android - 处理多个地理围栏过渡与公共(public)区域

如果我有这两个地理围栏，在注册这些地理围栏之后，当我进入或离开这些圆的圆周时，我应该得到通知。但是，我不希望我的应用程序在我通过公共区域（即从一个圆圈到另一个圆圈）时发送通知。
有可能吗？如果是，那怎么办？

最佳答案

您必须使用class来监控您的围栏：

public class GeofenceReceiver extends BroadcastReceiver {
    Context context;

    Intent broadcastIntent = new Intent();

    @Override
    public void onReceive(Context context, Intent intent) {
        this.context = context;

        broadcastIntent.addCategory(GeofenceUtils.CATEGORY_LOCATION_SERVICES);

        if (LocationClient.hasError(intent)) {
            handleError(intent);
        } else {
            handleEnterExit(intent);
        }
    }

    private void handleError(Intent intent){
        // Get the error code
        int errorCode = LocationClient.getErrorCode(intent);

        // Get the error message
        String errorMessage = LocationServiceErrorMessages.getErrorString(
                context, errorCode);

        // Log the error
        Log.e(GeofenceUtils.APPTAG,
                context.getString(R.string.geofence_transition_error_detail,
                        errorMessage));

        // Set the action and error message for the broadcast intent
        broadcastIntent
                .setAction(GeofenceUtils.ACTION_GEOFENCE_ERROR)
                .putExtra(GeofenceUtils.EXTRA_GEOFENCE_STATUS, errorMessage);

        // Broadcast the error *locally* to other components in this app
        LocalBroadcastManager.getInstance(context).sendBroadcast(
                broadcastIntent);
    }


    private void handleEnterExit(Intent intent) {
        // Get the type of transition (entry or exit)
        int transition = LocationClient.getGeofenceTransition(intent);

        // Test that a valid transition was reported
        if ((transition == Geofence.GEOFENCE_TRANSITION_ENTER)
                || (transition == Geofence.GEOFENCE_TRANSITION_EXIT)) {

            // Post a notification
            List<Geofence> geofences = LocationClient
                    .getTriggeringGeofences(intent);
            String[] geofenceIds = new String[geofences.size()];
            String ids = TextUtils.join(GeofenceUtils.GEOFENCE_ID_DELIMITER,
                    geofenceIds);
            String transitionType = GeofenceUtils
                    .getTransitionString(transition);

            for (int index = 0; index < geofences.size(); index++) {
                Geofence geofence = geofences.get(index);
                ...do something with the geofence entry or exit. I'm saving them to a local sqlite db

            }
            // Create an Intent to broadcast to the app
            broadcastIntent
                    .setAction(GeofenceUtils.ACTION_GEOFENCE_TRANSITION)
                    .addCategory(GeofenceUtils.CATEGORY_LOCATION_SERVICES)
                    .putExtra(GeofenceUtils.EXTRA_GEOFENCE_ID, geofenceIds)
                    .putExtra(GeofenceUtils.EXTRA_GEOFENCE_TRANSITION_TYPE,
                            transitionType);

            LocalBroadcastManager.getInstance(MyApplication.getContext())
                    .sendBroadcast(broadcastIntent);

            // Log the transition type and a message
            Log.d(GeofenceUtils.APPTAG, transitionType + ": " + ids);
            Log.d(GeofenceUtils.APPTAG,
                    context.getString(R.string.geofence_transition_notification_text));

            // In debug mode, log the result
            Log.d(GeofenceUtils.APPTAG, "transition");

            // An invalid transition was reported
        } else {
            // Always log as an error
            Log.e(GeofenceUtils.APPTAG,
                    context.getString(R.string.geofence_transition_invalid_type,
                            transition));
        }
    }

    //Posts a notification in the notification bar when a transition
    private void sendNotification(String transitionType, String locationName) {

        // Create an explicit content Intent that starts the main Activity
        Intent notificationIntent = new Intent(context, MainActivity.class);

        // Construct a task stack
        TaskStackBuilder stackBuilder = TaskStackBuilder.create(context);

        // Adds the main Activity to the task stack as the parent
        stackBuilder.addParentStack(MainActivity.class);

        // Push the content Intent onto the stack
        stackBuilder.addNextIntent(notificationIntent);

        // Get a PendingIntent containing the entire back stack
        PendingIntent notificationPendingIntent = stackBuilder
                .getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);

        // Get a notification builder that's compatible with platform versions
        // >= 4
        NotificationCompat.Builder builder = new NotificationCompat.Builder(
                context);

        // Set the notification contents
        builder.setSmallIcon(R.drawable.ic_notification)
                .setContentTitle(transitionType + ": " + locationName)
                .setContentText(
                        context.getString(R.string.geofence_transition_notification_text))
                .setContentIntent(notificationPendingIntent);

        // Get an instance of the Notification manager
        NotificationManager mNotificationManager = (NotificationManager) context
                .getSystemService(Context.NOTIFICATION_SERVICE);

        // Issue the notification
        mNotificationManager.notify(0, builder.build());
    }

您应该为希望监视的每个区域创建监听器，比如说监听器1和监听器2。为了优化和集成这两个领域，最好的方法是使用MongoDB创建一个网格，在这种情况下，甚至可以在构建网格时集成两个以上的点。
假设您要以一些lat lon点的形式得到一个多边形，那么您可以生成一个grid如下：

# Method to get the min and max values for the polygon
def get_bounding_box(coords)
# get max and min coords
max = coords.inject({lat:0, lon:0}) do |max, c|
max[:lon] = c[0] if c[0] > max[:lon]
max[:lat] = c[1] if c[1] > max[:lat]
max
end
min = coords.inject({lat:MAX_LAT, lon:MAX_LON}) do |min, c|
min[:lon] = c[0] if c[0] < min[:lon]
min[:lat] = c[1] if c[1] < min[:lat]
min
end
# add a little padding to the max and min
max.each {|k, v| max[k] += 1 }
min.each {|k, v| min[k] -= 1 }

{min: min, max: max}
end

def generate_grid(bounds)
lon_range = bounds[:min][:lon]...bounds[:max][:lon]
lat_range = bounds[:min][:lat]...bounds[:max][:lat]

grid = []
lon_range.each do |lon|
lat_range.each do |lat|
grid << [lon + 0.25, lat + 0.25]
grid << [lon + 0.25, lat + 0.75]
grid << [lon + 0.75, lat + 0.25]
grid << [lon + 0.75, lat + 0.75]
end
end

grid
end

这种方法允许您使用智能电网实现very efficient地理围栏，以监控目标区域：
最近，MongoDB还增加了对Android的支持，从而为您的Android应用程序后端集成提供了一种简单的方法。事实上，使用智能分布式数据进行地理围栏开发的数量预计将越来越多。