Nyall Dawson 06c4b07222 [processing] Use layer crs/fields instead of provider crs/fields
Since the layer has more complete knowledge of the crs (ie, when
provider could not determine crs and user has selected it from
the list), and also better knowledge of layer fields (virtual
fields, joined fields) we should use these rather than the
provider methods.
2016-08-05 06:28:49 +10:00

123 lines
4.8 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
Gridify.py
---------------------
Date : May 2010
Copyright : (C) 2010 by Michael Minn
Email : pyqgis at michaelminn dot com
***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************
"""
__author__ = 'Michael Minn'
__date__ = 'May 2010'
__copyright__ = '(C) 2010, Michael Minn'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
import os
from qgis.PyQt.QtGui import QIcon
from qgis.PyQt.QtCore import QVariant
from qgis.core import QgsFields, QgsVectorLayer
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
from processing.core.parameters import ParameterMultipleInput
from processing.core.outputs import OutputVector
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
class Merge(GeoAlgorithm):
LAYERS = 'LAYERS'
OUTPUT = 'OUTPUT'
def getIcon(self):
return QIcon(os.path.join(pluginPath, 'images', 'ftools', 'merge_shapes.png'))
def defineCharacteristics(self):
self.name, self.i18n_name = self.trAlgorithm('Merge vector layers')
self.group, self.i18n_group = self.trAlgorithm('Vector general tools')
self.addParameter(ParameterMultipleInput(self.LAYERS,
self.tr('Layers to merge'), datatype=ParameterMultipleInput.TYPE_VECTOR_ANY))
self.addOutput(OutputVector(self.OUTPUT, self.tr('Merged')))
def processAlgorithm(self, progress):
inLayers = self.getParameterValue(self.LAYERS)
paths = inLayers.split(';')
layers = []
fields = QgsFields()
totalFeatureCount = 0
for x in xrange(len(paths)):
layer = QgsVectorLayer(paths[x], unicode(x), 'ogr')
if (len(layers) > 0):
if (layer.wkbType() != layers[0].wkbType()):
raise GeoAlgorithmExecutionException(
self.tr('All layers must have same geometry type!'))
layers.append(layer)
totalFeatureCount += layer.featureCount()
for sindex, sfield in enumerate(layer.fields()):
found = None
for dfield in fields:
if (dfield.name().upper() == sfield.name().upper()):
found = dfield
if (dfield.type() != sfield.type()):
raise GeoAlgorithmExecutionException(
self.tr('{} field in layer {} has different '
'data type than in other layers.'))
if not found:
fields.append(sfield)
total = 100.0 / totalFeatureCount
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(
fields.toList(), layers[0].wkbType(),
layers[0].crs())
featureCount = 0
for layer in layers:
for feature in layer.getFeatures():
sattributes = feature.attributes()
dattributes = []
for dindex, dfield in enumerate(fields):
if (dfield.type() == QVariant.Int, QVariant.UInt, QVariant.LongLong, QVariant.ULongLong):
dattribute = 0
elif (dfield.type() == QVariant.Double):
dattribute = 0.0
else:
dattribute = ''
for sindex, sfield in enumerate(layer.fields()):
if (sfield.name().upper() == dfield.name().upper()):
if (sfield.type() != dfield.type()):
raise GeoAlgorithmExecutionException(
self.tr('Attribute type mismatch'))
dattribute = sattributes[sindex]
break
dattributes.append(dattribute)
feature.setAttributes(dattributes)
writer.addFeature(feature)
featureCount += 1
progress.setPercentage(int(featureCount * total))
del writer