本文整理汇总了Python中qgis.core.QgsRelation.id方法的典型用法代码示例。如果您正苦于以下问题：Python QgsRelation.id方法的具体用法？Python QgsRelation.id怎么用？Python QgsRelation.id使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类qgis.core.QgsRelation的用法示例。
在下文中一共展示了QgsRelation.id方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: import_in_qgis
# 需要导入模块: from qgis.core import QgsRelation [as 别名]
# 或者: from qgis.core.QgsRelation import id [as 别名]
def import_in_qgis(gmlas_uri, provider, schema = None):
"""Imports layers from a GMLAS file in QGIS with relations and editor widgets
@param gmlas_uri connection parameters
@param provider name of the QGIS provider that handles gmlas_uri parameters (postgresql or spatialite)
@param schema name of the PostgreSQL schema where tables and metadata tables are
"""
if schema is not None:
schema_s = schema + "."
else:
schema_s = ""
ogr.UseExceptions()
drv = ogr.GetDriverByName(provider)
ds = drv.Open(gmlas_uri)
if ds is None:
raise RuntimeError("Problem opening {}".format(gmlas_uri))
# get list of layers
sql = "select o.*, g.f_geometry_column, g.srid from {}_ogr_layers_metadata o left join geometry_columns g on g.f_table_name = o.layer_name".format(schema_s)
l = ds.ExecuteSQL(sql)
layers = {}
for f in l:
ln = f.GetField("layer_name")
if ln not in layers:
layers[ln] = {
'uid': f.GetField("layer_pkid_name"),
'category': f.GetField("layer_category"),
'xpath': f.GetField("layer_xpath"),
'parent_pkid': f.GetField("layer_parent_pkid_name"),
'srid': f.GetField("srid"),
'geometry_column': f.GetField("f_geometry_column"),
'1_n' : [], # 1:N relations
'layer_id': None,
'layer_name' : ln,
'layer': None,
'fields' : []}
else:
# additional geometry columns
g = f.GetField("f_geometry_column")
k = "{} ({})".format(ln, g)
layers[k] = dict(layers[ln])
layers[k]["geometry_column"] = g
# collect fields with xlink:href
href_fields = {}
for ln, layer in layers.items():
layer_name = layer["layer_name"]
for f in ds.ExecuteSQL("select field_name, field_xpath from {}_ogr_fields_metadata where layer_name='{}'".format(schema_s, layer_name)):
field_name, field_xpath = f.GetField("field_name"), f.GetField("field_xpath")
if field_xpath and field_xpath.endswith("@xlink:href"):
if ln not in href_fields:
href_fields[ln] = []
href_fields[ln].append(field_name)
# with unknown srid, don't ask for each layer, set to a default
settings = QgsSettings()
projection_behavior = settings.value("Projections/defaultBehavior")
projection_default = settings.value("Projections/layerDefaultCrs")
settings.setValue("Projections/defaultBehavior", "useGlobal")
settings.setValue("Projections/layerDefaultCrs", "EPSG:4326")
# add layers
crs = QgsCoordinateReferenceSystem("EPSG:4326")
for ln in sorted(layers.keys()):
lyr = layers[ln]
g_column = lyr["geometry_column"] or None
l = _qgis_layer(gmlas_uri, schema, lyr["layer_name"], g_column, provider, ln, lyr["xpath"], lyr["uid"])
if not l.isValid():
raise RuntimeError("Problem loading layer {} with {}".format(ln, l.source()))
if g_column is not None:
if lyr["srid"]:
crs = QgsCoordinateReferenceSystem("EPSG:{}".format(lyr["srid"]))
l.setCrs(crs)
QgsProject.instance().addMapLayer(l)
layers[ln]['layer_id'] = l.id()
layers[ln]['layer'] = l
# save fields which represent a xlink:href
if ln in href_fields:
l.setCustomProperty("href_fields", href_fields[ln])
# save gmlas_uri
l.setCustomProperty("ogr_uri", gmlas_uri)
l.setCustomProperty("ogr_schema", schema)
# change icon the layer has a custom viewer
xpath = no_ns(l.customProperty("xpath", ""))
for viewer_cls, _ in get_custom_viewers().values():
tag = no_prefix(viewer_cls.xml_tag())
if tag == xpath:
lg = CustomViewerLegend(viewer_cls.name(), viewer_cls.icon())
l.setLegend(lg)
# restore settings
settings.setValue("Projections/defaultBehavior", projection_behavior)
settings.setValue("Projections/layerDefaultCrs", projection_default)
# add 1:1 relations
relations_1_1 = []
sql = """
#.........这里部分代码省略.........