android - 当应用程序在 Android 上后台运行时如何更新地图 UI 上的位置

Question

当应用程序在 Android 的后台运行时，我想更新地图 UI 上的位置。我知道这可以使用服务类。我试过使用服务类，但我无法实时看到我的用户界面。

private void startLocationUpdates() {
    mSettingsClient
            .checkLocationSettings(mLocationSettingsRequest)
            .addOnSuccessListener(this, new OnSuccessListener<LocationSettingsResponse>() {
                @SuppressLint("MissingPermission")
                @Override
                public void onSuccess(LocationSettingsResponse locationSettingsResponse) {
                    Log.i(TAG, "All location settings are satisfied.");

                    Toast.makeText(getApplicationContext(), "Started location updates!", Toast.LENGTH_SHORT).show();

                    //noinspection MissingPermission
                    mFusedLocationClient.requestLocationUpdates(mLocationRequest,
                            mLocationCallback, Looper.myLooper());

                    // Instantiating the class PolylineOptions to plot polyline in the map
                    PolylineOptions polylineOptions = new PolylineOptions();

                    // Setting the color of the polyline
                    polylineOptions.color(Color.RED);
                    polylineOptions.clickable(true);

                    // Setting the width of the polyline
                    polylineOptions.width(3);

                    // Setting points of polyline
                    polylineOptions.addAll(points);

                    // Adding the polyline to the map
                    mMap.addPolyline(polylineOptions);

                    updateLocationUI();
                }
            })
            .addOnFailureListener(this, new OnFailureListener() {
                @Override
                public void onFailure(@NonNull Exception e) {
                    int statusCode = ((ApiException) e).getStatusCode();
                    switch (statusCode) {
                        case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                            Log.i(TAG, "Location settings are not satisfied. Attempting to upgrade " +
                                    "location settings ");
                            try {
                                // Show the dialog by calling startResolutionForResult(), and check the
                                // result in onActivityResult().
                                ResolvableApiException rae = (ResolvableApiException) e;
                                rae.startResolutionForResult(MapsActivity.this, REQUEST_CHECK_SETTINGS);
                            } catch (IntentSender.SendIntentException sie) {
                                Log.i(TAG, "PendingIntent unable to execute request.");
                            }
                            break;
                        case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                            String errorMessage = "Location settings are inadequate, and cannot be " +
                                    "fixed here. Fix in Settings.";
                            Log.e(TAG, errorMessage);

                            Toast.makeText(MapsActivity.this, errorMessage, Toast.LENGTH_LONG).show();
                    }

                    updateLocationUI();
                }
            });
}

标签： android