1. 标记    GeoDataPlacemark *place = new GeoDataPlacemark( "Bucharest" );    place->setCoordinate( 25.97, 44.43, 0.0, GeoDataCoordinates::Degree );    place->setPopulation( 1877155 );    place->setCountryCode ( "Romania" );      GeoDataDocument *document = new GeoDataDocument;    document->append( place );     // Add the document to MarbleWidget's tree model    mapWidget->model()->treeModel()->addDocument( document );2. 初始位置    GeoDataCoordinates home(112, 30.0, 10.0, GeoDataCoordinates::Degree);    mapWidget->centerOn(home);3.鼠标当前位置        // Connect the map widget to the position label.    QObject::connect(mapWidget, SIGNAL(mouseMoveGeoPosition(QString)),        positionLabel, SLOT(setText(QString))); 4.设置投影 　　　mapWidget->setProjection( Mercator ); 5.获取设置控件 　　foreach ( AbstractFloatItem * floatItem, mapWidget->floatItems() )

if ( floatItem && floatItem->nameId() == "compass" ) { // Put the compass onto the left hand side floatItem->setPosition( QPoint( 10, 10 ) ); // Make the content size of the compass smaller floatItem->setContentSize( QSize( 50, 50 ) ); }

 6.绘制标记

　　void MyMarbleWidget::customPaint(GeoPainter* painter)

　　{

　　　　GeoDataCoordinates home(8.4, 49.0, 0.0, GeoDataCoordinates::Degree);

　　　　painter->setPen(Qt::green);

　　　　painter->drawEllipse(home, 17, 17);

　　　　painter->setPen(Qt::red);

　　　　painter->drawText(home, "Hello Marble!");

　　}