SymbolLayer constructor
      
      SymbolLayer({ 
    
    
- required String id,
 - String? metadata,
 - dynamic source,
 - String? sourceLayer,
 - num? minZoom,
 - num? maxZoom,
 - dynamic filter,
 - SymbolLayout? layout,
 - SymbolPaint? paint,
 
Implementation
SymbolLayer({
  required this.id,
  this.metadata,
  this.source,
  this.sourceLayer,
  this.minZoom,
  this.maxZoom,
  this.filter,
  this.layout,
  this.paint,
});