# -*- coding: utf-8 -*- """@package OsmLoadDlg This module provides all structures and methods neccessary for OSM data loading. Loading is done from XML file. After XML file selection and confirming the dialog three vector layers are created in Quantum GIS. Layer for points, one for lines and one for polygons. All these layers are created with OSM data provider. Data provider is the one, who parses an input XML file. OSM data loading can be canceled, in such case system returns to the same state as the one before loading. """ from ui_OsmLoadDlg import Ui_OsmLoadDlg from PyQt4.QtCore import * from PyQt4.QtGui import * from PyQt4 import * from sip import unwrapinstance from qgis.core import QgsVectorLayer, QgsMapLayerRegistry, QgsRectangle from sip import * class OsmLoadDlg(QDialog, Ui_OsmLoadDlg): """This class provides all structures and methods neccessary for OSM data loading. Loading is done from XML file. After XML file selection and confirming the dialog three vector layers are created in Quantum GIS. Layer for points, one for lines and one for polygons. All these layers are created with OSM data provider. Data provider is the one, who parses an input XML file. OSM data loading can be canceled, in such case system returns to the same state as the one before loading. """ def __init__(self, plugin): """The constructor. @param plugin is pointer to instance of OSM Plugin """ QDialog.__init__(self, None) self.setupUi(self) self.canvas=plugin.canvas self.dbm=plugin.dbm self.progress = None # we must connect action "click on browse button" with method for showing open file dialog QObject.connect(self.browseOSMButton,SIGNAL("clicked()"),self.showOpenFileDialog) QObject.connect(self.buttonBox,SIGNAL("accepted()"), self.onOK) for tag in ['name','place','highway','landuse','waterway','railway','amenity','tourism','learning']: item = QListWidgetItem(tag, self.lstTags) item.setFlags( Qt.ItemIsSelectable | Qt.ItemIsUserCheckable | Qt.ItemIsEnabled) item.setCheckState(Qt.Checked if tag == 'name' else Qt.Unchecked) # gui initialization self.initGui() def initGui(self): """Initializes GUI of OSM Load dialog. """ # load default values to combobox determining style for custom renderer self.styles=["Small scale","Medium scale","Large scale"] directory=QFileInfo(__file__).canonicalPath() self.styleFiles=[directory+"/styles/small_scale.style", directory+"/styles/medium_scale.style", directory+"/styles/big_scale.style"] self.styleCombo.addItems(self.styles) if not self.dbm.currentKey: self.chkReplaceData.setEnabled(False) def showOpenFileDialog(self): """Function opens dialog for selecting XML file. Only files with extension .osm can be selected. Default directory for file selection is remembered/reload. """ settings=QSettings() lastDir=settings.value("/OSM_Plugin/lastDir", QVariant(QString())).toString() # display file open dialog and get absolute path to selected file fileSelected=QFileDialog.getOpenFileName(self,"Choose an Open Street Map file",lastDir,"OSM Files (*.osm)"); # insert OSM file path into line edit control if not fileSelected.isNull(): self.OSMFileEdit.setText(fileSelected) # save directory fi=QFileInfo(fileSelected) settings.setValue("/OSM_Plugin/lastDir", QVariant(fi.path()) ) def onOK(self): """Function is called after clicking on OK button of OSM Load dialog. It performs all actions neccessary for OSM data loading. It creates three QGIS vector layers for loaded data (point,line,polygon layer). """ self.buttonBox.setEnabled(False) # after closing a dialog, we want to add map layers using osm provider self.fname = self.OSMFileEdit.text() if self.fname=='': QMessageBox.information(self, "OSM Load", QString("Please enter path to OSM data file.")) self.buttonBox.setEnabled(True) return osmfile = QFileInfo(self.fname) observer = "&observer="+str(unwrapinstance(self)) basename = osmfile.baseName() if not osmfile.exists(): QMessageBox.information(self, "OSM Load", QString("Path to OSM file is invalid: %1.").arg(self.fname)) return fLoaded=self.filesLoaded() replacing=self.chkReplaceData.isChecked() newDB=self.fname.toAscii().data()+".db" curDB=self.dbm.currentKey if basename in fLoaded and newDB<>curDB: QMessageBox.information(self, "Error", QString("Layers of OSM file \"%1\" are loaded already.").arg(self.fname)) return if replacing: # remove layers of current data first QgsMapLayerRegistry.instance().removeMapLayer(self.canvas.currentLayer().getLayerID(),True) if self.chkCustomRenderer.isChecked(): styleFile=self.styleFiles[self.styleCombo.currentIndex()] style="&style="+styleFile else: style="" # some specific tags? tag = "" for row in xrange(self.lstTags.count()): item = self.lstTags.item(row) if item.checkState() == Qt.Checked: if len(tag) > 0: tag += "+" tag += item.text() if len(tag) > 0: tag = "&tag=" + tag # freeze map canvas until all vector layers are created self.canvas.freeze(True) self.loadingCanceled=False self.setProperty("osm_stop_parsing",QVariant(0)) # add polygon layer polygonLayer = QgsVectorLayer(self.fname+"?type=polygon"+observer + tag + style, basename+" polygons", "osm") if self.loadingCanceled: polygonLayer=None return if not polygonLayer.isValid(): QMessageBox.information(self,"Error",QString("Failed to load polygon layer.")) return if self.chkCustomRenderer.isChecked(): self.setCustomRenderer(polygonLayer) QgsMapLayerRegistry.instance().addMapLayer(polygonLayer) # add line layer lineLayer = QgsVectorLayer(self.fname+"?type=line"+observer + tag + style, basename+" lines", "osm") if self.loadingCanceled: lineLayer=None return if not lineLayer.isValid(): QMessageBox.information(self,"Error",QString("Failed to load line layer.")) return if self.chkCustomRenderer.isChecked(): self.setCustomRenderer(lineLayer) QgsMapLayerRegistry.instance().addMapLayer(lineLayer) # add point layer pointLayer = QgsVectorLayer(self.fname+"?type=point"+observer + tag + style, basename+" points", "osm") if self.loadingCanceled: pointLayer=None return if not pointLayer.isValid(): QMessageBox.information(self,"Error",QString("Failed to load point layer.")) return if self.chkCustomRenderer.isChecked(): self.setCustomRenderer(pointLayer) QgsMapLayerRegistry.instance().addMapLayer(pointLayer) # remember layers self.polygonLayer=polygonLayer self.lineLayer=lineLayer self.pointLayer=pointLayer self.canvas.freeze(False) rect=self.canvas.extent() if self.chkCustomRenderer.isChecked(): midX=rect.xMinimum()+(rect.xMaximum()-rect.xMinimum())/2 midY=rect.yMinimum()+(rect.yMaximum()-rect.yMinimum())/2 rX=rect.xMaximum()-midX rY=rect.yMaximum()-midY st=self.styles[self.styleCombo.currentIndex()] if st=="Small scale": rect=QgsRectangle(midX-rX/5,midY-rY/5,midX+rX/5,midY+rY/5) elif st=="Medium scale": rect=QgsRectangle(midX-rX/2,midY-rY/2,midX+rX/2,midY+rY/2) self.canvas.setExtent(rect) self.canvas.refresh() self.accept() def setCustomRenderer(self, layer): """Function provides a way how to set custom renderer. For more check changeAttributeValues() implementation of OSM provider. @param layer point to QGIS vector layer """ import sip layerAddr = sip.unwrapinstance(layer) layer.dataProvider().changeAttributeValues( { 0x12345678 : { 0 : QVariant(layerAddr) } } ) def filesLoaded(self): """Function returns list of keys of all currently loaded vector layers. Note that names are not absolute and not unique. @return list of keys of all currently loaded vector layers """ mapLayers=QgsMapLayerRegistry.instance().mapLayers() fLoaded=[] for ix in mapLayers.keys(): fileName=QString(ix) pos=ix.lastIndexOf("_") fileName=fileName.left(pos) if fileName not in fLoaded: fLoaded.append(fileName) return fLoaded def cancelLoading(self): """Function is called when progress dialog is canceled It's purpose is to tell OSM provider to stop XML file parsing. """ self.setProperty("osm_stop_parsing",QVariant(1)) self.loadingCanceled=True def event(self, e): """Function is used for OSM provider <-> OSM Plugin communication. """ if e.type() == QEvent.DynamicPropertyChange: if e.propertyName() == "osm_status": # we're starting new part if not self.progress: self.progress = QProgressDialog(self) self.progress.setAutoClose(False) self.progress.setModal(True) QObject.connect(self.progress,SIGNAL("canceled()"),self.cancelLoading) self.progress.show() status = self.property("osm_status").toString() self.progress.setLabelText(status) self.progress.setValue(0) if e.propertyName() == "osm_max": if not self.loadingCanceled: # we've got new max. value osm_max = self.property("osm_max").toInt()[0] self.progress.setMaximum(osm_max) elif e.propertyName() == "osm_value": if not self.loadingCanceled: # update in progressbar osm_val = self.property("osm_value").toInt()[0] self.progress.setValue(osm_val) elif e.propertyName() == "osm_done": if not self.loadingCanceled: # we're done QObject.disconnect(self.progress,SIGNAL("canceled()"),self.cancelLoading) self.progress.close() self.progress = None elif e.propertyName() == "osm_failure": if not self.loadingCanceled: self.loadingCanceled=True QObject.disconnect(self.progress,SIGNAL("canceled()"),self.cancelLoading) self.progress.close() self.progress = None QMessageBox.information(self,"Error",QString("Failed to load layers: %1") .arg(self.property("osm_failure").toString())) self.buttonBox.setEnabled(True) qApp.processEvents() return QDialog.event(self,e)