android - 设置位置管理器 RequestLocationUpdate

Question

我是 Android 和 Xamarin 世界的新手。我正在尝试为位置管理器创建一个单独的类以用于不同的 Activity 。这是我的代码

using System;
using Android.Content;
using Android.Locations;


namespace MyLocation
{
 public class LocationManagerActivity 
 {
    private LocationManager _locationManager;
    private Geocoder _geocoder;
    string bestProvider;
    private Context locationContext;

    public LocationManagerActivity (Context lContext)
    {
        locationContext = lContext;
    }

    private void getCurrentLocation()
    {
        string provider = LocationManager.GpsProvider;

        if (_locationManager.IsProviderEnabled (provider)) {

            _locationManager.RequestLocationUpdates (1000, 100, null, locationContext);
        }
    }

    private void InitializeLocationManager()
    {
        _geocoder = new Geocoder (locationContext);

        _locationManager = (LocationManager)locationContext.GetSystemService(Context.LocationService);

        var criteria = new Criteria() { Accuracy = Accuracy.NoRequirement };
        bestProvider = _locationManager.GetBestProvider(criteria, true);

        Location lastKnownLocation = _locationManager.GetLastKnownLocation(bestProvider);

        if (lastKnownLocation != null)
        {
            string temp = string.Format("Last known location lat: {0}, long: {1}",
                lastKnownLocation.Latitude, lastKnownLocation.Longitude);

            //string tag = "Last known location: ";

            //Log.Info (tag, temp);
        }

        _locationManager.RequestLocationUpdates(bestProvider, 60000, 20, this);

    }
}
}

问题出在行上

locationManager.RequestLocationUpdates (1000, 100, null, locationContext);

参数 4 必须是 Android.App.PendingIntent。我该如何设置它，因为类(class)不是 Activity 。

Answer 1

有一个 RequestLocationUpdates 的重载，它接收一个 LocationListener。参见 The docs .

所以你可以让你的类在 Xamarin 中实现 ILocationListener 并实现所需的方法，例如 onLocationChanged 等。继承自 Java.Lang.Object) 你应该让你的类继承自 Java.Lang.Object 因为它会为你处理 Handle/Disposing。

public class LocationManagerActivity : Java.Lang.Object, ILocationListener

那么你可以这样做

_locationManager.RequestLocationUpdates(bestProvider, 60000, 20, this);