationDialog> {
  bool disabled = false;
  bool denied = false;
  bool isSending = false;
  Position position;
  Object error;

  @override
  void initState() {
    super.initState();
    requestLocation();
  }

  Future<void> requestLocation() async {
    if (!(await Geolocator.isLocationServiceEnabled())) {
      setState(() => disabled = true);
      return;
    }
    var permission = await Geolocator.checkPermission();
    if (permission == LocationPermission.denied) {
      permission = await Geolocator.requestPermission();
      if (permission == LocationPermission.denied) {
        setState(() => denied = true);
        return;
      }
    }
    if (permission == LocationPermission.deniedForever) {
      setState(() => denied = true);
      return;
    }
    try {
      Position position;
      try {
        position = await Geolocator.getCurrentPosition(
          desiredAccuracy: LocationAccuracy.best,
          timeLimit: const Duration(seconds: 30),
        );
      } on TimeoutException {
        position = await Geolocator.getCurrentPosition(
          desiredAccuracy: LocationAccuracy.medium,
          timeLimit: const Duration(seconds: 30),
        );
      }
      setState(() => this.position = position);
    } catch (e) {
      setState(() => error = e);
    }
  }

  void sendAction() async {
    setState(() => isSending = true);
    final body =
        'https://www.openstreetmap.org/?mlat=${position.latitude}&mlon=${position.longitude}#map=16/${position.latitude}/${position.longitude}';
    final uri =
        'geo:${position.latitude},${position.longitude};u=${position.accuracy}';
    Navigator.of(context, rootNavigator: false).pop();
  }

  @override
  Widget build(BuildContext context) {
    Widget contentWidget;
    if (position != null) {
      // contentWidget = MapBubble(
      //   latitude: position.latitude,
      //   longitude: position.longitude,
      // );
      contentWidget = Text("MapBubble");
    } else if (disabled) {
      contentWidget = Text("locationDisabledNotice");
    } else if (denied) {
      contentWidget = Text("locationPermissionDeniedNotice");
    } else if (error != null) {
      contentWidget =
          Text(error.toString());
    } else {
      contentWidget = Row(
        mainAxisSize: MainAxisSize.min,
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          const CupertinoActivityIndicator(),
          const SizedBox(width: 12),
          Text("obtainingLocation"),
        ],
      );
    }
    return AlertDialog(
      title: Text("shareLocation"),
      content: contentWidget,
      actions: [
        TextButton(
          onPressed: Navigator.of(context, rootNavigator: false).pop,
          child: Text("cancel"),
        ),
        if (position != null)
          TextButton(
            onPressed: isSending ? null : sendAction,
            child: Text("send"),
          ),
      ],
    );
  }
}