instantiating recording layers model from qml

app/layersproxymodel.cpp

@@ -14,18 +14,9 @@
 #include "qgslayertree.h"
 
 LayersProxyModel::LayersProxyModel( QObject *parent ) :
-    QgsMapLayerProxyModel{ parent }
+  QgsMapLayerProxyModel{ parent },
+  filterFunction( []( QgsMapLayer * layer ) { return ( layer && layer->isValid() ); } ) // default filter
 {
-  switch ( mModelType )
-  {
-    case ActiveLayerSelection:
-      filterFunction = [this]( QgsMapLayer * layer ) { return recordingAllowed( layer ); };
-      break;
-    default:
-      filterFunction = []( QgsMapLayer * ) { return true; };
-      break;
-  } //inherit 2 ocurrences from layer proxy model - layersProxyModel and recordingLayersProxyModel
-
   QObject::connect( this, &LayersProxyModel::rowsInserted, this, &LayersProxyModel::countChanged );
   QObject::connect( this, &LayersProxyModel::rowsRemoved, this, &LayersProxyModel::countChanged );
 }
@@ -174,7 +165,7 @@ void LayersProxyModel::setQgsProject( QgsProject *project )
   }
 }
 
-LayerModelTypes LayersProxyModel::modelType() const
+LayersProxyModel::LayerModelTypes LayersProxyModel::modelType() const
 {
   return mModelType;
 }
@@ -184,6 +175,9 @@ void LayersProxyModel::setModelType( LayerModelTypes type )
   if ( mModelType != type )
   {
     mModelType = type;
+
+    applyFilterFunction();
+
     emit modelTypeChanged();
   }
 }
@@ -202,3 +196,22 @@ void LayersProxyModel::setModel( LayersModel *model )
     emit modelChanged();
   }
 }
+
+void LayersProxyModel::applyFilterFunction()
+{
+  switch ( mModelType )
+  {
+    case ActiveLayerSelection:
+      filterFunction = [this]( QgsMapLayer * layer )
+      {
+        return recordingAllowed( layer );
+      };
+      break;
+    default:
+      filterFunction = []( QgsMapLayer * )
+      {
+        return true;
+      };
+      break;
+  }
+}

app/layersproxymodel.h

@@ -21,24 +21,23 @@
 
 #include "layersmodel.h"
 
-enum LayerModelTypes
-{
-    AllLayers,
-    ActiveLayerSelection
-};
-
 class LayersProxyModel : public QgsMapLayerProxyModel
 {
     Q_OBJECT
 
     Q_PROPERTY( int count READ rowCount NOTIFY countChanged )
-    Q_PROPERTY( QgsProject* qgsProject READ qgsProject WRITE setQgsProject NOTIFY qgsProjectChanged )
+    Q_PROPERTY( QgsProject *qgsProject READ qgsProject WRITE setQgsProject NOTIFY qgsProjectChanged )
     Q_PROPERTY( LayerModelTypes modelType READ modelType WRITE setModelType NOTIFY modelTypeChanged )
-    Q_PROPERTY( LayersModel* model READ model WRITE setModel NOTIFY modelChanged )
+    Q_PROPERTY( LayersModel *model READ model WRITE setModel NOTIFY modelChanged )
 
   public:
-    Q_INVOKABLE explicit LayersProxyModel( QObject *parent = nullptr  );
+    Q_INVOKABLE explicit LayersProxyModel( QObject *parent = nullptr );
 
+    enum LayerModelTypes
+    {
+      AllLayers,
+      ActiveLayerSelection
+    };
     Q_ENUM( LayerModelTypes );
 
     bool filterAcceptsRow( int source_row, const QModelIndex &source_parent ) const override;
@@ -63,6 +62,9 @@ class LayersProxyModel : public QgsMapLayerProxyModel
      */
     QList<QgsMapLayer *> layers() const;
 
+    //! Filter current model according to its type
+    void applyFilterFunction();
+
     //! Getters and setters
 
     QgsProject *qgsProject() const;

app/main.cpp

@@ -349,7 +349,7 @@ void initDeclarative()
   qmlRegisterType< SplittingMapTool >( "mm", 1, 0, "SplittingMapTool" );
   qmlRegisterType< MeasurementMapTool >( "mm", 1, 0, "MeasurementMapTool" );
 
-  //qmlRegisterType<LayerModelTypes>( "mm", 1, 0, "LayerModelTypes" );
+  // layers model
   qmlRegisterType<LayersProxyModel>( "mm", 1, 0, "LayersProxyModel" );
   qmlRegisterType<LayersModel>( "mm", 1, 0, "LayersModel" );
 }