Feature layer query

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
// [WriteFile Name=FeatureLayerQuery, Category=Features]
// [Legal]
// Copyright 2016 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 "FeatureLayerQuery.h"

#include "Map.h"
#include "MapQuickView.h"
#include "FeatureLayer.h"
#include "Basemap.h"
#include "SpatialReference.h"
#include "ServiceFeatureTable.h"
#include "Viewpoint.h"
#include "Point.h"
#include "SimpleLineSymbol.h"
#include "SimpleFillSymbol.h"
#include "SimpleRenderer.h"
#include "QueryParameters.h"
#include "FeatureQueryResult.h"
#include "Feature.h"
#include "MapViewTypes.h"
#include "MapTypes.h"
#include "SymbolTypes.h"
#include "LayerListModel.h"
#include "FeatureIterator.h"

#include <QColor>
#include <QFuture>
#include <QList>
#include <QUuid>
#include <QUrl>

#include <memory>

using namespace Esri::ArcGISRuntime;

FeatureLayerQuery::FeatureLayerQuery(QQuickItem* parent) :
  QQuickItem(parent)
{
}

FeatureLayerQuery::~FeatureLayerQuery() = default;

void FeatureLayerQuery::init()
{
  qmlRegisterType<MapQuickView>("Esri.Samples", 1, 0, "MapView");
  qmlRegisterType<FeatureLayerQuery>("Esri.Samples", 1, 0, "FeatureLayerQuerySample");
}

void FeatureLayerQuery::componentComplete()
{
  QQuickItem::componentComplete();

  // find QML MapView component
  m_mapView = findChild<MapQuickView*>("mapView");
  m_mapView->setWrapAroundMode(WrapAroundMode::Disabled);

  // Create a map using the topographic basemap
  m_map = new Map(BasemapStyle::ArcGISTopographic, this);
  m_map->setInitialViewpoint(Viewpoint(Point(-11e6, 5e6, SpatialReference(102100)), 9e7));

  // Set map to map view
  m_mapView->setMap(m_map);

  // create the feature table
  m_featureTable = new ServiceFeatureTable(QUrl("https://services.arcgis.com/jIL9msH9OI208GCb/arcgis/rest/services/USA_Daytime_Population_2016/FeatureServer/0"), this);
  // create the feature layer using the feature table
  m_featureLayer = new FeatureLayer(m_featureTable, this);

  // line symbol for the outline
  SimpleLineSymbol* outline = new SimpleLineSymbol(SimpleLineSymbolStyle::Solid, QColor("black"), 2.0f, this);
  // fill symbol
  SimpleFillSymbol* sfs = new SimpleFillSymbol(SimpleFillSymbolStyle::Solid, QColor(255, 255, 0, 153), outline, this);
  // create the renderer using the symbology created above
  SimpleRenderer* renderer = new SimpleRenderer(sfs, this);
  // set the renderer for the feature layer
  m_featureLayer->setRenderer(renderer);
  m_featureLayer->setMaxScale(10000);

  // add the feature layer to the map
  m_map->operationalLayers()->append(m_featureLayer);

  connect(m_featureTable, &ServiceFeatureTable::loadStatusChanged, this, [this](LoadStatus loadStatus)
  {
    loadStatus == LoadStatus::Loaded ? m_initialized = true : m_initialized = false;
    emit layerInitializedChanged();
  });
}

bool FeatureLayerQuery::layerInitialized() const
{
  return m_initialized;
}

void FeatureLayerQuery::runQuery(const QString& stateName)
{
  // create a query parameter object and set the where clause
  QueryParameters queryParams;
  queryParams.setWhereClause(QString("STATE_NAME LIKE '" + formatStateNameForQuery(stateName) + "%'"));
  m_featureTable->queryFeaturesAsync(queryParams).then(this, [this](FeatureQueryResult* rawQueryResult)
  {
    auto queryResult = std::unique_ptr<FeatureQueryResult>(rawQueryResult);

    if (queryResult && !queryResult->iterator().hasNext())
    {
      m_queryResultsCount = 0;
      emit queryResultsCountChanged();
      return;
    }

    // clear any existing selection
    m_featureLayer->clearSelection();
    QList<Feature*> features;

    // iterate over the result object
    while (queryResult->iterator().hasNext())
    {
      Feature* feature = queryResult->iterator().next(this);
      // add each feature to the list
      features.append(feature);
    }

    // select the feature
    m_featureLayer->selectFeatures(features);
    // zoom to the first feature
    m_mapView->setViewpointGeometryAsync(features.at(0)->geometry(), 30);
    // set the count for QML property
    m_queryResultsCount = static_cast<int>(features.count());
    emit queryResultsCountChanged();
  });
}

QString FeatureLayerQuery::formatStateNameForQuery(const QString& stateName) const
{
  // format state names as expected by the service, for instance "Rhode Island"
  if (stateName.isEmpty())
    return QString();

  const QStringList words = stateName.split(" ", Qt::SkipEmptyParts);
  QStringList formattedWords;

  for (const QString& word : words)
  {
    QString formattedWord = word.toLower();
    formattedWord[0] = formattedWord[0].toUpper();
    formattedWords.append(formattedWord);
  }

  return QString(formattedWords.join(" "));
}

int FeatureLayerQuery::queryResultsCount() const
{
  return m_queryResultsCount;
}