Python QgsRelation.referencedLayer方法代码示例

# 需要导入模块: from qgis.core import QgsRelation [as 别名]
# 或者: from qgis.core.QgsRelation import referencedLayer [as 别名]
    def testDuplicateFeature(self):
        """ test duplicating a feature """

        project = QgsProject().instance()

        # LAYERS
        # - add first layer (parent)
        layer1 = QgsVectorLayer("Point?field=fldtxt:string&field=pkid:integer",
                                "parentlayer", "memory")
        # > check first layer (parent)
        self.assertTrue(layer1.isValid())
        # -  set the value for the copy
        layer1.setDefaultValueDefinition(1, QgsDefaultValue("rand(1000,2000)"))
        # > check first layer (parent)
        self.assertTrue(layer1.isValid())
        # - add second layer (child)
        layer2 = QgsVectorLayer("Point?field=fldtxt:string&field=id:integer&field=foreign_key:integer",
                                "childlayer", "memory")
        # > check second layer (child)
        self.assertTrue(layer2.isValid())
        # - add layers
        project.addMapLayers([layer1, layer2])

        # FEATURES
        # - add 2 features on layer1 (parent)
        l1f1orig = QgsFeature()
        l1f1orig.setFields(layer1.fields())
        l1f1orig.setAttributes(["F_l1f1", 100])
        l1f2orig = QgsFeature()
        l1f2orig.setFields(layer1.fields())
        l1f2orig.setAttributes(["F_l1f2", 101])
        # > check by adding features
        self.assertTrue(layer1.dataProvider().addFeatures([l1f1orig, l1f2orig]))
        # add 4 features on layer2 (child)
        l2f1orig = QgsFeature()
        l2f1orig.setFields(layer2.fields())
        l2f1orig.setAttributes(["F_l2f1", 201, 100])
        l2f2orig = QgsFeature()
        l2f2orig.setFields(layer2.fields())
        l2f2orig.setAttributes(["F_l2f2", 202, 100])
        l2f3orig = QgsFeature()
        l2f3orig.setFields(layer2.fields())
        l2f3orig.setAttributes(["F_l2f3", 203, 100])
        l2f4orig = QgsFeature()
        l2f4orig.setFields(layer2.fields())
        l2f4orig.setAttributes(["F_l2f4", 204, 101])
        # > check by adding features
        self.assertTrue(layer2.dataProvider().addFeatures([l2f1orig, l2f2orig, l2f3orig, l2f4orig]))

        # RELATION
        # - create the relationmanager
        relMgr = project.relationManager()
        # - create the relation
        rel = QgsRelation()
        rel.setId('rel1')
        rel.setName('childrel')
        rel.setReferencingLayer(layer2.id())
        rel.setReferencedLayer(layer1.id())
        rel.addFieldPair('foreign_key', 'pkid')
        rel.setStrength(QgsRelation.Composition)
        # > check relation
        self.assertTrue(rel.isValid())
        # - add relation
        relMgr.addRelation(rel)
        # > check if referencedLayer is layer1
        self.assertEqual(rel.referencedLayer(), layer1)
        # > check if referencingLayer is layer2
        self.assertEqual(rel.referencingLayer(), layer2)
        # > check if the layers are correct in relation when loading from relationManager
        relations = project.relationManager().relations()
        relation = relations[list(relations.keys())[0]]
        # > check if referencedLayer is layer1
        self.assertEqual(relation.referencedLayer(), layer1)
        # > check if referencingLayer is layer2
        self.assertEqual(relation.referencingLayer(), layer2)
        # > check the relatedfeatures

        '''
        # testoutput 1
        print( "\nAll Features and relations")
        featit=layer1.getFeatures()
        f=QgsFeature()
        while featit.nextFeature(f):
            print( f.attributes())
            childFeature = QgsFeature()
            relfeatit=rel.getRelatedFeatures(f)
            while relfeatit.nextFeature(childFeature):
                 print( childFeature.attributes() )
        print( "\n--------------------------")

        print( "\nFeatures on layer1")
        for f in layer1.getFeatures():
            print( f.attributes() )

        print( "\nFeatures on layer2")
        for f in layer2.getFeatures():
            print( f.attributes() )
        '''

        # DUPLICATION
#.........这里部分代码省略.........

# 需要导入模块: from qgis.core import QgsRelation [as 别名]
# 或者: from qgis.core.QgsRelation import referencedLayer [as 别名]

#.........这里部分代码省略.........

    def deleteWrapper(self):
        if self.relationWidgetWrapper is not None:
            self.relationWidgetWrapper.valueChanged.disconnect(self.foreignKeyChanged)
            self.relationWidgetWrapper.setValue(None)
            del self.relationWidgetWrapper
            self.relationWidgetWrapper = None

    def foreignKeyChanged(self, newKey):
        if not self.relation.isValid() or not self.relation.referencingLayer().isEditable() or not self.referencingFeature.isValid():
            self.drawLink()
            return
        if not self.relation.referencingLayer().editBuffer().changeAttributeValue(self.referencingFeature.id(), self.referencingFieldIndex(), newKey):
            self.iface.messageBar().pushMessage("Link It", "Cannot change attribute value.", QgsMessageBar.CRITICAL)
        self.drawLink()

    def relationEditableChanged(self):
        if self.relationWidgetWrapper is not None:
            self.relationWidgetWrapper.setEnabled(self.relation.isValid() and self.relation.referencingLayer().isEditable())

    def layerValueChangedOutside(self, fid, fieldIdx, value):
        if not self.relation.isValid() or not self.referencingFeature.isValid() or self.relationWidgetWrapper is None:
            return
        # not the correct feature
        if fid != self.referencingFeature.id():
            return
        # not the correct field
        if fieldIdx != self.referencingFieldIndex():
            return
        # widget already has this value
        if value == self.relationWidgetWrapper.value():
            return
        self.relationWidgetWrapper.valueChanged.disconnect(self.foreignKeyChanged)
        self.relationWidgetWrapper.setValue(value)
        self.relationWidgetWrapper.valueChanged.connect(self.foreignKeyChanged)

    def referencingFieldIndex(self):
        if not self.relation.isValid():
            return -1
        fieldName = self.relation.fieldPairs().keys()[0]
        fieldIdx = self.relation.referencingLayer().fieldNameIndex(fieldName)
        return fieldIdx

    @pyqtSlot(bool, name="on_drawButton_toggled")
    def drawLink(self):
        self.settings.setValue("drawEnabled", self.drawButton.isChecked())
        self.linkRubber.reset()
        if not self.drawButton.isChecked() or not self.referencingFeature.isValid() or not self.relation.isValid():
            return

        referencedFeature = self.relationReferenceWidget.referencedFeature()
        if not referencedFeature.isValid():
            return

        p1 = self.centroid(self.relation.referencedLayer(), referencedFeature)
        p2 = self.centroid(self.relation.referencingLayer(), self.referencingFeature)
        geom = arc(p1, p2)

        self.linkRubber.setToGeometry(geom, None)
        self.linkRubber.setWidth(self.settings.value("rubberWidth"))
        self.linkRubber.setColor(self.settings.value("rubberColor"))
        self.linkRubber.setLineStyle(Qt.DashLine)

    def centroid(self, layer, feature):
        geom = feature.geometry()
        if geom.type() == QGis.Line:
            geom = geom.interpolate(geom.length()/2)
        else:
            geom = geom.centroid()
        return self.iface.mapCanvas().mapSettings().layerToMapCoordinates(layer, geom.asPoint())

    @pyqtSlot(name="on_highlightReferencingFeatureButton_clicked")
    def highlightReferencingFeature(self):
        self.deleteHighlight()
        if not self.relation.isValid() or not self.referencingFeature.isValid():
            return
        
        self.featureHighlight = QgsHighlight(self.iface.mapCanvas(), self.referencingFeature.geometry(), self.relation.referencingLayer())
        settings = QSettings()
        color = QColor( settings.value("/Map/highlight/color", QGis.DEFAULT_HIGHLIGHT_COLOR.name()))
        alpha = int(settings.value("/Map/highlight/colorAlpha", QGis.DEFAULT_HIGHLIGHT_COLOR.alpha()))
        bbuffer = float(settings.value("/Map/highlight/buffer", QGis.DEFAULT_HIGHLIGHT_BUFFER_MM))
        minWidth = float(settings.value("/Map/highlight/minWidth", QGis.DEFAULT_HIGHLIGHT_MIN_WIDTH_MM))
        
        self.featureHighlight.setColor(color)
        color.setAlpha(alpha)
        self.featureHighlight.setFillColor(color)
        self.featureHighlight.setBuffer(bbuffer)
        self.featureHighlight.setMinWidth(minWidth)
        self.featureHighlight.show()

        timer = QTimer(self)
        timer.setSingleShot(True)
        timer.timeout.connect(self.deleteHighlight)
        timer.start(3000)

    def deleteHighlight(self):
        if self.featureHighlight:
            del self.featureHighlight
        self.featureHighlight = None