ZEB Toolbox

A QGIS-plugin as a toolbox for data of road monitoring and assessment in Germany (ZEB)

Goal of the project

The data of road monitoring and assessment in Germany are stored in a specific XML-schema, which cannot be read by different GI-systems. This plugin enables QGIS to extract the spatial information from the XML-files called Georohdaten and Rasterrohdaten and display them as temporary layers (directly in memory).

Change log

1.0.0 - Update for QGIS3
0.3.1 - remove unnecessary print-commands
0.3.0 store the last selected filename for the next file dialog, usage of message bar of QGIS
0.2.0 add new plugin icon
0.1.2 remove ZIP from plugin
0.1.1 remove error while installing plugin in QGIS
0.1.0 import of one single ZEB-file realised

Preliminary remarks

The plugin runs in QGIS 2 and uses PyQt4 and Python 3.
Just ZEB-files of the type Rohdaten[...]Geo can be displayed in QGIS.

Hints for developement

The plugin was created by the QGIS-plugin "plugin builder". All additional python files were created in the src-folder.

Import of ZEB-files

The python-files for the data import are stored in src/importer. The class ImportController creates two layers (one point-layer for storing the GPS-positions, one line-layer for storing the trajectory). The names of the layers are the file name. The attribute table of the point layer will be initialised in the following function of the ImportController-class:

def createAttributeTable(self, layer):
    layerData = layer.dataProvider()
    layerData.addAttributes([QgsField("lfdm", QVariant.Int),
    QgsField("x", QVariant.Double),
    QgsField("y", QVariant.Double),
    QgsField("z", QVariant.Double),
    QgsField("pictures", QVariant.String)])

Each feature represents one Datenstrom-element from the XML-file. The attribute lfdm is the identifier of each feature, the attributes x, y, z contains the coordinates of the feature. The attribute pictures stores all path of pictures within one Datenstrom-element.

The class ZebFileHandler contains the SAX-implementation for extracting the data from the XML-file. Member variables are defind to store data until the end tag is find. The functions startElement, characters and endElement extracting the data and store them in the member variables. At the end of each Datenstrom-element, the following function for creating a new point feature will be called:

def insertFeature(self, x, y, z, lfdm, pictures):
    #init the new feature
    feat = QgsFeature(self.pointLayer.pendingFields())

    #insert the attributes of the new feature
    feat.setAttribute("x", float(x))
    feat.setAttribute("y", float(y))
    feat.setAttribute("z", float(z))
    feat.setAttribute("lfdm", int(lfdm))
    feat.setAttribute("pictures", str(pictures))

    #create the geometry of the new feature
    feat.setGeometry(QgsGeometry.fromPoint(QgsPoint(float(x), float(y))))

    #add the feature to the layer
    self.pointLayer.addFeatures([feat])