Issues with maps

webzoid

I've done pretty extensive work using Qt mapping functionality. I started with the QML mapping examples and now having this transposed into a QWidgets application - using QML <> C++ function calls to update and retrieve information from the maps. I must admit, I much prefer the ESRI/OpenStreetMaps to GoogleMaps.

I find the QML implementation much faster and smoother than any QWebKit implementation I've come across plus there are signals available for when the map has loaded, etc.

Willing to share code if this would help but I have successfully used the googlemaps plugin even though it is 3rd party.

davidesalvetti

@webzoid said in Issues with maps:

I started with the QML mapping examples and now having this transposed into a QWidgets application - using QML <> C++ function calls to update and retrieve information from the maps.

It's exactly what I'm looking for!

I must admit, I much prefer the ESRI/OpenStreetMaps to GoogleMaps.

The problem is that I need Satellite view that ESRI doesn't support, am I right? The quality of the ESRI/World Imaginery is not good enough.

Willing to share code if this would help but I have successfully used the googlemaps plugin even though it is 3rd party.

It would help a lot! Maybe can you share also some code that uses googlemaps plugin? It works in debug, but when in release it doesn't show me nothing and says:

qrc:/qml/qml/MapTrack.qml:119: Error: Cannot assign [undefined] to QDeclarativeGeoMapType*

But if you see in my code here I use a GroupBox that should give me all the GeoMapTypes, but it gives me none. And this happens only in release, in debug everything works fine.

Thanks a lot for your time.

webzoid

@davidesalvetti

The ESRI map provider does indeed support satellite imagery - I am using this (and all other supported map types) in my end application. I appreciate what you're saying about the quality of the imagery though. Given that we are in the days of 4K, I think Google and the likes need to step up with their map imagery :)

It will take a little while but I'll put together some example code for you which shows the QML stuff working in a QWidgets application.

I think in your case in your QML, the following line is wrong:

onCurrentIndexChanged: myMap.activeMapType = myMap.supportedMapTypes[currentIndex]

Where is currentIndex obtained from? Have you tried replacing currentIndex with, say 1 just to test that the map type changes?

webzoid

Have you tried the qml map viewer example application - it'll show you the available map types for a given provider.

Also, have you checked out the ArcGIS Qt Runtime - https://developers.arcgis.com/qt/

This is something I'm looking to move over to as it seems to be a pretty comprehensive mapping solution

Konstantin Tokarev

@davidesalvetti said in Issues with maps:

But that's a known issue of QtWebKit, am I wrong?

It works fine here, both debug and release. Debug version may crash because of assertion failures on some sites. If program doesn't start, it might be because not all dlls were copied

davidesalvetti

@Konstantin-Tokarev what about this link? I downloaded these binaries https://github.com/annulen/webkit/releases/tag/qtwebkit-5.212.0-alpha2/qtwebkit-5.212.0_alpha2-qt59-mingw530-x86.zip , I extracted the files and I copied DDLs and others files in "C:\Qt\5.9.1\mingw53_32" in the corresponding folders.

The behaviour is that:

in debug mode is I put this line the program doesn't even start:

QWebView *view = new QWebView(this);

in release mode, the program starts but while charging the google map it crashes.

My app is minimal, I'm just showing this QWebView. All the DDLs are installed, I've checked. Maybe the binaries are wrong? I don't think so, I'm using qt 5.9.1 with mingw53_32 on Windows 10 x64, they should be correct. What am I missing?

Konstantin Tokarev

Right, it was fixed long time ago. Please use http://download.qt.io/snapshots/ci/qtwebkit/5.212/latest/qtwebkit/ and Qt 5.10

davidesalvetti

@webzoid said in Issues with maps:

The ESRI map provider does indeed support satellite imagery - I am using this (and all other supported map types) in my end application.

What mapType are you using? I have found ESRI/World Imaginary but the quality is a lot worst than google maps.
This is ESRI:

This is google maps:

There is a lot of difference, that's why I need to use google maps plugin. But I don' t understand one thing: did you manage to use googlemaps provider also in release mode? Can you try it?

It will take a little while but I'll put together some example code for you which shows the QML stuff working in a QWidgets application.

Thank you very much, I'll wait your examples :)

I think in your case in your QML, the following line is wrong:
onCurrentIndexChanged: myMap.activeMapType = myMap.supportedMapTypes[currentIndex]
Where is currentIndex obtained from? Have you tried replacing currentIndex with, say 1 just to test that the map type changes?

currentIndex is a property of groupbox, when in the groupbox you click and change the selected item it refreshes and it uses currentindex. I'm not an expert of QML but in debug mode it works and it works this way. In release mode it doesn't show possible maps type. Maybe do I have to put somewhere the api key?

Have you tried the qml map viewer example application - it'll show you the available map types for a given provider.

Yes I tried it, and sinceI added the third party library for google maps it shows me also googlemaps in the provider section. But same story, in debug it works, in release I can't even find it in provider.

davidesalvetti

@Konstantin-Tokarev Ok thanks, but which one should I download? From what I can see for MingGw si only available with windows 7. Does it work also with windows 10?

Konstantin Tokarev

@davidesalvetti Sure, "Windows 7" means only that it was built on Windows 7 machine (same as official Qt binaries)

davidesalvetti

For the answer to this question https://forum.qt.io/topic/90126/problem-with-qml-and-google-maps-plugin/3