Source code for safe.gis.qgis_interface

# coding=utf-8
InaSAFE Disaster risk assessment tool developed by AusAid -
**QGIS plugin implementation.**

Contact : [email protected]

.. note:: 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.

.. note:: This source code was copied from the 'postgis viewer' application
     with original authors:
     Copyright (c) 2010 by Ivan Mincik, [email protected]
     Copyright (c) 2011 German Carrillo, [email protected]


__author__ = '[email protected]'
__revision__ = '$Format:%H$'
__date__ = '10/01/2011'
__copyright__ = (
    'Copyright (c) 2010 by Ivan Mincik, [email protected] and '
    'Copyright (c) 2011 German Carrillo, [email protected]'
    'Copyright (c) 2014 Tim Sutton, [email protected]'

import logging

from qgis.core import QgsMapLayerRegistry, QGis, QgsMapLayer, QgsProject
# pylint: disable=no-name-in-module
from qgis.gui import (
from PyQt4.QtCore import QObject, pyqtSlot, pyqtSignal
from safe.gis.qgis_legend_interface import QgisLegend
from qgis.gui import QgsLayerTreeMapCanvasBridge

LOGGER = logging.getLogger('InaSAFE')

# noinspection PyMethodMayBeStatic,PyPep8Naming
[docs]class QgisInterface(QObject): """Class to expose qgis objects and functions to plugins. This class is here for enabling us to run unit tests only, so most methods are simply stubs. """ currentLayerChanged = pyqtSignal(QgsMapCanvasLayer) layerSavedAs = pyqtSignal(QgsMapLayer, str) def __init__(self, canvas): """Constructor :param canvas: """ QObject.__init__(self) self.canvas = canvas self.legend = QgisLegend(canvas) self.message_bar = QgsMessageBar(None) # Set up slots so we can mimic the behaviour of QGIS when layers # are added. LOGGER.debug('Initialising canvas...') # noinspection PyArgumentList QgsMapLayerRegistry.instance().layersAdded.connect(self.addLayers) # noinspection PyArgumentList QgsMapLayerRegistry.instance().layerWasAdded.connect(self.addLayer) # noinspection PyArgumentList QgsMapLayerRegistry.instance().removeAll.connect(self.removeAllLayers) # For processing module self.destCrs = None # For keeping track of which layer is active in the legend. self.active_layer = None # In the next section of code, we are going to do some monkey patching # to make the QGIS processing framework think that this mock QGIS IFACE # instance is the actual one. It will also ensure that the processing # algorithms are nicely loaded and available for use. # Since QGIS > 2.0, the module is moved from QGisLayers to dataobjects # pylint: disable=F0401, E0611 if QGis.QGIS_VERSION_INT > 20001: # noinspection PyUnresolvedReferences from import dataobjects else: # noinspection PyUnresolvedReferences from processing.core import QGisLayers as dataobjects # noinspection PyUnresolvedReferences import processing # noinspection PyUnresolvedReferences from processing.core.Processing import Processing # pylint: enable=F0401, E0611 processing.classFactory(self) # We create our own getAlgorithm function below which will will monkey # patch in to the Processing class in QGIS in order to ensure that the # Processing.initialize() call is made before asking for an alg. @staticmethod def mock_getAlgorithm(name): """ Modified version of the original getAlgorithm function. :param name: Name of the algorithm to load. :type name: str :return: An algorithm concrete class. :rtype: QgsAlgorithm ? """ Processing.initialize() for provider in Processing.algs.values(): if name in provider: return provider[name] return None # Now we let the monkey loose! Processing.getAlgorithm = mock_getAlgorithm # We also need to make dataobjects think that this iface is 'the one' # Note. the placement here (after the getAlgorithm monkey patch above) # is significant, so don't move it! dataobjects.iface = self # set up a layer tree bridge so that new added layers appear in legend self.layer_tree_root = QgsProject.instance().layerTreeRoot() self.bridge = QgsLayerTreeMapCanvasBridge( self.layer_tree_root, self.canvas) self.bridge.setCanvasLayers() def __getattr__(self, *args, **kwargs): # It's for processing module def dummy(*a, **kwa): _ = a, kwa return QgisInterface(self.canvas) return dummy def __iter__(self): # It's for processing module return self
[docs] def next(self): # It's for processing module raise StopIteration
[docs] def layers(self): # It's for processing module # simulate iface.legendInterface().layers() return QgsMapLayerRegistry.instance().mapLayers().values()
[docs] def addLayers(self, layers): """Handle layers being added to the registry so they show up in canvas. :param layers: list<QgsMapLayer> list of map layers that were added .. note:: The QgsInterface api does not include this method, it is added here as a helper to facilitate testing. """ # LOGGER.debug('addLayers called on qgis_interface') # LOGGER.debug('Number of layers being added: %s' % len(layers)) # LOGGER.debug('Layer Count Before: %s' % len(self.canvas.layers())) current_layers = self.canvas.layers() final_layers = [] # We need to keep the record of the registered layers on our canvas! registered_layers = [] for layer in current_layers: final_layers.append(QgsMapCanvasLayer(layer)) registered_layers.append( for layer in layers: if not in registered_layers: final_layers.append(QgsMapCanvasLayer(layer)) self.canvas.setLayerSet(final_layers) # LOGGER.debug('Layer Count After: %s' % len(self.canvas.layers()))
[docs] def addLayer(self, layer): """Handle a layer being added to the registry so it shows up in canvas. :param layer: list<QgsMapLayer> list of map layers that were added .. note: The QgsInterface api does not include this method, it is added here as a helper to facilitate testing. .. note: The addLayer method was deprecated in QGIS 1.8 so you should not need this method much. """ pass
[docs] def removeAllLayers(self, ): """Remove layers from the canvas before they get deleted. .. note:: This is NOT part of the QGisInterface API but is needed to support QgsMapLayerRegistry.removeAllLayers(). """ self.canvas.setLayerSet([]) self.active_layer = None
[docs] def newProject(self): """Create new project.""" # noinspection PyArgumentList QgsMapLayerRegistry.instance().removeAllMapLayers() # ---------------- API Mock for QgsInterface follows -------------------
[docs] def zoomFull(self): """Zoom to the map full extent.""" pass
[docs] def zoomToPrevious(self): """Zoom to previous view extent.""" pass
[docs] def zoomToNext(self): """Zoom to next view extent.""" pass
[docs] def zoomToActiveLayer(self): """Zoom to extent of active layer.""" pass
[docs] def addVectorLayer(self, path, base_name, provider_key): """Add a vector layer. :param path: Path to layer. :type path: str :param base_name: Base name for layer. :type base_name: str :param provider_key: Provider key e.g. 'ogr' :type provider_key: str """ pass
[docs] def addRasterLayer(self, path, base_name): """Add a raster layer given a raster layer file name :param path: Path to layer. :type path: str :param base_name: Base name for layer. :type base_name: str """ pass
[docs] def setActiveLayer(self, layer): """Set the currently active layer in the legend. :param layer: Layer to make active. :type layer: QgsMapLayer, QgsVectorLayer, QgsRasterLayer """ self.active_layer = layer
[docs] def activeLayer(self): """Get pointer to the active layer (layer selected in the legend).""" if self.active_layer is not None: return self.active_layer else: return None
[docs] def addToolBarIcon(self, action): """Add an icon to the plugins toolbar. :param action: Action to add to the toolbar. :type action: QAction """ pass
[docs] def removeToolBarIcon(self, action): """Remove an action (icon) from the plugin toolbar. :param action: Action to add to the toolbar. :type action: QAction """ pass
[docs] def addToolBar(self, name): """Add toolbar with specified name. :param name: Name for the toolbar. :type name: str """ pass
[docs] def mapCanvas(self): """Return a pointer to the map canvas.""" return self.canvas
[docs] def mainWindow(self): """Return a pointer to the main window. In case of QGIS it returns an instance of QgisApp. """ pass
[docs] def addDockWidget(self, area, dock_widget): """Add a dock widget to the main window. :param area: Where in the ui the dock should be placed. :type area: :param dock_widget: A dock widget to add to the UI. :type dock_widget: QDockWidget """ pass
[docs] def legendInterface(self): """Get the legend. See also discussion at: Implementation added for version 3.2. """ return self.legend
[docs] def messageBar(self): """Get the message bar. .. versionadded:: 3.2 :returns: A QGIS message bar instance :rtype: QgsMessageBar """ return self.message_bar