ImageTiledLayer Class

CustomTiledLayer::CustomTiledLayer(const TileInfo& tileInfo, const Envelope& fullExtent, QObject* parent) :
  ImageTiledLayer(tileInfo, fullExtent, parent)
{
  connect(this, &CustomTiledLayer::tileRequest, this, [this](const TileKey& tileKey)
  {
    QString localUrl = tilesDataRoot() + QString("/tiledata/%1-%2-%3.jpg").arg(
          QString::number(tileKey.level()),
          QString::number(tileKey.row()),
          QString::number(tileKey.column()));

    QFile f(localUrl);
    if (!f.exists())
    {
      sendMessage(QString("Cannot find: %1").arg(localUrl));
      setNoDataTile(tileKey);
    }
    else if (!f.open(QIODevice::OpenModeFlag::ReadOnly))
    {
      sendMessage(QString("Cannot open: %1").arg(localUrl));
      setTileError(tileKey, QString("Cannot open: %1").arg(localUrl));
    }
    else
      setTileData(tileKey, f.readAll());
  });
}

Member Function Documentation

[since Esri::ArcGISRuntime 100.2] ImageTiledLayer::ImageTiledLayer(const Esri::ArcGISRuntime::TileInfo &tileInfo, const Esri::ArcGISRuntime::Envelope &fullExtent, QObject *parent = nullptr)

Creates an image tiled layer from the given tile metadata and the full extent.

• tileInfo - A tile info object.
• fullExtent - The full extent of the layer.
• parent - The optional parent QObject.

This function was introduced in Esri::ArcGISRuntime 100.2.

[override virtual] ImageTiledLayer::~ImageTiledLayer()

Destructor.

[signal, since Esri::ArcGISRuntime 100.2] void ImageTiledLayer::cancelTileRequest(const Esri::ArcGISRuntime::TileKey &tileKey)

Signal emitted when a tile request is canceled.

• tileKey - The key used to identify the specific tile.

This function was introduced in Esri::ArcGISRuntime 100.2.

Esri::ArcGISRuntime::NoDataTileBehavior ImageTiledLayer::noDataTileBehavior() const

Controls how a tile request that returns 'NoData' is resampled.

Zooming in can result in tile requests with no tiles at the requested level of detail. In this case, there are options that control what to display where the tile should be including:

• NoDataTileBehavior::UpSample - Resample the pixels from a lower level of detail tile. This can result in pixelation or blurriness. This is the default behavior for operational layers.
• NoDataTileBehavior::Blank - The 'NoData' pixels will show the raster picture as being blank (or disappearing). This is the default behavior for basemap reference layers.
• NoDataTileBehavior::Show - This will show the raster picture with the text 'No Data' stamped over it once you pass the lowest level-of-detail scale.

Note: Sometimes, to see the effect on the map when setting the noDataTileBehavior property, the Layer::maxScale value must also be explicitly set. The Layer::maxScale property may need to be smaller than the level-of-detail setting that was used to create the tiled images in ArcGIS Pro or ArcGIS Desktop. For example, consider an operational image tile layer showing forest cover that was created with the level-of-detail assumption that it was to be viewed above a scale of 5000 (meaning you will not see 'NoData' until you zoom closer to the Earth than a 5000 scale). However, you want to be able to zoom in closer to the Earth surface, say down to 3000 or 300. By setting the Layer::maxScale property to a number smaller than 5000, you will be able to zoom in closer to the Earth and see the effects of changing the noDataTileBehavior enumerations.

See also setNoDataTileBehavior().

[virtual, since Esri::ArcGISRuntime 100.1] void ImageTiledLayer::setAttribution(const QString &attribution)

Sets the attribution string for the image tiled layer.

• attribution - The attribution string.

This function was introduced in Esri::ArcGISRuntime 100.1.

[protected, since Esri::ArcGISRuntime 100.2] void ImageTiledLayer::setNoDataTile(const Esri::ArcGISRuntime::TileKey &tileKey)

Specifies that there is no data corresponding to a tileKey.

This function was introduced in Esri::ArcGISRuntime 100.2.

See also ImageTiledLayer::setTileData.

void ImageTiledLayer::setNoDataTileBehavior(Esri::ArcGISRuntime::NoDataTileBehavior noDataTileBehavior)

Sets the noDataTileBehavior to noDataTileBehavior.

See also noDataTileBehavior.

[protected, since Esri::ArcGISRuntime 100.2] void ImageTiledLayer::setTileData(const Esri::ArcGISRuntime::TileKey &tileKey, const QByteArray &data)

Sets data corresponding to a tileKey.

This function was introduced in Esri::ArcGISRuntime 100.2.

[protected, since Esri::ArcGISRuntime 100.2] void ImageTiledLayer::setTileError(const Esri::ArcGISRuntime::TileKey &tileKey, const QString &error)

Sets an error corresponding to a tileKey.

This function was introduced in Esri::ArcGISRuntime 100.2.

Esri::ArcGISRuntime::TileInfo ImageTiledLayer::tileInfo() const

Returns the tiling scheme information for this layer.

The value of tileInfo cannot be changed after this layer is loaded.

[signal, since Esri::ArcGISRuntime 100.2] void ImageTiledLayer::tileRequest(const Esri::ArcGISRuntime::TileKey &tileKey)

Signal emitted when a tile is requested.

• tileKey - The key used to identify the specific tile.

This function was introduced in Esri::ArcGISRuntime 100.2.