Find places of interest near a location or within a specific area.
Use case
When getting directions or looking for nearby places, users may only know what the place has ("food"), the type of place ("gym"), or the generic place name ("Starbucks"), rather than the specific address. You can get suggestions and locations for these places of interest (POIs) using a natural language query. Additionally, you can filter the results to a specific area.
How to use the sample
Choose a place of interest to enter in the first field and an area to search within in the second field. Click the magnifying glass or hit enter to search and show the results of the query on the map from your current extent. Click on a result pin to show its name and address. If you pan away from the result area, a "Redo search in this area" button will appear. Click it to query again for the currently viewed area on the map.
How it works
- Create a
LocatorTask
using a URL to a locator service. - Find the location for an address (or city name) to build an envelope to search within:
- Create
GeocodeParameters
. - Add return fields to the parameters'
resultAttributeNames
collection. Only add a single "*" option to return all fields. - Call
locatorTask::geocodeWithParameters(locationQueryString, geocodeParameters)
to get a list ofGeocodeResult
s. - Use the
displayLocation
from one of the results to build anEnvelope
to search within.
- Create
- Get place of interest (POI) suggestions based on a place name query:
- Create
SuggestParameters
. - Add "POI" to the parameters'
categories
collection. - Call
locatorTask::suggestions()
to get a list ofSuggestResults
. - The
SuggestResult
will have alabel
to display in the search suggestions list.
- Create
- Use one of the suggestions or a user-written query to find the locations of POIs:
- Create
GeocodeParameters
. - Set the parameters'
searchArea
to the envelope. - Call
locatorTask::geocodeWithParameters(suggestionLabelOrPlaceQueryString, geocodeParameters)
to get a list ofGeocodeResult
s. - Display the places of interest using the results'
displayLocation
s.
- Create
Relevant API
- GeocodeParameters
- GeocodeResult
- LocatorTask
- SuggestParameters
- SuggestResult
About the data
This sample uses the World Geocoding Service.
Tags
businesses, geocode, locations, locator, places of interest, POI, point of interest, search, suggestions
Sample Code
// [WriteFile Name=FindPlace, Category=Search]
// [Legal]
// Copyright 2017 Esri.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// [Legal]
#ifdef PCH_BUILD
#include "pch.hpp"
#endif // PCH_BUILD
#include "FindPlace.h"
#include "CalloutData.h"
#include "Map.h"
#include "MapQuickView.h"
#include "GraphicsOverlay.h"
#include "GeocodeResult.h"
#include "GeoElement.h"
#include "GeometryEngine.h"
#include "PictureMarkerSymbol.h"
#include "IdentifyGraphicsOverlayResult.h"
#include "Point.h"
#include "Envelope.h"
#include "SimpleRenderer.h"
#include "LocatorTask.h"
#include "LocationDisplay.h"
#include "SuggestListModel.h"
#include <QUrl>
using namespace Esri::ArcGISRuntime;
FindPlace::FindPlace(QQuickItem* parent /* = nullptr */):
QQuickItem(parent)
{
}
FindPlace::~FindPlace()
{
m_mapView->locationDisplay()->stop();
}
void FindPlace::init()
{
// Register the map view for QML
qmlRegisterType<MapQuickView>("Esri.Samples", 1, 0, "MapView");
qmlRegisterType<FindPlace>("Esri.Samples", 1, 0, "FindPlaceSample");
qmlRegisterUncreatableType<CalloutData>("Esri.Samples", 1, 0, "CalloutData", "CalloutData is an uncreatable type");
qmlRegisterUncreatableType<QAbstractListModel>("Esri.Samples", 1, 0, "AbstractListModel", "AbstractListModel is uncreateable");
}
void FindPlace::componentComplete()
{
QQuickItem::componentComplete();
// find QML MapView component
m_mapView = findChild<MapQuickView*>("mapView");
// Create a map using the topographic basemap
m_map = new Map(BasemapStyle::ArcGISTopographic, this);
// Set map to map view
m_mapView->setMap(m_map);
// create the locator
createLocator();
// add the graphics overlay
addGraphicsOverlay();
// initialize callout
m_mapView->calloutData()->setVisible(false);
m_calloutData = m_mapView->calloutData();
// connect mapview signals
connectSignals();
}
void FindPlace::connectSignals()
{
connect(m_mapView, &MapQuickView::drawStatusChanged, this, [this](DrawStatus drawStatus)
{
if (drawStatus != DrawStatus::Completed || m_mapView->locationDisplay()->isStarted())
return;
// turn on the location display
m_mapView->locationDisplay()->setAutoPanMode(LocationDisplayAutoPanMode::Recenter);
m_mapView->locationDisplay()->start();
});
connect(m_mapView, &MapQuickView::mousePressed, this, [this](QMouseEvent& /*event*/)
{
emit hideSuggestionView();
});
connect(m_mapView, &MapQuickView::viewpointChanged, this, [this]()
{
emit hideSuggestionView();
if (m_graphicsOverlay->graphics()->size() > 0)
emit showExtentButton();
});
// perform an identify operation on mouse clicked
connect(m_mapView, &MapQuickView::mouseClicked, this, [this](QMouseEvent& e)
{
emit hideCallout();
m_mapView->identifyGraphicsOverlay(m_graphicsOverlay, e.x(), e.y(), 5, false, 1);
});
// handle the result once identify completes
connect(m_mapView, &MapQuickView::identifyGraphicsOverlayCompleted, this, [this](QUuid, IdentifyGraphicsOverlayResult* result)
{
if (result->graphics().length() == 0)
return;
// display the callout with the identify result
Graphic* graphic = result->graphics().at(0);
m_calloutData->setGeoElement(graphic);
m_calloutData->setTitle(graphic->attributes()->attributeValue("ShortLabel").toString());
m_calloutData->setDetail(graphic->attributes()->attributeValue("Place_addr").toString());
emit showCallout();
});
}
void FindPlace::addGraphicsOverlay()
{
// add a graphics overlay to the mapview
m_graphicsOverlay = new GraphicsOverlay(this);
m_mapView->graphicsOverlays()->append(m_graphicsOverlay);
// create a renderer for graphics representing geocode results
PictureMarkerSymbol* pinSymbol = new PictureMarkerSymbol(QUrl("qrc:/Samples/Search/FindPlace/red_pin.png"), this);
pinSymbol->setHeight(36);
pinSymbol->setWidth(19);
pinSymbol->setOffsetY(pinSymbol->height() / 2);
SimpleRenderer* simpleRenderer = new SimpleRenderer(pinSymbol, this);
m_graphicsOverlay->setRenderer(simpleRenderer);
}
void FindPlace::createLocator()
{
// create a locator task that uses the world geocoding service
// an ArcGIS Developer API key is required to utilize the world geocoding service
m_locatorTask = new LocatorTask(QUrl("https://geocode-api.arcgis.com/arcgis/rest/services/World/GeocodeServer"), this);
// set the suggestions Q_PROPERTY
m_suggestListModel = m_locatorTask->suggestions();
emit suggestionsChanged();
// connect to the signal for when the geocode completes
connect(m_locatorTask, &LocatorTask::geocodeCompleted, this, [this](QUuid, const QList<GeocodeResult>& results)
{
// if we are converting the location string to a Point, re-geocode with that information,
// and don't add any graphics to the map
if (m_isSearchingLocation)
{
m_isSearchingLocation = false;
if (results.length() == 0)
return;
GeocodeResult topLocation = results.at(0);
geocodePOIs(m_poiSearchText, topLocation.displayLocation());
return;
}
// create graphics for each geocode result
if (results.length() == 0)
return;
m_graphicsOverlay->graphics()->clear();
// delete parent if it exists
if (m_graphicParent)
{
delete m_graphicParent;
m_graphicParent = nullptr;
}
m_graphicParent = new QObject(this);
Geometry bbox;
for (const GeocodeResult& result : results)
{
Graphic* graphic = new Graphic(result.displayLocation(), result.attributes(), m_graphicParent);
m_graphicsOverlay->graphics()->append(graphic);
// create bounding box so we can set the viewpoint at the end
if (bbox.isEmpty())
bbox = graphic->geometry();
else
bbox = GeometryEngine::unionOf(bbox, graphic->geometry());
}
// zoom to the bounding box
m_mapView->setViewpointGeometry(bbox, 40);
});
}
void FindPlace::setPoiTextHasFocus(bool hasFocus)
{
if (m_poiTextHasFocus == hasFocus)
return;
m_poiTextHasFocus = hasFocus;
// create and update the suggestion parameters
SuggestParameters suggestParams;
// the Points of Interest suggestions should use the POI category, and the location
// suggestions should use the Populated Place category as filters
QStringList categories;
m_poiTextHasFocus ? categories << "POI" : categories << "Populated Place";
suggestParams.setCategories(categories);
suggestParams.setMaxResults(5);
if (m_locatorTask)
m_locatorTask->suggestions()->setSuggestParameters(suggestParams);
emit poiTextHasFocusChanged();
}
// set the suggestion search text to fetch suggestions
void FindPlace::setSuggestionsText(const QString& searchText)
{
if (!m_suggestListModel)
return;
SuggestListModel* suggestListModel = dynamic_cast<SuggestListModel*>(m_suggestListModel);
if (!suggestListModel)
return;
suggestListModel->setSearchText(searchText);
}
// geocode without any spatial filter
void FindPlace::geocodePOIs(const QString& poi)
{
m_poiSearchText = poi;
GeocodeParameters params = createParameters();
m_locatorTask->geocodeWithParameters(poi, params);
}
// use extent to filter the geocode results
void FindPlace::geocodePOIs(const QString& poi, SearchMode mode)
{
m_poiSearchText = poi;
GeocodeParameters params = createParameters();
// If the Mode is CurrentLocation, use the Location Display as preferred search location
if (mode == SearchMode::CurrentLocation)
{
params.setPreferredSearchLocation(m_mapView->locationDisplay()->location().position());
params.setOutputSpatialReference(m_mapView->locationDisplay()->location().position().spatialReference());
m_locatorTask->geocodeWithParameters(m_poiSearchText, params);
}
// If the Mode is BoundingGeometry, use the MapView's current viewpoint as the search area
else
{
GeocodeParameters params = createParameters();
Geometry extent = m_mapView->currentViewpoint(ViewpointType::BoundingGeometry).targetGeometry();
params.setSearchArea(extent);
params.setOutputSpatialReference(extent.spatialReference());
m_locatorTask->geocodeWithParameters(m_poiSearchText, params);
}
}
// use a point as a preferred search location for the geocode results
void FindPlace::geocodePOIs(const QString& poi, const Point& location)
{
m_poiSearchText = poi;
GeocodeParameters params = createParameters();
params.setPreferredSearchLocation(location);
params.setOutputSpatialReference(location.spatialReference());
m_locatorTask->geocodeWithParameters(m_poiSearchText, params);
}
// use a location string as a preferred search location for the geocode results
void FindPlace::geocodePOIs(const QString& poi, const QString& location)
{
if (location == m_currentLocationText)
{
geocodePOIs(poi, SearchMode::CurrentLocation);
return;
}
m_poiSearchText = poi;
GeocodeParameters params = createParameters();
m_isSearchingLocation = true;
m_locatorTask->geocodeWithParameters(location, params);
}
// create base geocode parameters
GeocodeParameters FindPlace::createParameters()
{
GeocodeParameters params;
params.setResultAttributeNames(QStringList{"*"});
params.setMaxResults(50);
params.setMinScore(75.0);
return params;
}