How can I get Location of a DiscoveryResult when executing search suggestion? - here-api

Question

I'm using android SDK implement the search suggestion, code looks like below:
private void performSearch(CharSequence searchTerm) {
try {
DiscoveryRequest request = new SearchRequest( searchTerm.toString())
.setSearchCenter( mMap.getCenter() )
.setCollectionSize( 10 );
ErrorCode error = request.execute( mSearchRequestListener );
if ( error != ErrorCode.NONE ) {
Log.i( TAG, "Here API place search error: " + error.name() );
mSearchAdapter.notifyDataSetInvalidated();
}
} catch ( IllegalArgumentException ex ) {
Log.i( TAG, "Here API place search exception: " +
ex.getMessage() != null ? ex.getMessage() : "" );
mSearchAdapter.notifyDataSetInvalidated();
}
}
private ResultListener<DiscoveryResultPage> mSearchRequestListener =
new ResultListener<DiscoveryResultPage>() {
#Override
public void onCompleted(DiscoveryResultPage data, ErrorCode error) {
if ( error != ErrorCode.NONE ) {
Log.i( TAG, "Here API place search error: " + error.name() );
mSearchAdapter.notifyDataSetInvalidated();
return;
}
Log.d(TAG, "mSearchRequestListener.onCompleted: count=" + data.getItems().size() );
mResultList = new ArrayList<DiscoveryResult>( data.getItems());
String vicinity = mResultList.get(0).getVicinity();
//String location = ?
mSearchAdapter.notifyDataSetChanged();
}
};
How can I get the Location of a DiscoveryResult after I get DiscoveryResult list? It seems I didn't find this property in DiscoveryResult object. I need to add this location to my RoutePlan to calculate a route.
RoutePlan routePlan = new RoutePlan();
routePlan.addWaypoint(currentGeoCoordinate);
routePlan.addWaypoint(destGeoCoordinate);
routeManager.calculateRoute( routePlan, mRouteManagerListener );
I have a workaround for this in my code. After I get vicinity, I make a request at http://geocoder.cit.api.here.com/6.2/geocode.json?searchtext=" + vicinity + "gen=9"; to get the response. There is a Location property in response of this request. the disadvantage is I need to make a request to get location every time. Any suggestion to get the location without making a request to server?
Thanks in advance.

Answer 1

The data in the DiscoveryResultPage can be of several types, and you should sheck for the right type.
See documentation here:
https://developer.here.com/mobile-sdks/documentation/android-hybrid-plus/topics/places.html
The important part:
Calling DiscoveryResultPage.getItems(), returns a List containing one
of the following types of objects, which are DiscoveryResult
instances. DiscoveryResult is a collection of Link subtypes.
PlaceLink - Represents discovery information about a Place. The
PlaceLink contains a brief summary about a place. Details about a
place are available from the Place that the PlaceLink references.
DiscoveryLink - Represents a discovery-related API link used to
retrieve additional DiscoveryResultPage. This type of Link can be a
result item in an Explore or Here type of search. The DiscoveryLink
references refined discovery requests resulting in more specific
results. For example, the DiscoveryLink may link to a discovery
request to search for 'Eat & Drink', 'Going Out', 'Accommodation', and
so on. Since there may be new types of Link items in the future, it is
recommended that each type of DiscoveryResult be checked before it is
used (as shown in the following code snippet).
That means practically, that you iterate over data and check for the types like this:
// Implement a search result listener
ResultListener<DiscoveryResultPage> searchListener = new ResultListener<DiscoveryResultPage>() {
#Override
public void onCompleted(DiscoveryResultPage results, ErrorCode error) {
if (error == ErrorCode.NONE) {
// The results is a DiscoveryResultPage which represents a
// paginated collection of items.
List<DiscoveryResult> items = results.getItems();
// Iterate through the found place items.
for (DiscoveryResult item : items) {
// A Item can either be a PlaceLink (meta information
// about a Place) or a DiscoveryLink (which is a reference
// to another refined search that is related to the
// original search; for example, a search for
// "Leisure & Outdoor").
if (item.getResultType() == ResultType.PLACE) {
PlaceLink placeLink = (PlaceLink) item;
// PlaceLink should be presented to the user, so the link can be
// selected in order to retrieve additional details about a place
// of interest.
...
} else if (item.getResultType() == ResultType.DISCOVERY) {
DiscoveryLink discoveryLink = (DiscoveryLink) item;
// DiscoveryLink can also be presented to the user.
// When a DiscoveryLink is selected, another search request should be
// performed to retrieve results for a specific category.
...
}
}
} else {
// Handle search request error.
}
}
};
or only get the PlaceLink items directly like that:
public void onCompleted(DiscoveryResultPage data, ErrorCode error) {
List<PlaceLink> results = data.getPlaceLinks(); // we are only interested in PlaceLinks
if (results.size() > 0) {
for (PlaceLink result : results) {
// do something with the PlaceLink item
}
} else {
// handle empty result case
}
The PlaceLink object then has all the methods you would except, also getPosition() or getDistance() that you can use for putting results on the map or calculate a route.