Find a place

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Sample viewer app

Find places of interest near a location or within a specific area.

screenshot

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

  1. Create a LocatorTask using a URL to a locator service.
  2. 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 of GeocodeResults.
    • Use the displayLocation from one of the results to build an Envelope to search within.
  3. 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 of SuggestResults.
    • The SuggestResult will have a label to display in the search suggestions list.
  4. 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 of GeocodeResults.
    • Display the places of interest using the results' displayLocations.

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

FindPlace.cppFindPlace.cppFindPlace.hSearchBox.qmlSearchButton.qmlSuggestionView.qmlFindPlace.qml
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// [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;
}

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