QGIS/python/plugins/processing/algs/qgis/AddTableField.py
2017-07-07 09:27:35 +10:00

126 lines
5.3 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
AddTableField.py
---------------------
Date : August 2012
Copyright : (C) 2012 by Victor Olaya
Email : volayaf at gmail 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__ = 'Victor Olaya'
__date__ = 'August 2012'
__copyright__ = '(C) 2012, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
from qgis.PyQt.QtCore import QVariant
from qgis.core import (QgsField,
QgsFeature,
QgsFeatureSink,
QgsApplication,
QgsProcessingUtils,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterString,
QgsProcessingParameterNumber,
QgsProcessingParameterEnum,
QgsProcessingParameterFeatureSink,
QgsProcessingOutputVectorLayer)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
class AddTableField(QgisAlgorithm):
OUTPUT_LAYER = 'OUTPUT_LAYER'
INPUT_LAYER = 'INPUT_LAYER'
FIELD_NAME = 'FIELD_NAME'
FIELD_TYPE = 'FIELD_TYPE'
FIELD_LENGTH = 'FIELD_LENGTH'
FIELD_PRECISION = 'FIELD_PRECISION'
TYPES = [QVariant.Int, QVariant.Double, QVariant.String]
def group(self):
return self.tr('Vector table tools')
def __init__(self):
super().__init__()
self.type_names = [self.tr('Integer'),
self.tr('Float'),
self.tr('String')]
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT_LAYER,
self.tr('Input layer')))
self.addParameter(QgsProcessingParameterString(self.FIELD_NAME,
self.tr('Field name')))
self.addParameter(QgsProcessingParameterEnum(self.FIELD_TYPE,
self.tr('Field type'), self.type_names))
self.addParameter(QgsProcessingParameterNumber(self.FIELD_LENGTH,
self.tr('Field length'), QgsProcessingParameterNumber.Integer,
10, False, 1, 255))
self.addParameter(QgsProcessingParameterNumber(self.FIELD_PRECISION,
self.tr('Field precision'), QgsProcessingParameterNumber.Integer, 0, False, 0, 10))
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT_LAYER, self.tr('Added')))
self.addOutput(QgsProcessingOutputVectorLayer(self.OUTPUT_LAYER, self.tr('Added')))
self.source = None
self.fieldType = None
self.fieldLength = None
self.fieldName = None
self.fieldPrecision = None
self.sink = None
self.dest_id = None
def name(self):
return 'addfieldtoattributestable'
def displayName(self):
return self.tr('Add field to attributes table')
def prepareAlgorithm(self, parameters, context, feedback):
self.source = self.parameterAsSource(parameters, self.INPUT_LAYER, context)
self.fieldType = self.parameterAsEnum(parameters, self.FIELD_TYPE, context)
self.fieldName = self.parameterAsString(parameters, self.FIELD_NAME, context)
self.fieldLength = self.parameterAsInt(parameters, self.FIELD_LENGTH, context)
self.fieldPrecision = self.parameterAsInt(parameters, self.FIELD_PRECISION, context)
fields = self.source.fields()
fields.append(QgsField(self.fieldName, self.TYPES[self.fieldType], '',
self.fieldLength, self.fieldPrecision))
(self.sink, self.dest_id) = self.parameterAsSink(parameters, self.OUTPUT_LAYER, context,
fields, self.source.wkbType(), self.source.sourceCrs())
return True
def processAlgorithm(self, context, feedback):
features = self.source.getFeatures()
total = 100.0 / self.source.featureCount() if self.source.featureCount() else 0
for current, input_feature in enumerate(features):
if feedback.isCanceled():
break
output_feature = input_feature
attributes = input_feature.attributes()
attributes.append(None)
output_feature.setAttributes(attributes)
self.sink.addFeature(output_feature, QgsFeatureSink.FastInsert)
feedback.setProgress(int(current * total))
return True
def postProcessAlgorithm(self, context, feedback):
return {self.OUTPUT_LAYER: self.dest_id}