Allow QgsDataProvider access through QgsMapLayer

Avoids having to cast to QgsRasterLayer/QgsVectorLayer before
accessing the common QgsDataProvider members

python/core/qgsmaplayer.sip

@@ -95,6 +95,13 @@ Returns the layer's unique ID, which is used to access this layer from QgsProjec
  :rtype: str
 %End
 
+    virtual QgsDataProvider *dataProvider();
+%Docstring
+ Returns the layer's data provider.
+ :rtype: QgsDataProvider
+%End
+
+
     QString originalName() const;
 %Docstring
  Returns the original name of the layer.

python/core/qgsvectorlayer.sip

@@ -383,12 +383,7 @@ Returns a comment for the data in the layer
  :rtype: str
 %End
 
-    QgsVectorDataProvider *dataProvider();
-%Docstring
-Returns the data provider
- :rtype: QgsVectorDataProvider
-%End
-
+    virtual QgsVectorDataProvider *dataProvider();
 
     void setProviderEncoding( const QString &encoding );
 %Docstring

python/core/raster/qgsrasterlayer.sip

@@ -103,12 +103,12 @@ class QgsRasterLayer : QgsMapLayer
     QString bandName( int bandNoInt ) const;
 
     /** Returns the data provider */
-    QgsRasterDataProvider* dataProvider();
+    virtual QgsRasterDataProvider* dataProvider();
 
     /** Returns the data provider in a const-correct manner
       @note available in python bindings as constDataProvider()
      */
-    const QgsRasterDataProvider* dataProvider() const /PyName=constDataProvider/;
+    virtual const QgsRasterDataProvider* dataProvider() const /PyName=constDataProvider/;
 
     /** Synchronises with changes in the datasource */
     virtual void reload();

src/core/layertree/qgslayertreegroup.h

@@ -215,13 +215,20 @@ class CORE_EXPORT QgsLayerTreeGroup : public QgsLayerTreeNode
 
     //! Whether the group is mutually exclusive (i.e. only one child can be checked at a time)
     bool mMutuallyExclusive;
-    //! Keeps track which child has been most recently selected
-    //! (so if the whole group is unchecked and checked again, we know which child to check)
+
+    /**
+     * Keeps track which child has been most recently selected
+     * (so if the whole group is unchecked and checked again, we know which child to check)
+     */
     int mMutuallyExclusiveChildIndex;
 
   private:
 
 #ifdef SIP_RUN
+
+    /**
+     * Copies are not allowed
+     */
     QgsLayerTreeGroup( const QgsLayerTreeGroup &other );
 #endif
 

src/core/layertree/qgslayertreelayer.cpp

@@ -146,25 +146,7 @@ void QgsLayerTreeLayer::writeXml( QDomElement &parentElement )
   if ( mRef.layer )
   {
     elem.setAttribute( "source", mRef.layer->publicSource() );
-    QString providerKey;
-    switch ( mRef.layer->type() )
-    {
-      case QgsMapLayer::VectorLayer:
-      {
-        QgsVectorLayer *vl = qobject_cast< QgsVectorLayer * >( mRef.layer );
-        providerKey = vl->dataProvider()->name();
-        break;
-      }
-      case QgsMapLayer::RasterLayer:
-      {
-        QgsRasterLayer *rl = qobject_cast< QgsRasterLayer * >( mRef.layer );
-        providerKey = rl->dataProvider()->name();
-        break;
-      }
-      case QgsMapLayer::PluginLayer:
-        break;
-    }
-    elem.setAttribute( "providerKey", providerKey );
+    elem.setAttribute( "providerKey", mRef.layer->dataProvider() ? mRef.layer->dataProvider()->name() : QString() );
   }
 
   elem.setAttribute( QStringLiteral( "checked" ), mChecked ? QStringLiteral( "Qt::Checked" ) : QStringLiteral( "Qt::Unchecked" ) );

src/core/layertree/qgslayertreelayer.h

@@ -131,6 +131,10 @@ class CORE_EXPORT QgsLayerTreeLayer : public QgsLayerTreeNode
   private:
 
 #ifdef SIP_RUN
+
+    /**
+     * Copies are not allowed
+     */
     QgsLayerTreeLayer( const QgsLayerTreeLayer &other );
 #endif
 };

src/core/qgscolorramp.h

@@ -450,7 +450,6 @@ class CORE_EXPORT QgsPresetSchemeColorRamp : public QgsColorRamp, public QgsColo
      */
     QList< QColor > colors() const;
 
-    // QgsColorRamp interface
     virtual double value( int index ) const override;
     virtual QColor color( double value ) const override;
     virtual QString type() const override { return QStringLiteral( "preset" ); }
@@ -459,10 +458,8 @@ class CORE_EXPORT QgsPresetSchemeColorRamp : public QgsColorRamp, public QgsColo
     virtual QgsStringMap properties() const override;
     int count() const override;
 
-    // QgsColorScheme interface
     QString schemeName() const override { return QStringLiteral( "preset" ); }
-    QgsNamedColorList fetchColors( const QString &context = QString(),
-                                   const QColor &baseColor = QColor() ) override;
+    QgsNamedColorList fetchColors( const QString &context = QString(), const QColor &baseColor = QColor() ) override;
     bool isEditable() const override { return true; }
 
   private:

src/core/qgsmaplayer.h

@@ -35,6 +35,7 @@
 #include "qgsrendercontext.h"
 #include "qgsmaplayerdependency.h"
 
+class QgsDataProvider;
 class QgsMapLayerLegend;
 class QgsMapLayerRenderer;
 class QgsMapLayerStyleManager;
@@ -128,6 +129,17 @@ class CORE_EXPORT QgsMapLayer : public QObject
      */
     QString name() const;
 
+    /**
+     * Returns the layer's data provider.
+     */
+    virtual QgsDataProvider *dataProvider() { return nullptr; }
+
+    /**
+     * Returns the layer's data provider in a const-correct manner
+     * \note not available in Python bindings
+     */
+    virtual const QgsDataProvider *dataProvider() const SIP_SKIP { return nullptr; }
+
     /** Returns the original name of the layer.
      * \returns the original layer name
      */

src/core/qgsmaplayerproxymodel.cpp

@@ -98,11 +98,7 @@ bool QgsMapLayerProxyModel::filterAcceptsRow( int source_row, const QModelIndex
   if ( mExceptList.contains( layer ) )
     return false;
 
-  QgsVectorLayer *vl = qobject_cast<QgsVectorLayer *>( layer );
-  if ( vl && mExcludedProviders.contains( vl->dataProvider()->name() ) )
-    return false;
-  QgsRasterLayer *rl = qobject_cast<QgsRasterLayer *>( layer );
-  if ( rl && mExcludedProviders.contains( rl->dataProvider()->name() ) )
+  if ( mExcludedProviders.contains( layer->dataProvider()->name() ) )
     return false;
 
   if ( mFilters.testFlag( WritableLayer ) && layer->readOnly() )
@@ -122,7 +118,7 @@ bool QgsMapLayerProxyModel::filterAcceptsRow( int source_row, const QModelIndex
                         mFilters.testFlag( HasGeometry );
   if ( detectGeometry && layer->type() == QgsMapLayer::VectorLayer )
   {
-    if ( vl )
+    if ( QgsVectorLayer *vl = qobject_cast< QgsVectorLayer *>( layer ) )
     {
       if ( mFilters.testFlag( HasGeometry ) && vl->hasGeometryType() )
         return true;

src/core/qgsmaplayerref.h

@@ -65,26 +65,9 @@ struct _LayerRef
          layer->name() != name )
       return false;
 
-    switch ( layer->type() )
-    {
-      case QgsMapLayer::VectorLayer:
-      {
-        QgsVectorLayer *vl = qobject_cast< QgsVectorLayer * >( layer );
-        if ( vl->dataProvider()->name() != provider )
-          return false;
-        break;
-      }
-      case QgsMapLayer::RasterLayer:
-      {
-        QgsRasterLayer *rl = qobject_cast< QgsRasterLayer * >( layer );
-        if ( rl->dataProvider()->name() != provider )
-          return false;
-        break;
-      }
-      case QgsMapLayer::PluginLayer:
-        break;
+    if ( layer->dataProvider()->name() != provider )
+      return false;
 
-    }
     return true;
   }
 };

src/core/qgsmimedatautils.cpp

@@ -108,23 +108,21 @@ static void _addLayerTreeNodeToUriList( QgsLayerTreeNode *node, QgsMimeDataUtils
   else if ( QgsLayerTree::isLayer( node ) )
   {
     QgsLayerTreeLayer *nodeLayer = QgsLayerTree::toLayer( node );
-    if ( !nodeLayer->layer() )
+    QgsMapLayer *layer = nodeLayer->layer();
+    if ( !layer )
       return;
 
     QgsMimeDataUtils::Uri uri;
-    if ( QgsVectorLayer *vlayer = qobject_cast<QgsVectorLayer *>( nodeLayer->layer() ) )
+    uri.name = layer->name();
+    uri.uri = layer->dataProvider()->dataSourceUri();
+    uri.providerKey = layer->dataProvider()->name();
+    if ( layer->type() == QgsMapLayer::VectorLayer )
     {
       uri.layerType = QStringLiteral( "vector" );
-      uri.name = vlayer->name();
-      uri.providerKey = vlayer->dataProvider()->name();
-      uri.uri = vlayer->dataProvider()->dataSourceUri();
     }
-    else if ( QgsRasterLayer *rlayer = qobject_cast<QgsRasterLayer *>( nodeLayer->layer() ) )
+    else if ( layer->type() == QgsMapLayer::RasterLayer )
     {
       uri.layerType = QStringLiteral( "raster" );
-      uri.name = rlayer->name();
-      uri.providerKey = rlayer->dataProvider()->name();
-      uri.uri = rlayer->dataProvider()->dataSourceUri();
     }
     else
     {

src/core/qgsvectordataprovider.h

@@ -525,14 +525,14 @@ class CORE_EXPORT QgsVectorDataProvider : public QgsDataProvider
      * Get metadata, dependent on the provider type, that will be display in the metadata tab of the layer properties.
      * \returns The provider metadata
      */
-    virtual QVariantMap metadata() const { return QVariantMap(); };
+    virtual QVariantMap metadata() const { return QVariantMap(); }
 
     /**
      * Get the translated metadata key.
      * \param mdKey The metadata key
      * \returns The translated metadata value
      */
-    virtual QString translateMetadataKey( const QString &mdKey ) const { return mdKey; };
+    virtual QString translateMetadataKey( const QString &mdKey ) const { return mdKey; }
 
     /**
      * Get the translated metadata value.
@@ -540,7 +540,7 @@ class CORE_EXPORT QgsVectorDataProvider : public QgsDataProvider
      * \param value The metadata value
      * \returns The translated metadata value
      */
-    virtual QString translateMetadataValue( const QString &mdKey, const QVariant &value ) const { Q_UNUSED( mdKey ); return value.toString(); };
+    virtual QString translateMetadataValue( const QString &mdKey, const QVariant &value ) const { Q_UNUSED( mdKey ); return value.toString(); }
 
   signals:
 

src/core/qgsvectorlayer.h

@@ -33,6 +33,7 @@
 #include "qgsfeaturerequest.h"
 #include "qgsfields.h"
 #include "qgssnapper.h"
+#include "qgsvectordataprovider.h"
 #include "qgsvectorsimplifymethod.h"
 #include "qgseditformconfig.h"
 #include "qgsattributetableconfig.h"
@@ -63,7 +64,6 @@ class QgsRelation;
 class QgsRelationManager;
 class QgsSingleSymbolRenderer;
 class QgsSymbol;
-class QgsVectorDataProvider;
 class QgsVectorLayerJoinInfo;
 class QgsVectorLayerEditBuffer;
 class QgsVectorLayerJoinBuffer;
@@ -437,13 +437,8 @@ class CORE_EXPORT QgsVectorLayer : public QgsMapLayer, public QgsExpressionConte
      */
     QString displayExpression() const;
 
-    //! Returns the data provider
-    QgsVectorDataProvider *dataProvider();
-
-    /** Returns the data provider in a const-correct manner
-     * \note not available in Python bindings
-     */
-    const QgsVectorDataProvider *dataProvider() const SIP_SKIP;
+    QgsVectorDataProvider *dataProvider() override;
+    const QgsVectorDataProvider *dataProvider() const override SIP_SKIP;
 
     //! Sets the textencoding of the data provider
     void setProviderEncoding( const QString &encoding );

src/core/raster/qgsrasterlayer.h

@@ -32,6 +32,7 @@
 #include "qgis.h"
 #include "qgsmaplayer.h"
 #include "qgsraster.h"
+#include "qgsrasterdataprovider.h"
 #include "qgsrasterpipe.h"
 #include "qgsrasterviewport.h"
 #include "qgsrasterminmaxorigin.h"
@@ -247,13 +248,12 @@ class CORE_EXPORT QgsRasterLayer : public QgsMapLayer
     //! \brief Get the name of a band given its number
     QString bandName( int bandNoInt ) const;
 
-    //! Returns the data provider
-    QgsRasterDataProvider *dataProvider();
+    QgsRasterDataProvider *dataProvider() override;
 
     /** Returns the data provider in a const-correct manner
       \note available in Python bindings as constDataProvider()
      */
-    const QgsRasterDataProvider *dataProvider() const;
+    const QgsRasterDataProvider *dataProvider() const override;
 
     //! Synchronises with changes in the datasource
     virtual void reload() override;