diff --git a/doc/api_break.dox b/doc/api_break.dox
index 3e0a804fca6..494461c0fa1 100644
--- a/doc/api_break.dox
+++ b/doc/api_break.dox
@@ -1467,6 +1467,8 @@ in code which previously passed a null pointer to QgsVectorLayerImport.</li>
 
 <ul>
 <li>Has been renamed to QgsMapThemeCollection</li>
+<li>The nested class PresetRecord has been renamed to MapThemeRecord</li>
+<li>Various member functions have been renamed from *preset* to *mapTheme*</li>
 </ul>
 
 \subsection qgis_api_break_3_0_QgsVectorFileWriter QgsVectorFileWriter
diff --git a/python/core/qgsmapthemecollection.sip b/python/core/qgsmapthemecollection.sip
index e0377bb3197..490731d444a 100644
--- a/python/core/qgsmapthemecollection.sip
+++ b/python/core/qgsmapthemecollection.sip
@@ -1,9 +1,9 @@
 /**
   \class QgsMapThemeCollection
   \ingroup core
-  \brief Container class that allows storage of visibility presets consisting of visible
+  \brief Container class that allows storage of map themes consisting of visible
    map layers and layer styles.
-  \note added in QGIS 2.12
+  \note Added in QGIS 2.12, renamed for QGIS 3.0
 */
 
 class QgsMapThemeCollection : QObject
@@ -13,119 +13,134 @@ class QgsMapThemeCollection : QObject
 %End
   public:
 
-    /** Individual preset record of visible layers and styles.
+    /** \ingroup core
+     * Individual map theme record of visible layers and styles.
      */
-    class PresetRecord
+    class MapThemeRecord
     {
       public:
 
-        bool operator==( const QgsMapThemeCollection::PresetRecord& other ) const;
-        bool operator!=( const QgsMapThemeCollection::PresetRecord& other ) const;
+        bool operator==( const QgsMapThemeCollection::MapThemeRecord& other ) const;
+        bool operator!=( const QgsMapThemeCollection::MapThemeRecord& other ) const;
 
-        //! Ordered list of layers that are visible
-        QStringList mVisibleLayerIDs;
-        /** For layers that have checkable legend symbols and not all symbols are checked - list which ones are
+        /**
+         * Ordered list of visible layers
+         */
+        QStringList visibleLayerIds() const;
+
+        /**
+         * Ordered list of visible layers
+         */
+        void setVisibleLayerIds( const QStringList& visibleLayerIds );
+
+        /**
+         * Lists which legend symbols are checked for layers which support this and where
+         * not all symbols are checked.
          * @note not available in Python bindings
          */
-        //QMap<QString, QSet<QString> > mPerLayerCheckedLegendSymbols;
-        //! For layers that use multiple styles - which one is currently selected
-        QMap<QString, QString> mPerLayerCurrentStyle;
+//        QMap<QString, QSet<QString> > perLayerCheckedLegendSymbols() const;
+
+        /**
+         * Lists which legend symbols are checked for layers which support this and where
+         * not all symbols are checked.
+         * @note not available in Python bindings
+         */
+//        void setPerLayerCheckedLegendSymbols(const QMap<QString, QSet<QString> >& perLayerCheckedLegendSymbols);
+
+        /**
+         * The currently used style name for layers with multiple styles.
+         * The map has layer ids as keys and style names as values.
+         */
+        QMap<QString, QString> perLayerCurrentStyle() const;
+
+        /**
+         * The currently used style name for layers with multiple styles.
+         * The map has layer ids as keys and style names as values.
+         */
+        void setPerLayerCurrentStyle(const QMap<QString, QString>& perLayerCurrentStyle);
+
     };
 
     QgsMapThemeCollection();
 
-    /** Returns whether a preset with a matching name exists.
-     * @param name name of preset to check
-     * @returns true if preset exists
+    /**
+     * Returns whether a map theme with a matching name exists.
      */
-    bool hasPreset( const QString& name ) const;
+    bool hasMapTheme( const QString& name ) const;
 
-    /** Inserts a new preset to the collection.
-     * @param name name of preset
-     * @param state preset record
+    /**
+     * Inserts a new map theme to the collection.
      * @see update()
      */
-    void insert( const QString& name, const PresetRecord& state );
+    void insert( const QString& name, const MapThemeRecord& state );
 
-    /** Updates a preset within the collection.
-     * @param name name of preset to update
-     * @param state preset record to replace existing preset
+    /**
+     * Updates a map theme within the collection.
+     * @param name name of map theme to update
+     * @param state map theme record to replace existing map theme
      * @see insert()
      */
-    void update( const QString& name, const PresetRecord& state );
+    void update( const QString& name, const MapThemeRecord& state );
 
-    /** Remove existing preset from collection.
-     * @param name preset name
+    /**
+     * Remove an existing map theme from collection.
      */
-    void removePreset( const QString& name );
+    void removeMapTheme( const QString& name );
 
-    //! Remove all presets from the collection.
+    //! Remove all map themes from the collection.
     void clear();
 
-    //! Returns a list of existing preset names.
-    QStringList presets() const;
+    //! Returns a list of existing map theme names.
+    QStringList mapThemes() const;
 
-    /** Returns the recorded state of a preset.
-     * @param name name of preset
+    /**
+     * Returns the recorded state of a map theme.
      */
-    PresetRecord presetState( const QString& name ) const;
+    MapThemeRecord mapThemeState( const QString& name ) const;
 
-    /** Returns the list of layer IDs that should be visible for the specified preset.
+    /**
+     * Returns the list of layer IDs that are visible for the specified map theme.
+     *
      * @note The order of the returned list is not guaranteed to reflect the order of layers
      * in the canvas.
-     * @param name preset name
      */
-    QStringList presetVisibleLayers( const QString& name ) const;
+    QStringList mapThemeVisibleLayers( const QString& name ) const;
 
-    /** Apply check states of legend nodes of a given layer as defined in the preset.
-     * @param name preset name
-     * @param layerID layer ID
+    /**
+     * Apply check states of legend nodes of a given layer as defined in the map theme.
      */
-    void applyPresetCheckedLegendNodesToLayer( const QString& name, const QString& layerID );
+    void applyMapThemeCheckedLegendNodesToLayer( const QString& name, const QString& layerID );
 
-    /** Get layer style overrides (for QgsMapSettings) of the visible layers for given preset.
-     * @param name preset name
+    /**
+     * Get layer style overrides (for QgsMapSettings) of the visible layers for given map theme.
      */
-    QMap<QString, QString> presetStyleOverrides( const QString& name );
+    QMap<QString, QString> mapThemeStyleOverride( const QString& name );
 
-    /** Reads the preset collection state from XML
+    /**
+     * Reads the map theme collection state from XML
      * @param doc DOM document
-     * @see writeXML
+     * @see writeXml
      */
     void readXml( const QDomDocument& doc );
 
-    /** Writes the preset collection state to XML.
+    /** Writes the map theme collection state to XML.
      * @param doc DOM document
-     * @see readXML
+     * @see readXml
      */
     void writeXml( QDomDocument& doc );
 
-    /** Static method for adding visible layers from a layer tree group to a preset
+    /**
+     * Static method for adding visible layers from a layer tree group to a map theme
      * record.
      * @param parent layer tree group parent
-     * @param rec preset record to amend
+     * @param rec map theme record to amend
      */
-    static void addVisibleLayersToPreset( QgsLayerTreeGroup* parent, PresetRecord& rec );
+    static void addVisibleLayersToMapTheme( QgsLayerTreeGroup* parent, MapThemeRecord& rec );
 
   signals:
 
-    /** Emitted when presets within the collection are changed.
+    /** Emitted when map themes within the collection are changed.
      */
-    void presetsChanged();
-
-  protected slots:
-
-    /** Handles updates of the preset collection when layers are removed from the registry
-     */
-    void registryLayersRemoved( const QStringList& layerIDs );
-
-    //! Update style name if a stored style gets renamed
-    void layerStyleRenamed( const QString& oldName, const QString& newName );
-
-  protected:
-
-    /** Reconnects all preset layers to handle style renames
-     */
-    void reconnectToLayersStyleManager();
+    void mapThemesChanged();
 };
 
diff --git a/src/app/composer/qgscomposermapwidget.cpp b/src/app/composer/qgscomposermapwidget.cpp
index 9883e813bae..e43ac8978ac 100644
--- a/src/app/composer/qgscomposermapwidget.cpp
+++ b/src/app/composer/qgscomposermapwidget.cpp
@@ -158,7 +158,7 @@ void QgsComposerMapWidget::aboutToShowKeepLayersVisibilityPresetsMenu()
     return;
 
   menu->clear();
-  Q_FOREACH ( const QString& presetName, QgsProject::instance()->mapThemeCollection()->presets() )
+  Q_FOREACH ( const QString& presetName, QgsProject::instance()->mapThemeCollection()->mapThemes() )
   {
     menu->addAction( presetName, this, SLOT( keepLayersVisibilityPresetSelected() ) );
   }
@@ -206,7 +206,7 @@ void QgsComposerMapWidget::keepLayersVisibilityPresetSelected()
 
     mKeepLayerStylesCheckBox->setChecked( true );
 
-    mComposerMap->setLayerStyleOverrides( QgsProject::instance()->mapThemeCollection()->presetStyleOverrides( presetName ) );
+    mComposerMap->setLayerStyleOverrides( QgsProject::instance()->mapThemeCollection()->mapThemeStyleOverride( presetName ) );
 
     mComposerMap->cache();
     mComposerMap->update();
@@ -219,7 +219,7 @@ void QgsComposerMapWidget::onPresetsChanged()
   {
     QStringList lst;
     lst.append( tr( "(none)" ) );
-    lst += QgsProject::instance()->mapThemeCollection()->presets();
+    lst += QgsProject::instance()->mapThemeCollection()->mapThemes();
     model->setStringList( lst );
 
     // select the previously selected item again
diff --git a/src/app/main.cpp b/src/app/main.cpp
index c67fdeda7e0..6b671995f92 100644
--- a/src/app/main.cpp
+++ b/src/app/main.cpp
@@ -1200,7 +1200,7 @@ int main( int argc, char *argv[] )
     QList< QPair<QgsVectorLayer *, int > > layers;
     if ( !dxfPreset.isEmpty() )
     {
-      Q_FOREACH ( const QString& layer, QgsProject::instance()->mapThemeCollection()->presetVisibleLayers( dxfPreset ) )
+      Q_FOREACH ( const QString& layer, QgsProject::instance()->mapThemeCollection()->mapThemeVisibleLayers( dxfPreset ) )
       {
         QgsVectorLayer *vl = qobject_cast<QgsVectorLayer *>( QgsMapLayerRegistry::instance()->mapLayer( layer ) );
         if ( !vl )
diff --git a/src/app/qgsdxfexportdialog.cpp b/src/app/qgsdxfexportdialog.cpp
index f1a0f90f94c..580b9d60708 100644
--- a/src/app/qgsdxfexportdialog.cpp
+++ b/src/app/qgsdxfexportdialog.cpp
@@ -346,7 +346,7 @@ void QgsVectorLayerAndAttributeModel::applyVisibilityPreset( const QString &name
   }
   else
   {
-    visibleLayers = QgsProject::instance()->mapThemeCollection()->presetVisibleLayers( name ).toSet();
+    visibleLayers = QgsProject::instance()->mapThemeCollection()->mapThemeVisibleLayers( name ).toSet();
   }
 
   if ( visibleLayers.isEmpty() )
@@ -452,7 +452,7 @@ QgsDxfExportDialog::QgsDxfExportDialog( QWidget *parent, Qt::WindowFlags f )
   mLayerTitleAsName->setChecked( QgsProject::instance()->readEntry( "dxf", "/lastDxfLayerTitleAsName", s.value( "qgis/lastDxfLayerTitleAsName", "false" ).toString() ) != "false" );
   mMapExtentCheckBox->setChecked( QgsProject::instance()->readEntry( "dxf", "/lastDxfMapRectangle", s.value( "qgis/lastDxfMapRectangle", "false" ).toString() ) != "false" );
 
-  QStringList ids = QgsProject::instance()->mapThemeCollection()->presets();
+  QStringList ids = QgsProject::instance()->mapThemeCollection()->mapThemes();
   ids.prepend( "" );
   mVisibilityPresets->addItems( ids );
   mVisibilityPresets->setCurrentIndex( mVisibilityPresets->findText( QgsProject::instance()->readEntry( "dxf", "/lastVisibliltyPreset", "" ) ) );
diff --git a/src/app/qgsmapthemes.cpp b/src/app/qgsmapthemes.cpp
index 404804828ba..5408ce012f3 100644
--- a/src/app/qgsmapthemes.cpp
+++ b/src/app/qgsmapthemes.cpp
@@ -55,11 +55,11 @@ QgsMapThemes::QgsMapThemes()
   connect( mMenu, SIGNAL( aboutToShow() ), this, SLOT( menuAboutToShow() ) );
 }
 
-void QgsMapThemes::addPerLayerCheckedLegendSymbols( QgsMapThemeCollection::PresetRecord& rec )
+void QgsMapThemes::addPerLayerCheckedLegendSymbols( QgsMapThemeCollection::MapThemeRecord& rec )
 {
   QgsLayerTreeModel* model = QgisApp::instance()->layerTreeView()->layerTreeModel();
 
-  Q_FOREACH ( const QString& layerID, rec.mVisibleLayerIDs )
+  Q_FOREACH ( const QString& layerID, rec.visibleLayerIds() )
   {
     QgsLayerTreeLayer* nodeLayer = model->rootGroup()->findLayer( layerID );
     if ( !nodeLayer )
@@ -81,30 +81,37 @@ void QgsMapThemes::addPerLayerCheckedLegendSymbols( QgsMapThemeCollection::Prese
       }
     }
 
+    QMap<QString, QSet<QString> > checkedSymbols = rec.perLayerCheckedLegendSymbols();
+
     if ( hasCheckableItems && someItemsUnchecked )
-      rec.mPerLayerCheckedLegendSymbols.insert( nodeLayer->layerId(), checkedItems );
+      checkedSymbols.insert( nodeLayer->layerId(), checkedItems );
+
+    rec.setPerLayerCheckedLegendSymbols( checkedSymbols );
   }
 }
 
-void QgsMapThemes::addPerLayerCurrentStyle( QgsMapThemeCollection::PresetRecord& rec )
+void QgsMapThemes::addPerLayerCurrentStyle( QgsMapThemeCollection::MapThemeRecord& rec )
 {
   QgsLayerTreeModel* model = QgisApp::instance()->layerTreeView()->layerTreeModel();
 
-  Q_FOREACH ( const QString& layerID, rec.mVisibleLayerIDs )
+  QMap<QString, QString> styles = rec.perLayerCurrentStyle();
+
+  Q_FOREACH ( const QString& layerID, rec.visibleLayerIds() )
   {
     QgsLayerTreeLayer* nodeLayer = model->rootGroup()->findLayer( layerID );
     if ( !nodeLayer )
       continue;
 
-    rec.mPerLayerCurrentStyle[layerID] = nodeLayer->layer()->styleManager()->currentStyle();
+    styles[layerID] = nodeLayer->layer()->styleManager()->currentStyle();
   }
+  rec.setPerLayerCurrentStyle( styles );
 }
 
-QgsMapThemeCollection::PresetRecord QgsMapThemes::currentState()
+QgsMapThemeCollection::MapThemeRecord QgsMapThemes::currentState()
 {
-  QgsMapThemeCollection::PresetRecord rec;
+  QgsMapThemeCollection::MapThemeRecord rec;
   QgsLayerTreeGroup* root = QgsProject::instance()->layerTreeRoot();
-  QgsMapThemeCollection::addVisibleLayersToPreset( root, rec );
+  QgsMapThemeCollection::addVisibleLayersToMapTheme( root, rec );
   addPerLayerCheckedLegendSymbols( rec );
   addPerLayerCurrentStyle( rec );
   return rec;
@@ -130,7 +137,7 @@ void QgsMapThemes::updatePreset( const QString& name )
 
 QStringList QgsMapThemes::orderedPresetVisibleLayers( const QString& name ) const
 {
-  QStringList visibleIds = QgsProject::instance()->mapThemeCollection()->presetVisibleLayers( name );
+  QStringList visibleIds = QgsProject::instance()->mapThemeCollection()->mapThemeVisibleLayers( name );
 
   // also make sure to order the layers according to map canvas order
   QgsLayerTreeMapCanvasBridge* bridge = QgisApp::instance()->layerTreeCanvasBridge();
@@ -153,7 +160,7 @@ QMenu* QgsMapThemes::menu()
 
 void QgsMapThemes::addPreset()
 {
-  QStringList existingNames = QgsProject::instance()->mapThemeCollection()->presets();
+  QStringList existingNames = QgsProject::instance()->mapThemeCollection()->mapThemes();
   QgsNewNameDialog dlg( tr( "theme" ) , tr( "Theme" ), QStringList(), existingNames, QRegExp(), Qt::CaseInsensitive, mMenu );
   dlg.setWindowTitle( tr( "Map Themes" ) );
   dlg.setHintString( tr( "Name of the new theme" ) );
@@ -185,7 +192,7 @@ void QgsMapThemes::replaceTriggered()
   addPreset( actionPreset->text() );
 }
 
-void QgsMapThemes::applyStateToLayerTreeGroup( QgsLayerTreeGroup* parent, const QgsMapThemeCollection::PresetRecord& rec )
+void QgsMapThemes::applyStateToLayerTreeGroup( QgsLayerTreeGroup* parent, const QgsMapThemeCollection::MapThemeRecord& rec )
 {
   Q_FOREACH ( QgsLayerTreeNode* node, parent->children() )
   {
@@ -194,21 +201,21 @@ void QgsMapThemes::applyStateToLayerTreeGroup( QgsLayerTreeGroup* parent, const
     else if ( QgsLayerTree::isLayer( node ) )
     {
       QgsLayerTreeLayer* nodeLayer = QgsLayerTree::toLayer( node );
-      bool isVisible = rec.mVisibleLayerIDs.contains( nodeLayer->layerId() );
+      bool isVisible = rec.visibleLayerIds().contains( nodeLayer->layerId() );
       nodeLayer->setVisible( isVisible ? Qt::Checked : Qt::Unchecked );
 
       if ( isVisible )
       {
-        if ( rec.mPerLayerCurrentStyle.contains( nodeLayer->layerId() ) )
+        if ( rec.perLayerCurrentStyle().contains( nodeLayer->layerId() ) )
         {
           // apply desired style first
-          nodeLayer->layer()->styleManager()->setCurrentStyle( rec.mPerLayerCurrentStyle[nodeLayer->layerId()] );
+          nodeLayer->layer()->styleManager()->setCurrentStyle( rec.perLayerCurrentStyle().value( nodeLayer->layerId() ) );
         }
 
         QgsLayerTreeModel* model = QgisApp::instance()->layerTreeView()->layerTreeModel();
-        if ( rec.mPerLayerCheckedLegendSymbols.contains( nodeLayer->layerId() ) )
+        if ( rec.perLayerCheckedLegendSymbols().contains( nodeLayer->layerId() ) )
         {
-          const QSet<QString>& checkedNodes = rec.mPerLayerCheckedLegendSymbols[nodeLayer->layerId()];
+          const QSet<QString>& checkedNodes = rec.perLayerCheckedLegendSymbols().value( nodeLayer->layerId() );
           // some nodes are not checked
           Q_FOREACH ( QgsLayerTreeModelLegendNode* legendNode, model->layerLegendNodes( nodeLayer ) )
           {
@@ -236,10 +243,10 @@ void QgsMapThemes::applyStateToLayerTreeGroup( QgsLayerTreeGroup* parent, const
 
 void QgsMapThemes::applyState( const QString& presetName )
 {
-  if ( !QgsProject::instance()->mapThemeCollection()->hasPreset( presetName ) )
+  if ( !QgsProject::instance()->mapThemeCollection()->hasMapTheme( presetName ) )
     return;
 
-  applyStateToLayerTreeGroup( QgsProject::instance()->layerTreeRoot(), QgsProject::instance()->mapThemeCollection()->presetState( presetName ) );
+  applyStateToLayerTreeGroup( QgsProject::instance()->layerTreeRoot(), QgsProject::instance()->mapThemeCollection()->mapThemeState( presetName ) );
 
   // also make sure that the preset is up-to-date (not containing any non-existent legend items)
   QgsProject::instance()->mapThemeCollection()->update( presetName, currentState() );
@@ -251,7 +258,7 @@ void QgsMapThemes::removeCurrentPreset()
   {
     if ( a->isChecked() )
     {
-      QgsProject::instance()->mapThemeCollection()->removePreset( a->text() );
+      QgsProject::instance()->mapThemeCollection()->removeMapTheme( a->text() );
       break;
     }
   }
@@ -265,14 +272,14 @@ void QgsMapThemes::menuAboutToShow()
   qDeleteAll( mMenuReplaceActions );
   mMenuReplaceActions.clear();
 
-  QgsMapThemeCollection::PresetRecord rec = currentState();
+  QgsMapThemeCollection::MapThemeRecord rec = currentState();
   bool hasCurrent = false;
 
-  Q_FOREACH ( const QString& grpName, QgsProject::instance()->mapThemeCollection()->presets() )
+  Q_FOREACH ( const QString& grpName, QgsProject::instance()->mapThemeCollection()->mapThemes() )
   {
     QAction* a = new QAction( grpName, mMenu );
     a->setCheckable( true );
-    if ( !hasCurrent && rec == QgsProject::instance()->mapThemeCollection()->presetState( grpName ) )
+    if ( !hasCurrent && rec == QgsProject::instance()->mapThemeCollection()->mapThemeState( grpName ) )
     {
       a->setChecked( true );
       hasCurrent = true;
diff --git a/src/app/qgsmapthemes.h b/src/app/qgsmapthemes.h
index 8af5b7b3eff..3b2fa802c42 100644
--- a/src/app/qgsmapthemes.h
+++ b/src/app/qgsmapthemes.h
@@ -74,14 +74,14 @@ class APP_EXPORT QgsMapThemes : public QObject
     QgsMapThemes(); // singleton
 
     //! Applies current layer state to a preset record
-    void applyStateToLayerTreeGroup( QgsLayerTreeGroup* parent, const QgsMapThemeCollection::PresetRecord& rec );
+    void applyStateToLayerTreeGroup( QgsLayerTreeGroup* parent, const QgsMapThemeCollection::MapThemeRecord& rec );
     //! Applies layer checked legend symbols to a preset record
-    void addPerLayerCheckedLegendSymbols( QgsMapThemeCollection::PresetRecord& rec );
+    void addPerLayerCheckedLegendSymbols( QgsMapThemeCollection::MapThemeRecord& rec );
     //! Applies current layer styles to a preset record
-    void addPerLayerCurrentStyle( QgsMapThemeCollection::PresetRecord& rec );
+    void addPerLayerCurrentStyle( QgsMapThemeCollection::MapThemeRecord& rec );
 
     //! Returns the current state of the map canvas as a preset record
-    QgsMapThemeCollection::PresetRecord currentState();
+    QgsMapThemeCollection::MapThemeRecord currentState();
 
     //! Applies a preset for the project's collection to the canvas
     void applyState( const QString& presetName );
diff --git a/src/core/composer/qgscomposermap.cpp b/src/core/composer/qgscomposermap.cpp
index cb7942c1143..7b1ddb35ffa 100644
--- a/src/core/composer/qgscomposermap.cpp
+++ b/src/core/composer/qgscomposermap.cpp
@@ -537,8 +537,8 @@ QStringList QgsComposerMap::layersToRender( const QgsExpressionContext* context
       presetName = exprVal.toString();
     }
 
-    if ( QgsProject::instance()->mapThemeCollection()->hasPreset( presetName ) )
-      renderLayerSet = QgsProject::instance()->mapThemeCollection()->presetVisibleLayers( presetName );
+    if ( QgsProject::instance()->mapThemeCollection()->hasMapTheme( presetName ) )
+      renderLayerSet = QgsProject::instance()->mapThemeCollection()->mapThemeVisibleLayers( presetName );
     else  // fallback to using map canvas layers
       renderLayerSet = mComposition->mapSettings().layers();
   }
@@ -598,8 +598,8 @@ QMap<QString, QString> QgsComposerMap::layerStyleOverridesToRender( const QgsExp
       presetName = exprVal.toString();
     }
 
-    if ( QgsProject::instance()->mapThemeCollection()->hasPreset( presetName ) )
-      return QgsProject::instance()->mapThemeCollection()->presetStyleOverrides( presetName );
+    if ( QgsProject::instance()->mapThemeCollection()->hasMapTheme( presetName ) )
+      return QgsProject::instance()->mapThemeCollection()->mapThemeStyleOverride( presetName );
     else
       return QMap<QString, QString>();
   }
diff --git a/src/core/qgsmapthemecollection.cpp b/src/core/qgsmapthemecollection.cpp
index 60b07404d25..41e742ef2e5 100644
--- a/src/core/qgsmapthemecollection.cpp
+++ b/src/core/qgsmapthemecollection.cpp
@@ -32,85 +32,85 @@ QgsMapThemeCollection::QgsMapThemeCollection()
            this, SLOT( registryLayersRemoved( QStringList ) ) );
 }
 
-void QgsMapThemeCollection::addVisibleLayersToPreset( QgsLayerTreeGroup* parent, QgsMapThemeCollection::PresetRecord& rec )
+void QgsMapThemeCollection::addVisibleLayersToMapTheme( QgsLayerTreeGroup* parent, QgsMapThemeCollection::MapThemeRecord& rec )
 {
   Q_FOREACH ( QgsLayerTreeNode* node, parent->children() )
   {
     if ( QgsLayerTree::isGroup( node ) )
-      addVisibleLayersToPreset( QgsLayerTree::toGroup( node ), rec );
+      addVisibleLayersToMapTheme( QgsLayerTree::toGroup( node ), rec );
     else if ( QgsLayerTree::isLayer( node ) )
     {
       QgsLayerTreeLayer* nodeLayer = QgsLayerTree::toLayer( node );
       if ( nodeLayer->isVisible() )
-        rec.mVisibleLayerIDs << nodeLayer->layerId();
+        rec.mVisibleLayerIds << nodeLayer->layerId();
     }
   }
 }
 
-bool QgsMapThemeCollection::hasPreset( const QString& name ) const
+bool QgsMapThemeCollection::hasMapTheme( const QString& name ) const
 {
-  return mPresets.contains( name );
+  return mMapThemes.contains( name );
 }
 
-void QgsMapThemeCollection::insert( const QString& name, const QgsMapThemeCollection::PresetRecord& state )
+void QgsMapThemeCollection::insert( const QString& name, const QgsMapThemeCollection::MapThemeRecord& state )
 {
-  mPresets.insert( name, state );
+  mMapThemes.insert( name, state );
 
   reconnectToLayersStyleManager();
-  emit presetsChanged();
+  emit mapThemesChanged();
 }
 
-void QgsMapThemeCollection::update( const QString& name, const PresetRecord& state )
+void QgsMapThemeCollection::update( const QString& name, const MapThemeRecord& state )
 {
-  if ( !mPresets.contains( name ) )
+  if ( !mMapThemes.contains( name ) )
     return;
 
-  mPresets[name] = state;
+  mMapThemes[name] = state;
 
   reconnectToLayersStyleManager();
-  emit presetsChanged();
+  emit mapThemesChanged();
 }
 
-void QgsMapThemeCollection::removePreset( const QString& name )
+void QgsMapThemeCollection::removeMapTheme( const QString& name )
 {
-  if ( !mPresets.contains( name ) )
+  if ( !mMapThemes.contains( name ) )
     return;
 
-  mPresets.remove( name );
+  mMapThemes.remove( name );
 
   reconnectToLayersStyleManager();
-  emit presetsChanged();
+  emit mapThemesChanged();
 }
 
 void QgsMapThemeCollection::clear()
 {
-  mPresets.clear();
+  mMapThemes.clear();
 
   reconnectToLayersStyleManager();
-  emit presetsChanged();
+  emit mapThemesChanged();
 }
 
-QStringList QgsMapThemeCollection::presets() const
+QStringList QgsMapThemeCollection::mapThemes() const
 {
-  return mPresets.keys();
+  return mMapThemes.keys();
 }
 
-QStringList QgsMapThemeCollection::presetVisibleLayers( const QString& name ) const
+QStringList QgsMapThemeCollection::mapThemeVisibleLayers( const QString& name ) const
 {
-  return mPresets.value( name ).mVisibleLayerIDs;
+  return mMapThemes.value( name ).mVisibleLayerIds;
 }
 
 
-void QgsMapThemeCollection::applyPresetCheckedLegendNodesToLayer( const QString& name, const QString& layerID )
+void QgsMapThemeCollection::applyMapThemeCheckedLegendNodesToLayer( const QString& name, const QString& layerID )
 {
-  if ( !mPresets.contains( name ) )
+  if ( !mMapThemes.contains( name ) )
     return;
 
   QgsMapLayer* layer = QgsMapLayerRegistry::instance()->mapLayer( layerID );
   if ( !layer )
     return;
 
-  const PresetRecord& rec = mPresets[name];
+  const MapThemeRecord& rec = mMapThemes[name];
 
   QgsVectorLayer* vlayer = qobject_cast<QgsVectorLayer*>( layer );
   if ( !vlayer || !vlayer->renderer() )
@@ -131,14 +131,14 @@ void QgsMapThemeCollection::applyPresetCheckedLegendNodesToLayer( const QString&
 }
 
 
-QMap<QString, QString> QgsMapThemeCollection::presetStyleOverrides( const QString& presetName )
+QMap<QString, QString> QgsMapThemeCollection::mapThemeStyleOverride( const QString& presetName )
 {
   QMap<QString, QString> styleOverrides;
-  if ( !mPresets.contains( presetName ) )
+  if ( !mMapThemes.contains( presetName ) )
     return styleOverrides;
 
-  QStringList lst = presetVisibleLayers( presetName );
-  const QgsMapThemeCollection::PresetRecord& rec = mPresets[presetName];
+  QStringList lst = mapThemeVisibleLayers( presetName );
+  const QgsMapThemeCollection::MapThemeRecord& rec = mMapThemes[presetName];
   Q_FOREACH ( const QString& layerID, lst )
   {
     QgsMapLayer* layer = QgsMapLayerRegistry::instance()->mapLayer( layerID );
@@ -152,7 +152,7 @@ QMap<QString, QString> QgsMapThemeCollection::presetStyleOverrides( const QStrin
     layer->styleManager()->setOverrideStyle( overrideStyleName );
 
     // set the checked legend nodes
-    applyPresetCheckedLegendNodesToLayer( presetName, layerID );
+    applyMapThemeCheckedLegendNodesToLayer( presetName, layerID );
 
     // save to overrides
     QgsMapLayerStyle layerStyle;
@@ -169,10 +169,10 @@ void QgsMapThemeCollection::reconnectToLayersStyleManager()
   // disconnect( 0, 0, this, SLOT( layerStyleRenamed( QString, QString ) ) );
 
   QSet<QString> layerIDs;
-  PresetRecordMap::const_iterator it = mPresets.constBegin();
-  for ( ; it != mPresets.constEnd(); ++it )
+  MapThemeRecordMap::const_iterator it = mMapThemes.constBegin();
+  for ( ; it != mMapThemes.constEnd(); ++it )
   {
-    const PresetRecord& rec = it.value();
+    const MapThemeRecord& rec = it.value();
     QMap<QString, QString>::const_iterator layerIt = rec.mPerLayerCurrentStyle.constBegin();
     for ( ; layerIt != rec.mPerLayerCurrentStyle.constEnd(); ++layerIt )
       layerIDs << layerIt.key();
@@ -197,14 +197,14 @@ void QgsMapThemeCollection::readXml( const QDomDocument& doc )
   while ( !visPresetElem.isNull() )
   {
     QString presetName = visPresetElem.attribute( "name" );
-    PresetRecord rec;
+    MapThemeRecord rec;
     QDomElement visPresetLayerElem = visPresetElem.firstChildElement( "layer" );
     while ( !visPresetLayerElem.isNull() )
     {
       QString layerID = visPresetLayerElem.attribute( "id" );
       if ( QgsMapLayerRegistry::instance()->mapLayer( layerID ) )
       {
-        rec.mVisibleLayerIDs << layerID; // only use valid layer IDs
+        rec.mVisibleLayerIds << layerID; // only use valid layer IDs
         if ( visPresetLayerElem.hasAttribute( "style" ) )
           rec.mPerLayerCurrentStyle[layerID] = visPresetLayerElem.attribute( "style" );
       }
@@ -229,26 +229,26 @@ void QgsMapThemeCollection::readXml( const QDomDocument& doc )
       checkedLegendNodesElem = checkedLegendNodesElem.nextSiblingElement( "checked-legend-nodes" );
     }
 
-    mPresets.insert( presetName, rec );
+    mMapThemes.insert( presetName, rec );
 
     visPresetElem = visPresetElem.nextSiblingElement( "visibility-preset" );
   }
 
   reconnectToLayersStyleManager();
-  emit presetsChanged();
+  emit mapThemesChanged();
 }
 
 void QgsMapThemeCollection::writeXml( QDomDocument& doc )
 {
   QDomElement visPresetsElem = doc.createElement( "visibility-presets" );
-  PresetRecordMap::const_iterator it = mPresets.constBegin();
-  for ( ; it != mPresets.constEnd(); ++ it )
+  MapThemeRecordMap::const_iterator it = mMapThemes.constBegin();
+  for ( ; it != mMapThemes.constEnd(); ++ it )
   {
     QString grpName = it.key();
-    const PresetRecord& rec = it.value();
+    const MapThemeRecord& rec = it.value();
     QDomElement visPresetElem = doc.createElement( "visibility-preset" );
     visPresetElem.setAttribute( "name", grpName );
-    Q_FOREACH ( const QString& layerID, rec.mVisibleLayerIDs )
+    Q_FOREACH ( const QString& layerID, rec.mVisibleLayerIds )
     {
       QDomElement layerElem = doc.createElement( "layer" );
       layerElem.setAttribute( "id", layerID );
@@ -282,16 +282,16 @@ void QgsMapThemeCollection::registryLayersRemoved( const QStringList& layerIDs )
 {
   Q_FOREACH ( const QString& layerID, layerIDs )
   {
-    PresetRecordMap::iterator it = mPresets.begin();
-    for ( ; it != mPresets.end(); ++it )
+    MapThemeRecordMap::iterator it = mMapThemes.begin();
+    for ( ; it != mMapThemes.end(); ++it )
     {
-      PresetRecord& rec = it.value();
-      rec.mVisibleLayerIDs.removeAll( layerID );
+      MapThemeRecord& rec = it.value();
+      rec.mVisibleLayerIds.removeAll( layerID );
       rec.mPerLayerCheckedLegendSymbols.remove( layerID );
       rec.mPerLayerCurrentStyle.remove( layerID );
     }
   }
-  emit presetsChanged();
+  emit mapThemesChanged();
 }
 
 void QgsMapThemeCollection::layerStyleRenamed( const QString& oldName, const QString& newName )
@@ -302,10 +302,10 @@ void QgsMapThemeCollection::layerStyleRenamed( const QString& oldName, const QSt
 
   QString layerID = styleMgr->layer()->id();
 
-  PresetRecordMap::iterator it = mPresets.begin();
-  for ( ; it != mPresets.end(); ++it )
+  MapThemeRecordMap::iterator it = mMapThemes.begin();
+  for ( ; it != mMapThemes.end(); ++it )
   {
-    PresetRecord& rec = it.value();
+    MapThemeRecord& rec = it.value();
 
     if ( rec.mPerLayerCurrentStyle.contains( layerID ) )
     {
@@ -314,5 +314,35 @@ void QgsMapThemeCollection::layerStyleRenamed( const QString& oldName, const QSt
         rec.mPerLayerCurrentStyle[layerID] = newName;
     }
   }
-  emit presetsChanged();
+  emit mapThemesChanged();
+}
+
+QStringList QgsMapThemeCollection::MapThemeRecord::visibleLayerIds() const
+{
+  return mVisibleLayerIds;
+}
+
+void QgsMapThemeCollection::MapThemeRecord::setVisibleLayerIds( const QStringList& visibleLayerIds )
+{
+  mVisibleLayerIds = visibleLayerIds;
+}
+
+QMap<QString, QSet<QString> > QgsMapThemeCollection::MapThemeRecord::perLayerCheckedLegendSymbols() const
+{
+  return mPerLayerCheckedLegendSymbols;
+}
+
+void QgsMapThemeCollection::MapThemeRecord::setPerLayerCheckedLegendSymbols( const QMap<QString, QSet<QString> >& perLayerCheckedLegendSymbols )
+{
+  mPerLayerCheckedLegendSymbols = perLayerCheckedLegendSymbols;
+}
+
+QMap<QString, QString> QgsMapThemeCollection::MapThemeRecord::perLayerCurrentStyle() const
+{
+  return mPerLayerCurrentStyle;
+}
+
+void QgsMapThemeCollection::MapThemeRecord::setPerLayerCurrentStyle( const QMap<QString, QString>& perLayerCurrentStyle )
+{
+  mPerLayerCurrentStyle = perLayerCurrentStyle;
 }
diff --git a/src/core/qgsmapthemecollection.h b/src/core/qgsmapthemecollection.h
index ddb02ae9bf3..b203f38f42c 100644
--- a/src/core/qgsmapthemecollection.h
+++ b/src/core/qgsmapthemecollection.h
@@ -37,134 +37,193 @@ class CORE_EXPORT QgsMapThemeCollection : public QObject
 {
     Q_OBJECT
 
+    Q_PROPERTY( QStringList mapThemes READ mapThemes NOTIFY mapThemesChanged )
+
   public:
 
-    /** \ingroup core
-     * Individual preset record of visible layers and styles.
+    /**
+     * \ingroup core
+     * Individual map theme record of visible layers and styles.
+     *
+     * @note Added in QGIS 3.0, Previously called PresetRecord
      */
-    class PresetRecord
+    class MapThemeRecord
     {
       public:
 
-        bool operator==( const PresetRecord& other ) const
+        bool operator==( const MapThemeRecord& other ) const
         {
-          return mVisibleLayerIDs.toSet() == other.mVisibleLayerIDs.toSet()
+          return mVisibleLayerIds.toSet() == other.mVisibleLayerIds.toSet()
                  && mPerLayerCheckedLegendSymbols == other.mPerLayerCheckedLegendSymbols
                  && mPerLayerCurrentStyle == other.mPerLayerCurrentStyle;
         }
-        bool operator!=( const PresetRecord& other ) const
+        bool operator!=( const MapThemeRecord& other ) const
         {
           return !( *this == other );
         }
 
-        //! Ordered list of layers that are visible
-        QStringList mVisibleLayerIDs;
-        /** For layers that have checkable legend symbols and not all symbols are checked - list which ones are
-         * @note not available in Python bindings
+        /**
+         * Ordered list of visible layers
+         * @note Added in QGIS 3.0
          */
+        QStringList visibleLayerIds() const;
+
+        /**
+         * Ordered list of visible layers
+         * @note Added in QGIS 3.0
+         */
+        void setVisibleLayerIds( const QStringList& visibleLayerIds );
+
+        /**
+         * Lists which legend symbols are checked for layers which support this and where
+         * not all symbols are checked.
+         * @note not available in Python bindings
+         * @note Added in QGIS 3.0
+         */
+        QMap<QString, QSet<QString> > perLayerCheckedLegendSymbols() const;
+
+        /**
+         * Lists which legend symbols are checked for layers which support this and where
+         * not all symbols are checked.
+         * @note not available in Python bindings
+         * @note Added in QGIS 3.0
+         */
+        void setPerLayerCheckedLegendSymbols( const QMap<QString, QSet<QString> >& perLayerCheckedLegendSymbols );
+
+        /**
+         * The currently used style name for layers with multiple styles.
+         * The map has layer ids as keys and style names as values.
+         * @note Added in QGIS 3.0
+         */
+        QMap<QString, QString> perLayerCurrentStyle() const;
+
+        /**
+         * The currently used style name for layers with multiple styles.
+         * The map has layer ids as keys and style names as values.
+         * @note Added in QGIS 3.0
+         */
+        void setPerLayerCurrentStyle( const QMap<QString, QString>& perLayerCurrentStyle );
+
+      private:
+        QStringList mVisibleLayerIds;
         QMap<QString, QSet<QString> > mPerLayerCheckedLegendSymbols;
-        //! For layers that use multiple styles - which one is currently selected
         QMap<QString, QString> mPerLayerCurrentStyle;
+
+        friend class QgsMapThemeCollection;
     };
 
     QgsMapThemeCollection();
 
-    /** Returns whether a preset with a matching name exists.
-     * @param name name of preset to check
-     * @returns true if preset exists
+    /**
+     * Returns whether a map theme with a matching name exists.
+     * @note Added in QGIS 3.0
      */
-    bool hasPreset( const QString& name ) const;
+    bool hasMapTheme( const QString& name ) const;
 
-    /** Inserts a new preset to the collection.
-     * @param name name of preset
-     * @param state preset record
+    /**
+     * Inserts a new map theme to the collection.
      * @see update()
      */
-    void insert( const QString& name, const PresetRecord& state );
+    void insert( const QString& name, const MapThemeRecord& state );
 
-    /** Updates a preset within the collection.
-     * @param name name of preset to update
-     * @param state preset record to replace existing preset
+    /**
+     * Updates a map theme within the collection.
+     * @param name name of map theme to update
+     * @param state map theme record to replace existing map theme
      * @see insert()
      */
-    void update( const QString& name, const PresetRecord& state );
+    void update( const QString& name, const MapThemeRecord& state );
 
-    /** Remove existing preset from collection.
-     * @param name preset name
+    /**
+     * Remove an existing map theme from collection.
+     * @note Added in QGIS 3.0
      */
-    void removePreset( const QString& name );
+    void removeMapTheme( const QString& name );
 
-    //! Remove all presets from the collection.
+    //! Remove all map themes from the collection.
     void clear();
 
-    //! Returns a list of existing preset names.
-    QStringList presets() const;
-
-    /** Returns the recorded state of a preset.
-     * @param name name of preset
+    /**
+     * Returns a list of existing map theme names.
+     * @note Added in QGIS 3.0
      */
-    PresetRecord presetState( const QString& name ) const { return mPresets[name]; }
+    QStringList mapThemes() const;
 
-    /** Returns the list of layer IDs that should be visible for the specified preset.
+    /**
+     * Returns the recorded state of a map theme.
+     * @note Added in QGIS 3.0
+     */
+    MapThemeRecord mapThemeState( const QString& name ) const { return mMapThemes[name]; }
+
+    /**
+     * Returns the list of layer IDs that are visible for the specified map theme.
+     *
      * @note The order of the returned list is not guaranteed to reflect the order of layers
      * in the canvas.
-     * @param name preset name
+     * @note Added in QGIS 3.0
      */
-    QStringList presetVisibleLayers( const QString& name ) const;
+    QStringList mapThemeVisibleLayers( const QString& name ) const;
 
-    /** Apply check states of legend nodes of a given layer as defined in the preset.
-     * @param name preset name
-     * @param layerID layer ID
+    /**
+     * Apply check states of legend nodes of a given layer as defined in the map theme.
+     * @note Added in QGIS 3.0
      */
-    void applyPresetCheckedLegendNodesToLayer( const QString& name, const QString& layerID );
+    void applyMapThemeCheckedLegendNodesToLayer( const QString& name, const QString& layerID );
 
-    /** Get layer style overrides (for QgsMapSettings) of the visible layers for given preset.
-     * @param name preset name
+    /**
+     * Get layer style overrides (for QgsMapSettings) of the visible layers for given map theme.
+     * @note Added in QGIS 3.0
      */
-    QMap<QString, QString> presetStyleOverrides( const QString& name );
+    QMap<QString, QString> mapThemeStyleOverride( const QString& name );
 
-    /** Reads the preset collection state from XML
+    /**
+     * Reads the map theme collection state from XML
      * @param doc DOM document
      * @see writeXml
      */
     void readXml( const QDomDocument& doc );
 
-    /** Writes the preset collection state to XML.
+    /** Writes the map theme collection state to XML.
      * @param doc DOM document
      * @see readXml
      */
     void writeXml( QDomDocument& doc );
 
-    /** Static method for adding visible layers from a layer tree group to a preset
+    /**
+     * Static method for adding visible layers from a layer tree group to a map theme
      * record.
      * @param parent layer tree group parent
-     * @param rec preset record to amend
+     * @param rec map theme record to amend
      */
-    static void addVisibleLayersToPreset( QgsLayerTreeGroup* parent, PresetRecord& rec );
+    static void addVisibleLayersToMapTheme( QgsLayerTreeGroup* parent, MapThemeRecord& rec );
 
   signals:
 
-    /** Emitted when presets within the collection are changed.
+    /**
+     * Emitted when map themes within the collection are changed.
+     * @note Added in QGIS 3.0
      */
-    void presetsChanged();
+    void mapThemesChanged();
 
-  protected slots:
+  private slots:
 
-    /** Handles updates of the preset collection when layers are removed from the registry
+    /**
+     * Handles updates of the map theme collection when layers are removed from the registry
      */
     void registryLayersRemoved( const QStringList& layerIDs );
 
     //! Update style name if a stored style gets renamed
     void layerStyleRenamed( const QString& oldName, const QString& newName );
 
-  protected:
+  private:
 
-    /** Reconnects all preset layers to handle style renames
+    /**
+     * Reconnects all map theme layers to handle style renames
      */
     void reconnectToLayersStyleManager();
 
-    typedef QMap<QString, PresetRecord> PresetRecordMap;
-    PresetRecordMap mPresets;
+    typedef QMap<QString, MapThemeRecord> MapThemeRecordMap;
+    MapThemeRecordMap mMapThemes;
 };
 
 
diff --git a/src/core/qgsproject.cpp b/src/core/qgsproject.cpp
index 04d3f84c722..48cbfb9f660 100644
--- a/src/core/qgsproject.cpp
+++ b/src/core/qgsproject.cpp
@@ -480,7 +480,7 @@ void QgsProject::clear()
   mEmbeddedLayers.clear();
   mRelationManager->clear();
 
-  mVisibilityPresetCollection.reset( new QgsMapThemeCollection() );
+  mMapThemeCollection.reset( new QgsMapThemeCollection() );
 
   mRootGroup->removeAllChildren();
 
@@ -916,8 +916,8 @@ bool QgsProject::read()
 
   mRootGroup->removeCustomProperty( "loading" );
 
-  mVisibilityPresetCollection.reset( new QgsMapThemeCollection() );
-  mVisibilityPresetCollection->readXml( *doc );
+  mMapThemeCollection.reset( new QgsMapThemeCollection() );
+  mMapThemeCollection->readXml( *doc );
 
   // reassign change dependencies now that all layers are loaded
   QMap<QString, QgsMapLayer*> existingMaps = QgsMapLayerRegistry::instance()->mapLayers();
@@ -1203,7 +1203,7 @@ bool QgsProject::write()
     imp_->properties_.writeXml( "properties", qgisNode, *doc );
   }
 
-  mVisibilityPresetCollection->writeXml( *doc );
+  mMapThemeCollection->writeXml( *doc );
 
   // now wrap it up and ship it to the project file
   doc->normalize();             // XXX I'm not entirely sure what this does
@@ -2195,7 +2195,7 @@ QgsLayerTreeGroup *QgsProject::layerTreeRoot() const
 
 QgsMapThemeCollection* QgsProject::mapThemeCollection()
 {
-  return mVisibilityPresetCollection.data();
+  return mMapThemeCollection.data();
 }
 
 void QgsProject::setNonIdentifiableLayers( QList<QgsMapLayer*> layers )
diff --git a/src/core/qgsproject.h b/src/core/qgsproject.h
index b912b753290..5905fba5868 100644
--- a/src/core/qgsproject.h
+++ b/src/core/qgsproject.h
@@ -76,6 +76,7 @@ class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenera
     Q_PROPERTY( QString fileName READ fileName WRITE setFileName NOTIFY fileNameChanged )
     Q_PROPERTY( QString homePath READ homePath NOTIFY homePathChanged )
     Q_PROPERTY( QgsCoordinateReferenceSystem crs READ crs WRITE setCrs )
+    Q_PROPERTY( QgsMapThemeCollection* mapThemeCollection READ mapThemeCollection )
 
   public:
 
@@ -615,7 +616,7 @@ class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenera
     //! map of transaction group: QPair( providerKey, connString ) -> transactionGroup
     QMap< QPair< QString, QString>, QgsTransactionGroup*> mTransactionGroups;
 
-    QScopedPointer<QgsMapThemeCollection> mVisibilityPresetCollection;
+    QScopedPointer<QgsMapThemeCollection> mMapThemeCollection;
 };
 
 
diff --git a/tests/src/core/testqgscomposermap.cpp b/tests/src/core/testqgscomposermap.cpp
index 4a6df1b01ec..8bbfe727d05 100644
--- a/tests/src/core/testqgscomposermap.cpp
+++ b/tests/src/core/testqgscomposermap.cpp
@@ -349,9 +349,8 @@ void TestQgsComposerMap::dataDefinedStyles()
   mComposerMap->setFrameEnabled( true );
   mComposition->addComposerMap( mComposerMap );
 
-  QgsMapThemeCollection::PresetRecord rec;
-  rec.mVisibleLayerIDs << mPointsLayer->id();
-  rec.mVisibleLayerIDs << mLinesLayer->id();
+  QgsMapThemeCollection::MapThemeRecord rec;
+  rec.setVisibleLayerIds( QStringList() << mPointsLayer->id() << mLinesLayer->id() );
 
   QgsProject::instance()->mapThemeCollection()->insert( "test preset", rec );