TdxMapLayers Class
A collection of map layers.
Declaration
TdxMapLayers = class(
TcxComponentCollection
)
Remarks
Map Control content is arranged into layers that can display different information, such as terrain, roads, routes, waypoints, etc.
Main API Members
The list below outlines key members of the TdxMapLayers
class. These members allow you to access and manage individual map layers.
Collection Management API Members
- Add
- Creates a new map layer of the required type and adds the layer to the collection.
- Clear
- Clears the map layer collection.
- Count
- Returns the number of map layers in the collection.
- Items
- Provides indexed access to map layers in the collection.
- Remove
- Removes an individual map layer from the collection.
General-Purpose API Members
- Assign
- Copies map layers between collections.
- BeginUpdate | EndUpdate
- Allow you to avoid excessive redraw operations during batch collection changes.
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:
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;
Direct TdxMapLayers Class Reference
The TdxCustomMapControl.Layers property references a TdxMapLayers
object.
Inheritance
TObject
TPersistent
TcxComponentCollection
TdxMapLayers
See Also