QGIS/python/plugins/sextante/algs/AddTableField.py
2012-09-15 18:30:32 +03:00

61 lines
2.5 KiB
Python

from sextante.core.GeoAlgorithm import GeoAlgorithm
from sextante.outputs.OutputVector import OutputVector
from sextante.parameters.ParameterVector import ParameterVector
from qgis.core import *
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from sextante.parameters.ParameterString import ParameterString
from sextante.parameters.ParameterSelection import ParameterSelection
from sextante.core.QGisLayers import QGisLayers
import os
from PyQt4 import QtGui
class AddTableField(GeoAlgorithm):
OUTPUT_LAYER = "OUTPUT_LAYER"
INPUT_LAYER = "INPUT_LAYER"
FIELD_NAME = "FIELD_NAME"
FIELD_TYPE = "FIELD_TYPE"
TYPE_NAMES = ["Integer", "Float", "String"]
TYPES = [QVariant.Int, QVariant.Double, QVariant.String]
def getIcon(self):
return QtGui.QIcon(os.path.dirname(__file__) + "/../images/toolbox.png")
def defineCharacteristics(self):
self.name = "Add field to attributes table"
self.group = "Algorithms for vector layers"
self.addParameter(ParameterVector(self.INPUT_LAYER, "Input layer", ParameterVector.VECTOR_TYPE_ANY, False))
self.addParameter(ParameterString(self.FIELD_NAME, "Field name"))
self.addParameter(ParameterSelection(self.FIELD_TYPE, "Field type", self.TYPE_NAMES))
self.addOutput(OutputVector(self.OUTPUT_LAYER, "Output layer"))
def processAlgorithm(self, progress):
fieldtype = self.getParameterValue(self.FIELD_TYPE)
fieldname = self.getParameterValue(self.FIELD_NAME)
output = self.getOutputFromName(self.OUTPUT_LAYER)
vlayer = QGisLayers.getObjectFromUri(self.getParameterValue(self.INPUT_LAYER))
vprovider = vlayer.dataProvider()
allAttrs = vprovider.attributeIndexes()
vprovider.select( allAttrs )
fields = vprovider.fields()
fields[len(fields)] = QgsField(fieldname, self.TYPES[fieldtype])
writer = output.getVectorWriter(fields, vprovider.geometryType(), vprovider.crs() )
inFeat = QgsFeature()
outFeat = QgsFeature()
inGeom = QgsGeometry()
nFeat = vprovider.featureCount()
nElement = 0
while vprovider.nextFeature(inFeat):
progress.setPercentage(int((100 * nElement)/nFeat))
nElement += 1
inGeom = inFeat.geometry()
outFeat.setGeometry( inGeom )
atMap = inFeat.attributeMap()
outFeat.setAttributeMap( atMap )
outFeat.addAttribute( len(vprovider.fields()), QVariant() )
writer.addFeature( outFeat )
del writer