Change the appearance of a feature layer with a renderer.
Use case
A feature layer hosted on ArcGIS Online has a preset renderer and will display in an ArcGIS Runtime application with that renderer. However, for example, the color associated with the original renderer may be unsuitable for a company with staff or clients who are color blind, or for presentation with a different set of basemap and operational layers. In these cases, the renderer on the feature layer's data can be set to a more suitable color.
How to use the sample
Use the button to change the renderer on the feature layer. The original renderer displays orange circles, the diameters of which are proportional to carbon storage of each tree. When the blue renderer in this sample is applied, it displays the location of the trees simply as blue points.
How it works
- Create a
ServiceFeatureTablefrom a URL. - Create a
FeatureLayerfrom the service feature table. - Create a new renderer (in this case, a
SimpleRenderer). - Change the feature layer's renderer using
FeatureLayer::setRenderer(SimpleRenderer).
Relevant API
- FeatureLayer::setRenderer
- ServiceFeatureTable
- SimpleRenderer
About the data
This sample displays a feature layer in Warren Wilson College, North Carolina, showing carbon storage of trees on campus. The size of each circle is proportional to that particular tree's carbon storage total.
Tags
feature layer, renderer, visualization
Sample Code
// [WriteFile Name=FeatureLayerChangeRenderer, 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 "FeatureLayerChangeRenderer.h"
#include "Map.h"
#include "MapQuickView.h"
#include "FeatureLayer.h"
#include "Basemap.h"
#include "SpatialReference.h"
#include "ServiceFeatureTable.h"
#include "Viewpoint.h"
#include "Envelope.h"
#include "SimpleLineSymbol.h"
#include "SimpleRenderer.h"
#include <QColor>
#include <QUrl>
using namespace Esri::ArcGISRuntime;
FeatureLayerChangeRenderer::FeatureLayerChangeRenderer(QQuickItem* parent) :
QQuickItem(parent)
{
}
FeatureLayerChangeRenderer::~FeatureLayerChangeRenderer() = default;
void FeatureLayerChangeRenderer::init()
{
qmlRegisterType<MapQuickView>("Esri.Samples", 1, 0, "MapView");
qmlRegisterType<FeatureLayerChangeRenderer>("Esri.Samples", 1, 0, "FeatureLayerChangeRendererSample");
}
void FeatureLayerChangeRenderer::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(Envelope(-13075816.4047166, 4014771.46954516, -13073005.6797177, 4016869.78617381, SpatialReference(102100))));
// Set map to map view
m_mapView->setMap(m_map);
// create the feature table
ServiceFeatureTable* featureTable = new ServiceFeatureTable(QUrl("https://sampleserver6.arcgisonline.com/arcgis/rest/services/PoolPermits/FeatureServer/0"), this);
// create the feature layer using the feature table
m_featureLayer = new FeatureLayer(featureTable, this);
connect(m_featureLayer, &FeatureLayer::loadStatusChanged, this, [this](LoadStatus loadStatus)
{
loadStatus == LoadStatus::Loaded ? m_initialized = true : m_initialized = false;
emit layerInitializedChanged();
});
// add the feature layer to the map
m_map->operationalLayers()->append(m_featureLayer);
}
bool FeatureLayerChangeRenderer::layerInitialized() const
{
return m_initialized;
}
void FeatureLayerChangeRenderer::changeRenderer()
{
// create a line symbol
SimpleLineSymbol* sls = new SimpleLineSymbol(SimpleLineSymbolStyle::Solid, QColor(0, 0, 255, 204), 2.0f, this);
// create a renderer with the symbol above
SimpleRenderer* simpleRenderer = new SimpleRenderer(sls, this);
// change the renderer with the renderer created above
m_featureLayer->setRenderer(simpleRenderer);
}