code: public void setLayer(VectorLayer layer) {
  		this.layer = layer;
  		Object value = layerSelect.getValue();
  		if (value == null || !value.equals(layer.getLabel())) {
  			layerSelect.setValue(layer.getLabel());
  		}
  		empty();
  	}
docs: Set a new layer onto which searching should happen.
  
  @param layer layer to search on