ArcGIS tiled layer (tile cache)

View in

C++

QML

View on GitHub

Sample viewer app

Load an offline copy of a tiled map service as a basemap.

screenshot

Use case

Constructing an ArcGISTiledLayer from a local tile package (.tpk & .tpkx) allows you to use that basemap tiled service when the application is offline. Dividing a raster into tiles allows the map to provide relevant tiles and level of detail to the user when panning and zooming. For example, when working in an environment that has no connectivity, this could provide access to a map for navigating your surroundings.

How to use the sample

Launch the app to view the "San Francisco offline tile package" as the basemap.

How it works

Create a TileCache, specifying the path to the local tile package.
Create an ArcGISTiledLayer with the tile cache.
Create a Basemap with the tiled layer.
Create a Map with the basemap and set it to a MapView.

Relevant API

ArcGISTiledLayer
Basemap
Map
TileCache

Offline Data

Read more about how to set up the sample's offline data here.

Link	Local Location
San Francisco Streets TPKX	`<userhome>`/ArcGIS/Runtime/Data/tpkx/SanFrancisco.tpkx

About the data

The map opens to a view of the city of San Francisco, CA. In a disconnected environment, this basemap tile service would be fully accessible to zoom and pan as if you were connected to a online service.

Additional information

ArcGISTiledLayer and TileCache supports both .tpk and .tpkx file formats.

Sample Code

TileCacheLayer.cpp

TileCacheLayer.h

TileCacheLayer.qml

Use dark colors for code blocksCopy
// [WriteFile Name=TileCacheLayer, Category=Layers]
// [Legal]
// Copyright 2020 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 "TileCacheLayer.h"

#include"ArcGISTiledLayer.h"
#include "Map.h"
#include "MapQuickView.h"
#include "TileCache.h"

#include <QDir>

#ifdef Q_OS_IOS
#include <QStandardPaths>
#endif // Q_OS_IOS

using namespace Esri::ArcGISRuntime;

// helper method to get cross platform data path
namespace
{
  QString defaultDataPath()
  {
    QString dataPath;

  #ifdef Q_OS_ANDROID
    dataPath = "/sdcard";
  #elif defined Q_OS_IOS
    dataPath = QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation);
  #else
    dataPath = QDir::homePath();
  #endif

    return dataPath;
  }
} // namespace

TileCacheLayer::TileCacheLayer(QObject* parent /* = nullptr */):
  QObject(parent)
{
  const QString fileLocation = QString("%1/ArcGIS/Runtime/Data/tpkx/SanFrancisco.tpkx").arg(defaultDataPath());
  TileCache* tileCache = new TileCache(fileLocation, this);
  ArcGISTiledLayer* tiledLayer = new ArcGISTiledLayer(tileCache, this);
  Basemap* basemap = new Basemap(tiledLayer, this);
  m_map = new Map(basemap, this);
  m_map->setMinScale(110000);
}

TileCacheLayer::~TileCacheLayer() = default;

void TileCacheLayer::init()
{
  // Register the map view for QML
  qmlRegisterType<MapQuickView>("Esri.Samples", 1, 0, "MapView");
  qmlRegisterType<TileCacheLayer>("Esri.Samples", 1, 0, "TileCacheLayerSample");
}

MapQuickView* TileCacheLayer::mapView() const
{
  return m_mapView;
}

// Set the view (created in QML)
void TileCacheLayer::setMapView(MapQuickView* mapView)
{
  if (!mapView || mapView == m_mapView)
    return;

  m_mapView = mapView;
  m_mapView->setMap(m_map);

  emit mapViewChanged();
}