How to create widget in pyqt5 to show google map

Question

How do I get latitude and longitude from user and show this location on map in pyqt5 widget?

My OS is Windows, and I found out this link:

https://github.com/

Answer 1

QtWebkit is deprecated from Qt 5.6 and was replaced by Qt WebEngine, and the same goes for PyQt, which generates the error. On the other hand my library implements it using Qt Webkit and I have not had time to implement it for PyQt but today I have done it (it is not fully tested).

As an observation, Google Maps currently requires a API KEY that you can obtain by following this guide. Also the class provides to get the position given the place name but you also have to enable it using this other guide.

For you to do a quick test I will provide an API KEY but I will disable it at any time.

main.py

import json

from PyQt5 import QtCore, QtWidgets, QtWebEngineWidgets, QtWebChannel, QtNetwork

HTML = '''



    
    
    
    
    





'''

JS = '''
// main var
var map;
var markers = [];
var qtWidget;

// main init function
function initialize() {
    var myOptions = {
        center: {lat: -34.397, lng: 150.644},
        zoom: 8
    };

    map = new google.maps.Map(document.getElementById('map_canvas'),
        myOptions);

    new QWebChannel(qt.webChannelTransport, function (channel) {
        qtWidget = channel.objects.qGoogleMap;
    });

    google.maps.event.addListener(map, 'dragend', function () {
        var center = map.getCenter();
        qtWidget.mapIsMoved(center.lat(), center.lng());
    });
    google.maps.event.addListener(map, 'click', function (ev) {
        qtWidget.mapIsClicked(ev.latLng.lat(), ev.latLng.lng());
    });
    google.maps.event.addListener(map, 'rightclick', function (ev) {
        qtWidget.mapIsRightClicked(ev.latLng.lat(), ev.latLng.lng());
    });
    google.maps.event.addListener(map, 'dblclick', function (ev) {
        qtWidget.mapIsDoubleClicked(ev.latLng.lat(), ev.latLng.lng());
    });
}
// custom functions
function gmap_setCenter(lat, lng) {
    map.setCenter(new google.maps.LatLng(lat, lng));
}
function gmap_getCenter() {
    return [map.getCenter().lat(), map.getCenter().lng()];
}
function gmap_setZoom(zoom) {
    map.setZoom(zoom);
}
function gmap_addMarker(key, latitude, longitude, parameters) {

    if (key in markers) {
        gmap_deleteMarker(key);
    }
    var coords = new google.maps.LatLng(latitude, longitude);
    parameters['map'] = map
    parameters['position'] = coords;
    var marker = new google.maps.Marker(parameters);
    google.maps.event.addListener(marker, 'dragend', function () {
        qtWidget.markerIsMoved(key, marker.position.lat(), marker.position.lng())
    });
    google.maps.event.addListener(marker, 'click', function () {
        qtWidget.markerIsClicked(key, marker.position.lat(), marker.position.lng())
    });
    google.maps.event.addListener(marker, 'dblclick', function () {
        qtWidget.markerIsDoubleClicked(key, marker.position.lat(), marker.position.lng())
    });
    google.maps.event.addListener(marker, 'rightclick', function () {
        qtWidget.markerIsRightClicked(key, marker.position.lat(), marker.position.lng())
    });
    markers[key] = marker;
    return key;
}
function gmap_moveMarker(key, latitude, longitude) {
    var coords = new google.maps.LatLng(latitude, longitude);
    markers[key].setPosition(coords);
}
function gmap_deleteMarker(key) {
    markers[key].setMap(null);
    delete markers[key]
}
function gmap_changeMarker(key, extras) {
    if (!(key in markers)) {
        return
    }
    markers[key].setOptions(extras);
}
'''


class GeoCoder(QtNetwork.QNetworkAccessManager):
    class NotFoundError(Exception):
        pass

    def geocode(self, location, api_key):
        url = QtCore.QUrl("https://maps.googleapis.com/maps/api/geocode/xml")

        query = QtCore.QUrlQuery()
        query.addQueryItem("key", api_key)
        query.addQueryItem("address", location)
        url.setQuery(query)
        request = QtNetwork.QNetworkRequest(url)
        reply = self.get(request)
        loop = QtCore.QEventLoop()
        reply.finished.connect(loop.quit)
        loop.exec_()
        reply.deleteLater()
        self.deleteLater()
        return self._parseResult(reply)

    def _parseResult(self, reply):
        xml = reply.readAll()
        reader = QtCore.QXmlStreamReader(xml)
        while not reader.atEnd():
            reader.readNext()
            if reader.name() != "geometry": continue
            reader.readNextStartElement()
            if reader.name() != "location": continue
            reader.readNextStartElement()
            if reader.name() != "lat": continue
            latitude = float(reader.readElementText())
            reader.readNextStartElement()
            if reader.name() != "lng": continue
            longitude = float(reader.readElementText())
            return latitude, longitude
        raise GeoCoder.NotFoundError


class QGoogleMap(QtWebEngineWidgets.QWebEngineView):
    mapMoved = QtCore.pyqtSignal(float, float)
    mapClicked = QtCore.pyqtSignal(float, float)
    mapRightClicked = QtCore.pyqtSignal(float, float)
    mapDoubleClicked = QtCore.pyqtSignal(float, float)

    markerMoved = QtCore.pyqtSignal(str, float, float)
    markerClicked = QtCore.pyqtSignal(str, float, float)
    markerDoubleClicked = QtCore.pyqtSignal(str, float, float)
    markerRightClicked = QtCore.pyqtSignal(str, float, float)

    def __init__(self, api_key, parent=None):
        super(QGoogleMap, self).__init__(parent)
        self._api_key = api_key
        channel = QtWebChannel.QWebChannel(self)
        self.page().setWebChannel(channel)
        channel.registerObject("qGoogleMap", self)
        self.page().runJavaScript(JS)

        html = HTML.replace("API_KEY", "YOUR_API_KEY_HERE")
        self.setHtml(html)
        self.loadFinished.connect(self.on_loadFinished)
        self.initialized = False

        self._manager = QtNetwork.QNetworkAccessManager(self)

    @QtCore.pyqtSlot()
    def on_loadFinished(self):
        self.initialized = True

    def waitUntilReady(self):
        if not self.initialized:
            loop = QtCore.QEventLoop()
            self.loadFinished.connect(loop.quit)
            loop.exec_()

    def geocode(self, location):
        return GeoCoder(self).geocode(location, self._api_key)

    def centerAtAddress(self, location):
        try:
            latitude, longitude = self.geocode(location)
        except GeoCoder.NotFoundError:
            print("Not found {}".format(location))
            return None, None
        self.centerAt(latitude, longitude)
        return latitude, longitude

    def addMarkerAtAddress(self, location, **extra):
        if 'title' not in extra:
            extra['title'] = location
        try:
            latitude, longitude = self.geocode(location)
        except GeoCoder.NotFoundError:
            return None
        return self.addMarker(location, latitude, longitude, **extra)

    @QtCore.pyqtSlot(float, float)
    def mapIsMoved(self, lat, lng):
        self.mapMoved.emit(lat, lng)

    @QtCore.pyqtSlot(float, float)
    def mapIsClicked(self, lat, lng):
        self.mapClicked.emit(lat, lng)

    @QtCore.pyqtSlot(float, float)
    def mapIsRightClicked(self, lat, lng):
        self.mapRightClicked.emit(lat, lng)

    @QtCore.pyqtSlot(float, float)
    def mapIsDoubleClicked(self, lat, lng):
        self.mapDoubleClicked.emit(lat, lng)

    # markers
    @QtCore.pyqtSlot(str, float, float)
    def markerIsMoved(self, key, lat, lng):
        self.markerMoved.emit(key, lat, lng)

    @QtCore.pyqtSlot(str, float, float)
    def markerIsClicked(self, key, lat, lng):
        self.markerClicked.emit(key, lat, lng)

    @QtCore.pyqtSlot(str, float, float)
    def markerIsRightClicked(self, key, lat, lng):
        self.markerRightClicked.emit(key, lat, lng)

    @QtCore.pyqtSlot(str, float, float)
    def markerIsDoubleClicked(self, key, lat, lng):
        self.markerDoubleClicked.emit(key, lat, lng)

    def runScript(self, script, callback=None):
        if callback is None:
            self.page().runJavaScript(script)
        else:
            self.page().runJavaScript(script, callback)

    def centerAt(self, latitude, longitude):
        self.runScript("gmap_setCenter({},{})".format(latitude, longitude))

    def center(self):
        self._center = {}
        loop = QtCore.QEventLoop()

        def callback(*args):
            self._center = tuple(args[0])
            loop.quit()

        self.runScript("gmap_getCenter()", callback)
        loop.exec_()
        return self._center

    def setZoom(self, zoom):
        self.runScript("gmap_setZoom({})".format(zoom))

    def addMarker(self, key, latitude, longitude, **extra):
        return self.runScript(
            "gmap_addMarker("
            "key={!r}, "
            "latitude={}, "
            "longitude={}, "
            "{}"
            "); ".format(key, latitude, longitude, json.dumps(extra)))

    def moveMarker(self, key, latitude, longitude):
        return self.runScript(
            "gmap_moveMarker({!r}, {}, {});".format(key, latitude, longitude))

    def setMarkerOptions(self, keys, **extra):
        return self.runScript(
            "gmap_changeMarker("
            "key={!r}, "
            "{}"
            "); "
                .format(keys, json.dumps(extra)))

    def deleteMarker(self, key):
        return self.runScript(
            "gmap_deleteMarker("
            "key={!r} "
            "); ".format(key))


if __name__ == '__main__':
    import sys

    API_KEY = "YOUR_API_KEY_HERE"

    app = QtWidgets.QApplication(sys.argv)
    w = QGoogleMap(api_key=API_KEY)
    w.resize(640, 480)
    w.show()
    w.waitUntilReady()
    w.setZoom(14)
    lat, lng = w.centerAtAddress("Lima Peru")
    if lat is None and lng is None:
        lat, lng = -12.0463731, -77.042754
        w.centerAt(lat, lng)

    w.addMarker("MyDragableMark", lat, lng, **dict(
        icon="http://maps.gstatic.com/mapfiles/ridefinder-images/mm_20_red.png",
        draggable=True,
        title="Move me!"
    ))

    for place in ["Plaza Ramon Castilla", "Plaza San Martin", ]:
        w.addMarkerAtAddress(place, icon="http://maps.gstatic.com/mapfiles/ridefinder-images/mm_20_gray.png")

    w.mapMoved.connect(print)
    w.mapClicked.connect(print)
    w.mapRightClicked.connect(print)
    w.mapDoubleClicked.connect(print)
    sys.exit(app.exec_())

Soon update my repository with a tested version :-)