GPS tracker on Qt, map and track

I decided to practice Android programming on Qt. I chose GPS tracker as a theme.
The feature set of this tracker:

• take measurements from the GPS receiver;
• export the track to GPX ( GPS eXchange Format );
• display the track on the map;
• display time in transit, path length, average speed.

An example of working with a map in QtQuick will be given under the cut.

Plugin, PluginParameter and Map

The base types are in the Qt Location module. Qt Location can be used as backend:

• HERE ;
• Mapbox ;
• Open Street Map .

Work with a specific map provider is placed in plug-ins ( Plugin ), which are configured through parameters ( PluginParameter ).

Minimum example:

Plugin { id: plugin preferred: ["here", "osm"] required: Plugin.AnyMappingFeatures | Plugin.AnyGeocodingFeatures } Map { plugin: plugin width: ... height:... } 

At first I just used Open Street Map:

 Plugin { id: plugin name: "osm" } 

By default, the OSM card provider is MapQuest , which recently introduced a developer key. Then there was the question of moving to something else.

Open Street Map Plugin

The documentation lists the support:

• MapQuest;
• ThunderForest ;
• OpenStreetMap and community.

In order to use the last item, two conditions must be met:

Set the osm.mapping.host parameter:

 Plugin { id: mapPlugin name: "osm" PluginParameter { name: "osm.mapping.host"; value: "http://a.tile.openstreetmap.org/" } } 

Map indicate the use of the MapType.CustomMap map type .
For magic lovers:

 Map { id: map plugin: mapPlugin activeMapType: map.supportedMapTypes[7] } 

In order not to hope for the position of an element in the list supportedMapTypes , you can do this:

 Map { id: map plugin: mapPlugin zoomLevel: 16 width: item.width height:item.height property MapPolyline track } Timer { interval: 100; running: true; repeat: false onTriggered: { for(var i = 0; i < map.supportedMapTypes.length; ++i){ if(map.supportedMapTypes[i].style === MapType.CustomMap){ map.activeMapType = map.supportedMapTypes[i]; } } } } 

Track

To draw a track, I took a MapPolyline element, while creating it dynamically, to clear the map:

 function start() { mapItem.clearMapItems(); mapItem.track = Qt.createQmlObject('import QtLocation 5.6; MapPolyline {}', item); mapItem.track.line.width = 6; mapItem.track.line.color = 'red'; mapItem.addMapItem(mapItem.track); } function appendCoordinate(position){ mapItem.center = position; mapItem.track.addCoordinate(position) } Map { id: mapItem plugin: mapPlugin zoomLevel: 16 width: item.width height:item.height property MapPolyline track } 

At the start, I clear the map, create a track and put it on the map. When a new coordinate is added, the center of the map moves to the specified position and the track is extended.

Result:

Code available on github