Dispaly mil2525 symbology on a map using graphicsoverlay

Question

I am using SymbolStyle and graphicsoverlay in ArcGIS qt 100.5 to read and display symbols from a style file. The code for the function is as follows. m_mapView is my MapGraphicsView object. The application is successfully built. The application crashes when this function is called. The debug statements display true status for both tw1.isValid() and for tw1.isDone() . Can somebody guide me why this problem is occurring?? void offlinemap2d::addPointsFromStyleFile() { //create a new graphicsoverlay GraphicsOverlay* graphicsOverlay = new GraphicsOverlay(this); // create a list of points const QList pointsList { Point(72.852642647560347, 19.092812566811544, SpatialReference::wgs84()), Point(72.8708416959572303, 19.08444173689877, SpatialReference::wgs84()), Point(32.6697273884990937, 56.064250073402874, SpatialReference::wgs84()), Point(32.6395150461199726, 56.06127916736989, SpatialReference::wgs84()) }; QStringList params {"tank","friendly"}; // create the symbology for the points SymbolStyle* symbolstyle1 = new SymbolStyle("/home/developer/Desktop/stylx_files/mil2525d.stylx", this); TaskWatcher tw1 = symbolstyle1->fetchSymbol(param); qDebug()<fetchSymbolCompleted(tw1.taskId(),symbol1); foreach (const Point &buoyPoint, pointsList) { graphic = new Graphic(buoyPoint, this); graphic->setSymbol(symbol1); graphicsOverlay->graphics()->append(graphic); } //add overlay to the map m_mapView->graphicsOverlays()->append(graphicsOverlay); }

AbhijeetSatam · Answer

Your guess is right. Null is returned for the Symbol.

However, we are using mil2525d.stylx (http://arcgisfordefense.maps.arcgis.com/home/item.html?id=e34835bf5ec5430da7cf16bb8c0b075c) file and trying to fetch Symbol with keywords like 'tank' and 'friendly' as

QStringList params {"tank","friendly"};

Still we are not able to successfully display symbols on map.

Anonymous User · Answer

My first guess would be to check if the

Symbol*

provided from the connect argument list actually contains data, or if it is null. If it's null, it probably indicates that your data has not been loaded, or that the parameters provided are not being found inside the data.

(I don't think this is neccesary, but you can also try calling

symbolstyle1.load()

immediately after the symbolStyle has been initialised. It may help.)

AbhijeetSatam · Answer

Hi Elliot, I tried using your suggestion . The application is successfully built now and does not crash when run. However the points are not displayed on the map. The code I have used is as follows. The debug statement added is displayed in the console. void offlinemap2d::addPointsFromStyleFile() { //create a new graphicsoverlay GraphicsOverlay* graphicsOverlay = new GraphicsOverlay(this); // create a list of points const QList pointsList { Point(72.852642647560347, 19.092812566811544, SpatialReference::wgs84()), Point(72.8708416959572303, 19.08444173689877, SpatialReference::wgs84()), Point(32.6697273884990937, 56.064250073402874, SpatialReference::wgs84()), Point(32.6395150461199726, 56.06127916736989, SpatialReference::wgs84()) }; QStringList params {"tank","friendly"}; // create the symbology for the points SymbolStyle* symbolstyle1 = new SymbolStyle("/home/developer/Desktop/stylx_files/mil2525d.stylx", this); TaskWatcher tw1 = symbolstyle1->fetchSymbol(param); connect(symbolstyle1, &SymbolStyle::fetchSymbolCompleted, this, [graphicsOverlay, pointsList, this](QUuid taskId, Symbol* symbol) { qDebug()<<"inside connect"; foreach (const Point &buoyPoint, pointsList) { auto graphic = new Graphic(buoyPoint, this); graphic->setSymbol(symbol); graphicsOverlay->graphics()->append(graphic); } m_mapView->graphicsOverlays()->append(graphicsOverlay); }); }