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ImageTiledLayer QML Type

A base class for layers that display cached maps. More...

Import Statement: import Esri.ArcGISRuntime 100.9
Since: Esri.ArcGISRuntime 100.0
Inherits:

ImageAdjustmentLayer

Inherited By:

ArcGISTiledLayer, ServiceImageTiledLayer, and WmtsLayer

Properties

Signals

Detailed Description

ImageTiledLayer defines a base class for layers that display tiled map services and cached image services. This is an abstract class that can be derived in a custom class to implement a local tile data scheme. To implement a custom ImageTiledLayer, for example to load your own local tile data, you should derive from this type and supply the data for each tile as it is requested. You would typically work with one or more sub-classes of this class.

Creating a custom ImageTiledLayer

When tiles must be displayed, a request is made to request the tile corresponding to a given tile key - based on the geographic location. The custom image tiled layer must then supply a valid URL for a local tile image.

The tileInfo property defines the format of requested images (image format, DPI, width and height), the limits of extent, and scale factor for requests.

You can supply a JavaScript callback function for the tileCallback property which defines how the local URL for a given tile request should be formed:

ImageTiledLayer {
    id: customTiledLayer
    fullExtent: Envelope { ... }
    tileInfo: TileInfo { ... }

    // supply JavaScript callback to return specific tile
    tileCallback: function(level, row, column) {
        var localileUrl = "file:///local/path/" + level + "/" + row + "/" + column + ".png");
        return localileUrl;
    }
}

See also Cancelable, LayerContent, and Loadable.

Property Documentation

attribution : string

The attribution text that should be displayed with the layer.

This property was introduced in Esri.ArcGISRuntime 100.1.


fullExtent : Envelope

The full extent of the layer.

This property was introduced in Esri.ArcGISRuntime 100.2.


noDataTileBehavior : Enums.NoDataTileBehavior

the NoDataTileBehavior for the layer.

Determines 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.

Below are the default values for a loaded layer.

Layer SituationDefault Value
Unbound (not added to the map/scene)Enums.NoDataTileBehaviorUpSample
Basemap reference layerEnums.NoDataTileBehaviorBlank
Basemap base layerEnums.NoDataTileBehaviorUpSample
Map operational layerEnums.NoDataTileBehaviorUpSample

tileCallback : var

The callback function that is called when a tile is requested.

The callback can make use of 3 JavaScript arguments and should return an URL to local file, or a component:

  • level.
  • row.
  • column.

This property was introduced in Esri.ArcGISRuntime 100.2.

See also TileKey.


tileInfo : TileInfo

Defines the image format and limits for request.

This property is populated after the layer loads.

This property was introduced in Esri.ArcGISRuntime 100.2.


Signal Documentation

fullExtentChanged()

Emitted when the fullExtent property changes.

Note: The corresponding handler is onFullExtentChanged.

This signal was introduced in Esri.ArcGISRuntime 100.2.


noDataTileBehaviorChanged()

Emitted when the noDataTileBehavior property changes.

Note: The corresponding handler is onNoDataTileBehaviorChanged.


tileCallbackChanged()

Emitted when the tileCallback property changes.

Note: The corresponding handler is onTileCallbackChanged.

This signal was introduced in Esri.ArcGISRuntime 100.2.


tileInfoChanged()

Emitted when the tileInfo property changes.

Note: The corresponding handler is onTileInfoChanged.



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