QgsLayerRestorer::QgsLayerRestorer( const QList<QgsMapLayer *> &layers )
{
for ( QgsMapLayer *layer : layers )
{
QgsLayerSettings settings;
settings.name = layer->name();
QString style = layer->styleManager()->currentStyle();
settings.mNamedStyle = layer->styleManager()->currentStyle();
// set a custom property allowing to keep in memory if a SLD file has
// been loaded for rendering
layer->setCustomProperty( "readSLD", false );
QString errMsg;
QDomDocument sldDoc;
layer->exportSldStyle( sldDoc, errMsg );
( void )settings.mSldStyle.setContent( sldDoc.toString(), true ); // for namespace processing
switch ( layer->type() )
{
case QgsMapLayer::VectorLayer:
{
QgsVectorLayer *vLayer = qobject_cast<QgsVectorLayer *>( layer );
if ( vLayer )
{
settings.mOpacity = vLayer->opacity();
settings.mSelectedFeatureIds = vLayer->selectedFeatureIds();
settings.mFilter = vLayer->subsetString();
}
break;
}
case QgsMapLayer::LayerType::RasterLayer:
{
QgsRasterLayer *rLayer = qobject_cast<QgsRasterLayer *>( layer );
if ( rLayer )
{
settings.mOpacity = rLayer->renderer()->opacity();
}
break;
}
case QgsMapLayer::MeshLayer:
case QgsMapLayer::PluginLayer:
break;
}
mLayerSettings[layer] = settings;
}
}
QgsLayerRestorer::~QgsLayerRestorer()
{
for ( QgsMapLayer *layer : mLayerSettings.keys() )
{
QgsLayerSettings settings = mLayerSettings[layer];
layer->styleManager()->setCurrentStyle( settings.mNamedStyle );
layer->setName( mLayerSettings[layer].name );
// if a SLD file has been loaded for rendering, we restore the previous one
QString errMsg;
QDomElement root = settings.mSldStyle.firstChildElement( "StyledLayerDescriptor" );
QDomElement el = root.firstChildElement( "NamedLayer" );
if ( layer->customProperty( "readSLD", false ).toBool() )
{
layer->readSld( el, errMsg );
}
layer->removeCustomProperty( "readSLD" );
switch ( layer->type() )
{
case QgsMapLayer::LayerType::VectorLayer:
{
QgsVectorLayer *vLayer = qobject_cast<QgsVectorLayer *>( layer );
if ( vLayer )
{
vLayer->setOpacity( settings.mOpacity );
vLayer->selectByIds( settings.mSelectedFeatureIds );
vLayer->setSubsetString( settings.mFilter );
}
break;
}
case QgsMapLayer::LayerType::RasterLayer:
{
QgsRasterLayer *rLayer = qobject_cast<QgsRasterLayer *>( layer );
if ( rLayer )
{
rLayer->renderer()->setOpacity( settings.mOpacity );
}
break;
}
case QgsMapLayer::MeshLayer:
case QgsMapLayer::PluginLayer:
break;
}
}
}
