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A Geocoding Journey, a Wanderlust of Addresses and Coordinates

Popularity:244 ℃/2024-08-12 12:00:44

With the popularity of mobile devices and the development of location-based services, when using navigation and location search, users expect the location provided by apps to be accurate, and they also expect apps to provide personalized and localized services based on the location, e.g., to share location information on social media or to help with the intelligent networked management of home devices. To get an accurate location, latitude and longitude are the precise coordinates to determine the location of each place, but the use of coordinates to describe a location is accurate but not intuitive, and is not user-friendly.

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HarmonyOS SDKlocation service(Location Kit) providesGeocoding Transformation and Reverse Geocoding Transformation CapabilitiesThe forward geocoding transformation capability converts geographic descriptions into specific coordinates, and the reverse geocoding transformation capability converts coordinates into geographic descriptions. In practice, the inter-conversion of forward and reverse geocoding is important as users may be more familiar and accustomed to using addresses or place names to describe a location rather than latitude and longitude coordinates; mapping applications and navigation systems often use forward geocoding to convert addresses to geographic coordinates for accurate display of a location on a map or for route planning.

For example, when a user enters a delivery address when placing an order with a takeout app, forward geocoding converts the address entered by the user into latitude and longitude coordinates, which facilitates the app to mark the user's exact location on the map and provide the user with information about the neighboring merchants. Meanwhile, inverse geocoding converts the latitude and longitude coordinates into detailed address information so that the app can provide accurate delivery address to the merchants.

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In addition to daily life scenarios, forward and reverse geocoding supports the development of a wide range of commercial and technological application scenarios. In marketing, forward geocoding is used to accurately locate target markets, such as optimizing marketing strategies based on geographic location data in advertising to attract more local customers; reverse geocoding helps enterprises understand the geographic distribution of their customers, optimize the store layout or service coverage area, and improve the marketing effect and quality of customer service. In intelligent transportation and city management, city managers can use forward geocoding services to collect and analyze traffic flow data to optimize road design and traffic planning; while reverse geocoding can quickly determine the best route or resource allocation based on the geographic coordinates of the incident location when responding to emergency services.

To summarize, positive inverse geocoding is widely used in many applications, such as online maps, travel navigation, logistics and distribution and so on. Through positive inverse geocoding technology, geolocation information can be combined with actual scenes to provide more intelligent and convenient services.

development step

1. import geoLocationManager module, all the functional APIs related to geocoding transformation & inverse geocoding transformation ability, are provided through this module.

import { geoLocationManager } from '@';

2. Query the availability of geocoding and reverse geocoding services.

Call isGeoServiceAvailable to query whether the geocoding and inverse geocoding service is available, if the service is available then continue to step 3. if the service is not available, it means that the device does not have the capability of geocoding and inverse geocoding, please do not use the related interface.

import { geoLocationManager } from '@';
import { BusinessError } from '@'
try {
    let isAvailable = ();
} catch (err) {
        ("errCode:" + (err));
}

3. Getting Conversion Results

Call getAddressesFromLocation to convert coordinates into geolocation information. The application can get the coordinates matching thisGeoAddress (geocoded address information)list, the application can read the corresponding parameter data according to the actual usage requirements.

let reverseGeocodeRequest: = {"latitude": 31.12, "longitude": 121.11, "maxItems": 1};
try {
    (reverseGeocodeRequest, (err, data) => {
        if (err) {
            ('getAddressesFromLocation err: ' + (err));
        } else {
            ('getAddressesFromLocation data: ' + (data));
        }
    });
} catch (err) {
    ("errCode:" + (err));
}

Call getAddressesFromLocationName to convert the location description to coordinates.

let geocodeRequest: = {"description": "Pudong New District, Shanghaixxkindxxhorn (wind instrument)", "maxItems": 1};
try {
    (geocodeRequest, (err, data) => {
        if (err) {
            ('getAddressesFromLocationName err: ' + (err));
        } else {
            ('getAddressesFromLocationName data: ' + (data));
        }
    });
} catch (err) {
    ("errCode:" + (err));
}

The application can obtain a list of GeoAddress (geocoded address information) matching the location description, which contains the corresponding coordinate data.

If a location description needs to be queried for a request that may have multiple locations renamed, GeoCodeRequest can be set up to efficiently get the exact results desired by setting a latitude and longitude range.

By accessing ortho-reverse geocoding technology, developers can provide more accurate and intelligent geolocation data management and analysis functions for various application scenarios to optimize service efficiency and enhance user experience, as well as to support the needs of business decision-making and urban development planning.

Learn more >>

interviewsLocation Services Alliance Official Website

gainLocation Services Development Guidance Document