If you are not getting calls to your tileRequestHandler, yes, double check your AGSTileInfo and make sure you have created a layer of type AGSImageTiledLayer. There is a AGSServiceImageTiledLayer class has a different handler that is used to provide a URL for a tile.
Here is a some sample code which gets a a default AGSTileInfo and extent from one of the standard base maps, then uses that information to create a custom tiled layer.
```
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
//This will get the default tileInfo; it passes a completion handler
//which will create the custom layer and add it as a baseLayer to
//a new map.
defaultTileInfoWithCompletion { (tileInfo, fullExtent, error) in
//make sure we have no error and our tileInfo and fullExtent are OK
guard error == nil else { print("defaultTileInfo generated an error: \(error)"); return }
guard let tileInfo = tileInfo else { print("tileInfo is nil"); return }
guard let fullExtent = fullExtent else { print("fullExtent is nil"); return }
//creat the customLayer
let customLayer = AGSImageTiledLayer(tileInfo: tileInfo, fullExtent: fullExtent)
//Set tileRequestHandler, which gets called when the map needs a tile
customLayer.tileRequestHandler = { [weak customLayer] (tileKey: AGSTileKey) in
//In this sample, we're just responding with the data for a blue pushpin; for your own tiles,
//you would use the information in tileKey to return the correct tile data.
let image = UIImage(named: "BluePushpin")
customLayer?.respond(with: tileKey, data: UIImagePNGRepresentation(image!), error: nil)
}
//create a basemap, adding our customLayer as a baseLayer
let basemap = AGSBasemap()
basemap.baseLayers.add(customLayer)
//create the map and load it. You could also set it on a mapView, which would load it for you.
let map = AGSMap(basemap: basemap)
map.load(completion: { (error) in
guard error == nil else { print("Error loading map: \(error)"); return }
print("Map is loaded!")
})
self.myMap = map
}
}
//This method gets the default tileInfo from a simple basemap
//Because loading the baseLayer is asynchronous, a completion handler
//is provided; the handler will be called when the baseLayer is loaded
//
//Clients should create a tileInfo object using one of the AGSTileInfo constructors,
//based on your specific tile information.
func defaultTileInfoWithCompletion(_ completion: @escaping (_ tileInfo: AGSTileInfo?, _ fullExtent: AGSEnvelope?, _ error: Error?) -> Void) {
let basemap = AGSBasemap.lightGrayCanvas()
basemap.load { (error) in
guard error == nil else { print("basemap failed to load: \(error)"); return }
if let baseLayer = basemap.baseLayers[0] as? AGSArcGISTiledLayer {
baseLayer.load(completion: { (error) in
if error != nil {
completion(nil, nil, error)
return
}
let tileInfo = baseLayer.mapServiceInfo?.tileInfo
completion(tileInfo, baseLayer.fullExtent, nil)
})
}
}
}
```
Let us know if you're still having problems.
