Add convenience method to directly convert QgsProviderSublayerDetails

object to a QgsMapLayer

python/core/auto_generated/providers/qgsprovidersublayerdetails.sip.in

@@ -73,6 +73,24 @@ Returns the layer's URI.
 Sets the layer's ``uri``.
 
 .. seealso:: :py:func:`uri`
+%End
+
+    struct LayerOptions
+    {
+
+      explicit LayerOptions( const QgsCoordinateTransformContext &transformContext );
+%Docstring
+Constructor for LayerOptions with ``transformContext``.
+%End
+
+      QgsCoordinateTransformContext transformContext;
+    };
+
+    QgsMapLayer *toLayer( const LayerOptions &options ) const /Factory/;
+%Docstring
+Creates a new :py:class:`QgsMapLayer` object associated with the sublayer.
+
+Caller takes ownership of the returned layer.
 %End
 
     QString name() const;

src/core/CMakeLists.txt

@@ -215,6 +215,7 @@ set(QGIS_CORE_SRCS
   providers/qgsdataprovider.cpp
   providers/qgsprovidermetadata.cpp
   providers/qgsproviderregistry.cpp
+  providers/qgsprovidersublayerdetails.cpp
 
   providers/arcgis/qgsarcgisportalutils.cpp
   providers/arcgis/qgsarcgisrestquery.cpp

src/core/providers/qgsprovidersublayerdetails.cpp

@@ -0,0 +1,27 @@
+/***************************************************************************
+                             qgsprovidersublayerdetails.cpp
+                             ----------------------------
+    begin                : May 2021
+    copyright            : (C) 2021 by Nyall Dawson
+    email                : nyall dot dawson at gmail dot com
+ ***************************************************************************/
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgsprovidersublayerdetails.h"
+#include "qgsmaplayerfactory.h"
+
+QgsProviderSublayerDetails::LayerOptions::LayerOptions( const QgsCoordinateTransformContext &transformContext )
+  : transformContext( transformContext )
+{}
+
+QgsMapLayer *QgsProviderSublayerDetails::toLayer( const LayerOptions &options ) const
+{
+  return QgsMapLayerFactory::createLayer( mUri, mName, mType, mProviderKey, options.transformContext );
+}

src/core/providers/qgsprovidersublayerdetails.h

@@ -19,6 +19,7 @@
 #include "qgis_core.h"
 #include "qgis.h"
 #include "qgswkbtypes.h"
+#include "qgscoordinatetransformcontext.h"
 
 #include <QString>
 #include <QStringList>
@@ -86,6 +87,27 @@ class CORE_EXPORT QgsProviderSublayerDetails
      */
     void setUri( const QString &uri ) { mUri = uri; }
 
+    /**
+     * Setting options for loading layers.
+     */
+    struct LayerOptions
+    {
+
+      /**
+       * Constructor for LayerOptions with \a transformContext.
+       */
+      explicit LayerOptions( const QgsCoordinateTransformContext &transformContext );
+
+      QgsCoordinateTransformContext transformContext;
+    };
+
+    /**
+     * Creates a new QgsMapLayer object associated with the sublayer.
+     *
+     * Caller takes ownership of the returned layer.
+     */
+    QgsMapLayer *toLayer( const LayerOptions &options ) const SIP_FACTORY;
+
     /**
      * Returns the layer's name.
      *

tests/src/python/test_qgsprovidersublayerdetails.py

@@ -11,15 +11,19 @@ __date__ = '16/03/2020'
 __copyright__ = 'Copyright 2020, The QGIS Project'
 
 import qgis  # NOQA
+import os
 
 from qgis.core import (
     QgsProviderRegistry,
     QgsMapLayerType,
     QgsWkbTypes,
     QgsProviderSublayerDetails,
-    Qgis
+    Qgis,
+    QgsCoordinateTransformContext,
+    QgsVectorLayer
 )
 from qgis.testing import start_app, unittest
+from utilities import unitTestDataPath
 
 # Convenience instances in case you may need them
 # to find the srs.db
@@ -65,6 +69,22 @@ class TestQgsProviderSublayerDetails(unittest.TestCase):
         d.setLayerNumber(13)
         self.assertEqual(d.layerNumber(), 13)
 
+    def test_to_layer(self):
+        """
+        Test converting sub layer details to a layer
+        """
+        details = QgsProviderSublayerDetails()
+        details.setUri(os.path.join(unitTestDataPath(), 'lines.shp'))
+        details.setName('my sub layer')
+        details.setType(QgsMapLayerType.VectorLayer)
+        details.setProviderKey('ogr')
+
+        options = QgsProviderSublayerDetails.LayerOptions(QgsCoordinateTransformContext())
+        ml = details.toLayer(options)
+        self.assertTrue(ml.isValid())
+        self.assertIsInstance(ml, QgsVectorLayer)
+        self.assertEqual(ml.name(), 'my sub layer')
+
 
 if __name__ == '__main__':
     unittest.main()