topic Re: Can't setting SpatialReference and get Latitude/Longitude QML in Qt Maps SDK Questions

Can't setting SpatialReference and get Latitude/Longitude QML

KanjaSousuke — Wed, 28 Apr 2021 02:16:27 GMT

I use Esri.ArcGISRuntime 100.9 and Qt5.15.0.

I want to get Latitude and Longitude, but can't get.

My code is

ApplicationWindow { id: appWindow width: 800 height: 600 title: "MapTest2" property int count: 0 // add a mapView component MapView { id: mapView anchors.fill: parent // set focus to enable keyboard navigation focus: true // add a map to the mapview Map { // add the BasemapTopographic basemap to the map BasemapTopographic {} } MultipointBuilder{ id: clickPoint spatialReference: SpatialReference { wkid: 6668 } } onMouseClicked: { console.log(mouse.mapPoint.x) console.log(clickPoint.points.addPoint(screenToLocation(mouse.x,mouse.y))) console.log(clickPoint.points.point(count).x) count++ } } }

This code display the following statement in the console.

qml: 11170910.901105005
qml: -1
qrc:/qml/main.qml:50: TypeError: Cannot read property 'x' of null

I think this problem is [SpatialReference].

Because, when I did the following and got no errors or anything.

MultipointBuilder{ id: clickPoint spatialReference: mapView.spatialReference }

But, this code can't get Latitude/Longitude in wkid:6668

Is there any way we can solve this problem?

Re: Can't setting SpatialReference and get Latitude/Longitude QML

LucasDanzinger — Wed, 28 Apr 2021 13:59:55 GMT

I believe the issue might be that your points/coordinates coming from the mapview click event is coming in 3857 (web mercator), and then you are trying to add these points to a builder that is using 6668.

My suggestion is to use GeometryEngine.project to take the 3857-based points and project them into 6668 before you call addPoint on the builder. That way, you are adding the points to the builder in the correct spatial reference

https://developers.arcgis.com/qt/qml/api-reference/qml-esri-arcgisruntime-geometryengine.html#project-method

Re: Can't setting SpatialReference and get Latitude/Longitude QML

KanjaSousuke — Mon, 10 May 2021 00:12:03 GMT

Thanks!

I can get.