如何将LatLng发送至ProximityIntentReceiver？修改代码支持经纬度输入

Got it, let's break down your two Android proximity alert needs step by step:

1. Sending LatLng Data to ProximityIntentReceiver #

To pass a LatLng to your ProximityIntentReceiver, bundle the latitude and longitude as extras in the broadcast Intent you use to create the PendingIntent. Here's how to do it:

Step 1: Attach LatLng to the Intent #

When setting up your proximity alert intent, add the LatLng coordinates as extra values:

// Create the base intent for your receiver
Intent intent = new Intent("com.example.a57050358.testboat.util.proximityintentreceiver");

// Add LatLng data as extras
intent.putExtra("TARGET_LAT", latLng.latitude);
intent.putExtra("TARGET_LNG", latLng.longitude);

// Use FLAG_UPDATE_CURRENT to ensure updated extras are passed to existing PendingIntents
PendingIntent proximityIntent = PendingIntent.getBroadcast(getContext(), 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

Step 2: Retrieve LatLng in the Receiver #

In your ProximityIntentReceiver class, extract the extras from the incoming intent to get the LatLng:

public class ProximityIntentReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        // Pull the coordinates from extras
        double lat = intent.getDoubleExtra("TARGET_LAT", 0.0);
        double lng = intent.getDoubleExtra("TARGET_LNG", 0.0);
        LatLng receivedLatLng = new LatLng(lat, lng);

        // Use the received LatLng (e.g., show a notification or trigger an action)
        Toast.makeText(context, "Entered zone near: " + receivedLatLng, Toast.LENGTH_SHORT).show();
    }
}

2. Modify GeocoderTask to Accept Direct LatLng Input #

Your original task uses a location name to fetch coordinates—let's rework it to take a LatLng directly, skip name-based geocoding, and set up the proximity alert using the provided coordinates. Here's the revised code:

private class GeocoderTask extends AsyncTask<LatLng, Void, Address> {
    @Override
    protected Address doInBackground(LatLng... latLngs) {
        // Get the input LatLng from parameters
        LatLng targetLatLng = latLngs[0];
        Geocoder geocoder = new Geocoder(getContext());
        Address address = null;

        try {
            // Fetch address details from the provided coordinates (limit to 1 result)
            List<Address> addresses = geocoder.getFromLocation(
                    targetLatLng.latitude,
                    targetLatLng.longitude,
                    1
            );
            if (addresses != null && !addresses.isEmpty()) {
                address = addresses.get(0);
            }
        } catch (IOException e) {
            e.printStackTrace();
            // Optional: Handle geocoding failures (e.g., no network access)
        }
        return address;
    }

    @SuppressLint("MissingPermission")
    @Override
    protected void onPostExecute(Address address) {
        LatLng targetLatLng = null;

        // Get the target coordinates (either from the address or original input)
        if (address != null) {
            targetLatLng = new LatLng(address.getLatitude(), address.getLongitude());
        } else {
            Toast.makeText(getContext(), "Failed to fetch address details", Toast.LENGTH_SHORT).show();
            return;
        }

        // Set up marker and circle for the map
        String addressText = address != null 
                ? String.format("%s, %s",
                        address.getMaxAddressLineIndex() > 0 ? address.getAddressLine(0) : "",
                        address.getCountryName())
                : "Custom Location";

        MarkerOptions markerOptions = new MarkerOptions()
                .position(targetLatLng)
                .title(addressText);

        CircleOptions circleOptions = new CircleOptions()
                .center(targetLatLng)
                .radius(Rd);

        // Create proximity intent with LatLng extras (as we did in part 1)
        Intent intent = new Intent("com.example.a57050358.testboat.util.proximityintentreceiver");
        intent.putExtra("TARGET_LAT", targetLatLng.latitude);
        intent.putExtra("TARGET_LNG", targetLatLng.longitude);

        PendingIntent proximityIntent = PendingIntent.getBroadcast(
                getContext(),
                0,
                intent,
                PendingIntent.FLAG_UPDATE_CURRENT
        );

        // Add the proximity alert using direct coordinates
        locationManager.addProximityAlert(
                targetLatLng.latitude,
                targetLatLng.longitude,
                Rd,
                -1,
                proximityIntent
        );

        // Register the receiver (note: consider registering this in onCreate() to avoid duplicate receivers)
        IntentFilter filter = new IntentFilter("com.example.a57050358.testboat.util.proximityintentreceiver");
        getContext().registerReceiver(new ProximityIntentReceiver(), filter);

        Toast.makeText(getContext(), "Proximity alert set successfully", Toast.LENGTH_SHORT).show();
    }
}

Key Updates: #

• Changed the AsyncTask generic type to <LatLng, Void, Address> to accept a LatLng input and return a single address.
• Replaced getFromLocationName() with getFromLocation() to fetch address details directly from coordinates.
• Added logic to pass the target LatLng to the ProximityIntentReceiver via intent extras.
• Simplified the address handling since we're only fetching one result for the given coordinates.

How to Use the Revised Task: #

Call it with a LatLng instead of a location name:

// Example: Set alert for the Eiffel Tower
LatLng eiffelTower = new LatLng(48.8584, 2.2945);
new GeocoderTask().execute(eiffelTower);

内容的提问来源于stack exchange，提问作者PPZ