QGIS function

getIntersects.py

"""
Define new functions using @qgsfunction. feature and parent must always be the
last args. Use args=-1 to pass a list of values as arguments
"""

from qgis.core import *
from qgis.gui import *

@qgsfunction(args='auto', group='GCFunctions')
def GetIntersectGeoms(layer_name, field_name, feature, parent):
  """
  <h4>Syntax</h4>
  <p>GetIntersectGeoms(<i>layer_name,field_name</i>)</p>
  <h4>Arguments</h4>
  <p><i>layer_name</i> = Nome da layer que voce deseja verificar a ocorrencia de intersecao</p>
  <p><i>field_name</i> = Nome da coluna que deseja mostrar</p>
  <h4>Example</h4>
  GetIntersectGeoms('myLayerName', 'myFieldName')
  """
  layer_poly = None
  try:
	  layer_poly = QgsMapLayerRegistry.instance().mapLayersByName(layer_name)[0]  
	  polygons_selected = []
	  for feat in layer_poly.getFeatures():  
		  if feature.geometry().intersects(feat.geometry()):
			  polygons_selected.append(feat[field_name])
	  return ',\n'.join(sorted(polygons_selected))
  except IndexError:
	  return 'Layer nao encontrada'