ServiceImageTiledLayer QML Type

A base class for all image tiled layers that fetches map tiles from a remote service. More...

• List of all members, including inherited members

Properties

• credential : Credential
• requestConfiguration : RequestConfiguration
• tileUrlCallback : var
• url : url

Signals

• credentialChanged()
• requestConfigurationChanged()
• tileUrlCallbackChanged()

Methods

• void setTileUrl(TileKey tileKey, string url)

Detailed Description

This QML type supports the following default properties. A default property may be declared inside another declared object without being assigned explicitly to a property.

Note: the following default properties apply to all subclasses.

The properties fullExtent and tileInfo must be defined to create a ServiceImageTiledLayer.

Creating a custom service image tiled layer

When tiles are to be fetched from a remote service, a request is made to obtain the tile's URL based on the geographic location. The custom service image tiled layer must then supply the correct URL for the tile. The URL must be a valid online image URL. If the URL is not valid or if the image format does not match the tile info, ServiceImageTiledLayer will emit an error.

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

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

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

    // supply JavaScript callback to return specific tile URL
    tileUrlCallback: function(level, row, column) {
        var requestUrl = ("https://myTileServiceUrl/" + level +"/" + column + "/" + row + ".png");
        return requestUrl;
    }
}

Note: Network requesting, downloading images and rendering are done internally.

See also Cancelable, LayerContent, RemoteResource, Loadable, Envelope, TileInfo, TileInfo, and TileKey.

Property Documentation

Signal Documentation

Method Documentation