C++ (Cpp) QgsProject::addMapLayer示例

void TestQgsProject::testLayerFlags()
{
  QString dataDir( TEST_DATA_DIR ); //defined in CmakeLists.txt
  QString layerPath = dataDir + "/points.shp";
  QgsVectorLayer *layer1 = new QgsVectorLayer( layerPath, QStringLiteral( "points 1" ), QStringLiteral( "ogr" ) );
  QgsVectorLayer *layer2 = new QgsVectorLayer( layerPath, QStringLiteral( "points 2" ), QStringLiteral( "ogr" ) );

  QgsProject prj;
  prj.addMapLayer( layer1 );
  prj.addMapLayer( layer2 );

  layer2->setFlags( layer2->flags() & ~QgsMapLayer::Removable );

  QString layer2id = layer2->id();

  QTemporaryFile f;
  QVERIFY( f.open() );
  f.close();
  prj.setFileName( f.fileName() );
  prj.write();

  // test reading required layers back
  QgsProject prj2;
  prj2.setFileName( f.fileName() );
  QVERIFY( prj2.read() );
  QgsMapLayer *layer = prj.mapLayer( layer2id );
  QVERIFY( layer );
  QVERIFY( !layer->flags().testFlag( QgsMapLayer::Removable ) );
}