TdxMapImageTileLayer.ProviderClass Property

Specifies the active map tile provider type.

Declaration

property ProviderClass: TdxMapControlImageTileProviderClass read; write;

Property Value

Type	Description
TdxMapControlImageTileProviderClass	The reference to the active map tile provider class. Refer to the Remarks section for the full list of supported tile provider types.

Remarks

Use the ProviderClass property to switch between available data providers for the map tile layer. To configure data provider settings, use the Provider property.

Available Map Tile Providers

You can assign references to the following classes to the ProviderClass property to select the corresponding tile provider:

TdxMapControlAzureMapImageryDataProvider

Loads map tiles from Azure Maps servers.

TdxMapControlOpenStreetMapImageryDataProvider

Loads map tiles from the OpenStreetMap service.

Tile Provider Selection at Design Time

You can use the Object Inspector to select any available tile data provider at design time. Select an image tile layer, click the Provider node’s drop-down button and select the required data provider in the menu.

Property Setter Behavior

The ProviderClass property setter updates Provider and ProviderClassName property values according to the selected tile data provider type.

Code Example: Add a Tile Map Layer and Load Azure Maps Data

The following code example implements a procedure that accepts an Azure Maps account key, creates and configures a map tile layer, and loads data:

Delphi

uses
  dxAzureMapImageryDataProvider;  // This unit declares TdxMapControlAzureMapImageryDataProvider
// ...

procedure TMyForm.AddAzureMapLayer(const AAzureKey: string);
var
  ATileLayer: TdxMapImageTileLayer;
  AProvider: TdxMapControlAzureMapImageryDataProvider;
begin
  ATileLayer := dxMapControl1.Layers.Add(TdxMapImageTileLayer) as TdxMapImageTileLayer;
  ATileLayer.ProviderClass := TdxMapControlAzureMapImageryDataProvider;
  AProvider := ATileLayer.Provider as TdxMapControlAzureMapImageryDataProvider;
  AProvider.BeginUpdate;  // Initiates the following batch change
  try
    AProvider.AzureKey := AAzureKey;  // Assigns the Azure account key
    AProvider.Tileset := TdxAzureMapTileset.Satellite;  // Changes the default tileset
    AProvider.MaxParallelConnectionCount := 8;  // Explicitly defines the number of parallel connections
  finally
    AProvider.EndUpdate;  // Calls EndUpdate regardless of the batch operation's success
  end;
end;

C++

#include "dxAzureMapImageryDataProvider.hpp"  // This header declares TdxMapControlAzureMapImageryDataProvider
// ...

void __fastcall TMyForm::AddAzureMapLayer(const UnicodeString &AAzureKey)
{
  TdxMapLayer *ALayer;
  TdxMapImageTileLayer *ATileLayer;
  TdxMapControlAzureMapImageryDataProvider *AProvider;

  ALayer = dxMapControl1->Layers->Add(__classid(TdxMapImageTileLayer));
  ATileLayer = dynamic_cast<TdxMapImageTileLayer*>(ALayer);
  ATileLayer->ProviderClass = __classid(TdxMapControlAzureMapImageryDataProvider);
  AProvider = dynamic_cast<TdxMapControlAzureMapImageryDataProvider*>(ATileLayer->Provider);
  AProvider->BeginUpdate();  // Initiates the following batch change
  try
  {
    AProvider->AzureKey = AAzureKey;  // Assigns the Azure account key
    AProvider->Tileset = TdxAzureMapTileset::Satellite;  // Changes the default tileset
    AProvider->MaxParallelConnectionCount = 8;  // Explicitly defines the number of parallel connections
  }
  __finally
  {
    AProvider->EndUpdate();  // Calls EndUpdate regardless of the batch operation's success
  }
}

Related Compiled Demo

To see map tile layers with all supported information providers in action, run the Mapping demo in the VCL Demo Center installed with compiled DevExpress demos. Click the Data Providers item in the side bar to the left and switch between available data providers in the Ribbon UI.

Download: Compiled VCL Demos

Tip

You can find full source code for installed complied Map Control demos in the following folder:

%PUBLIC%\Public Documents\DevExpress VCL Demos\MegaDemos\Product Demos\ExpressMapControl