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QGeoRoutingManager Class ReferenceThe QGeoRoutingManager class provides support for geographic routing operations. More... #include <QGeoRoutingManager> Inherits QObject. Public Functions
Signals
Additional Inherited Members
Detailed DescriptionThe QGeoRoutingManager class provides support for geographic routing operations. The calculateRoute() and updateRoute() methods function QGeoRouteReply objects, which manage these operations and report on the result of the operations and any errors which may have occurred. The calculateRoute() function is used to find a route (or routes) that follows a set of waypoints and matches various other criteria. The QGeoRouteRequest class is used to specify this information. If supportsRouteUpdates() returns true then the QGeoRoutingManager supports updating route information based on position updates. This will cause the travel time and distance estimates to be updated, and any QGeoRouteSegments already traversed to be removed from the route. The updates can be triggered with the updateRoute() function, which makes use of the QGeoPositionInfo instances emitted as position updates by QGeoPositionInfoSource. Instances of QGeoRoutingManager can be accessed with QGeoServiceProvider::routingManager(). A small example of the usage of QGeoRoutingManager and QGeoRouteRequests follows: class MyRouteHandler : public QObject
{
Q_OBJECT
public:
MyRouteHandler(QGeoRoutingManager *routingManager,
const QGeoCoordinate &origin,
const QGeoCoordinate &destination) {
QGeoRouteRequest request(origin, destination);
// The request defaults to the fastest route by car, which is
// equivalent to:
// request.setTravelMode(QGeoRouteRequest::CarTravel);
// request.setRouteOptimization(QGeoRouteRequest::FastestRoute);
request.setAvoidFeatureTypes(QGeoRouteRequest::AvoidTolls);
request.setAvoidFeatureTypes(QGeoRouteRequest::AvoidMotorPoolLanes);
QGeoRouteRequest::AvoidFeaturesTypes avoidableFeatures = routingManager->supportedAvoidFeatureTypes();
if (!(avoidableFeatures & request.avoidFeatureTypes())) {
// ... inform the user that the routing manager does not
// provide support for avoiding tolls and/or motor pool lanes ...
return;
}
QGeoRouteReply *reply = routingManager->calculateRoute(request);
if (reply->isFinished()) {
if (reply->error() == QGeoRouteReply::NoError) {
routeCalculated(reply);
} else {
routeError(reply, reply->error(), reply->errorString());
}
return;
}
connect(routingManager,
SIGNAL(finished(QGeoRouteReply*)),
this,
SLOT(routeCalculated(QGeoRouteReply*)));
connect(routingManager,
SIGNAL(error(QGeoRouteReply*,QGeoRouteReply::Error,QString)),
this,
SLOT(routeError(QGeoRouteReply*,QGeoRouteReply::Error,QString)));
}
private slots:
void routeCalculated(QGeoRouteReply *reply)
{
// A route request can ask for several alternative routes ...
if (reply->routes().size() != 0) {
// ... but by default it will only get a single route
QGeoRoute route = reply->routes().at(0);
//... now we have to make use of the route ...
}
reply->deleteLater();
}
void routeError(QGeoRouteReply *reply, QGeoRouteReply:Error error, const QString &errorString)
{
// ... inform the user that an error has occurred ...
reply->deleteLater();
}
};
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