TdxMapLayerClass Type

A reference to a map layer class.

Declaration

delphi

TdxMapLayerClass = class of TdxMapLayer;

Referenced Class

Type	Description
TdxMapLayer

The base class for all map layer classes.

Remarks

You can use the TdxMapLayerClass type to refer to the following [TdxMapLayer] class descendants:

TdxMapImageTileLayerA map tile layer.TdxMapItemFileLayerAn item file layer.TdxMapItemLayerAn item layer.

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
C++

delphi

uses
  dxAzureMapImageryDataProvider; // 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;

cpp

#include "dxAzureMapImageryDataProvider.hpp" // 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
  }
}

Direct TdxMapLayerClass Type Reference

The TdxMapLayers.Add function accepts a TdxMapLayerClass value as the AItemClass parameter.