API break update + read/write context in labeling and text renderer

This enables correct loading/saving of relative paths of SVG files for background of labels

doc/api_break.dox

@@ -762,6 +762,16 @@ all these item added events.
 - addComposerMap no longer takes a setDefaultPreviewStyle argument.
 - the mapsToRestore parameter has been removed from addItemsFromXml
 
+QgsConditionalLayerStyle      {#qgis_api_break_3_0_QgsConditionalLayerStyle}
+------------------------
+
+- readXml() and writeXml() require a new argument: a reference to QgsReadWriteContext
+
+QgsConditionalStyle      {#qgis_api_break_3_0_QgsConditionalStyle}
+-------------------
+
+- readXml() and writeXml() require a new argument: a reference to QgsReadWriteContext
+
 QgsCoordinateReferenceSystem        {#qgis_api_break_3_0_QgsCoordinateReferenceSystem}
 ----------------------------
 
@@ -921,6 +931,8 @@ QgsDiagramRenderer        {#qgis_api_break_3_0_QgsDiagramRenderer}
 - referencedFields() no longer takes a QgsFields argument.
 - renderDiagram() now takes an optional data defined overrides collection argument.
 - readXml(), _readXml(), writeXml(), _writeXml() do not take QgsVectorLayer as an argument anymore.
+- readXml(), _readXml(), writeXml(), _writeXml() require a new argument: a reference to QgsReadWriteContext
+
 
 
 QgsDiagramLayerSettings        {#qgis_api_break_3_0_QgsDiagramLayerSettings}
@@ -1098,6 +1110,8 @@ QgsFeatureRendererV2        {#qgis_api_break_3_0_QgsFeatureRendererV2}
 - originalSymbolsForFeature( QgsFeature& feat ) has been removed. The originalSymbolsForFeature( QgsFeature& feat, QgsRenderContext& context ) method should be used instead (previously available as originalSymbolsForFeature2 in PyQGIS bindings).
 - copyPaintEffect() was removed. copyRendererData() should be used instead.
 - usedAttributes() now requires a QgsRenderContext argument.
+- save() expects QgsReadWriteContext reference as the last argument
+- static create() method in subclasses expects QgsReadWriteContext reference as the last argument
 
 
 QgsFeatureRequest        {#qgis_api_break_3_0_QgsFeatureRequest}
@@ -1417,6 +1431,9 @@ screenUpdateRequested() were removed. These members have had no effect for a num
 - asLayerDefinition(), fromLayerDefinition(), fromLayerDefinitionFile() were moved to QgsLayerDefinition class and renamed to exportLayerDefinitionLayers() resp. loadLayerDefinitionLayers()
 - loadNamedStyleFromDb() was renamed to loadNamedStyleFromDatabase()
 - readLayerXml() and writeLayerXml() expect QgsReadWriteContext reference as the last argument
+- readSymbology() and writeSymbology() expect QgsReadWriteContext reference as the last argument
+- readStyle() and writeStyle() expect QgsReadWriteContext reference as the last argument
+- readXml() and writeXml() expect QgsReadWriteContext reference as the last argument
 - the invalidTransformInput() slot was removed - calling this slot had no effect
 - metadata() was renamed to htmlMetadata()
 
@@ -1627,6 +1644,7 @@ dataDefinedValue(), dataDefinedEvaluate(), dataDefinedIsActive(),
 dataDefinedUseExpression(), dataDefinedProperties() and dataDefinedNames()
 members were removed. Use the QgsProperty framework through dataDefinedProperties()
 and setDataDefinedProperties() instead.
+- readXml() and writeXml() now expect a reference to QgsReadWriteContext.
 
 
 QgsPanelWidgetStack        {#qgis_api_break_3_0_QgsPanelWidgetStack}
@@ -1944,11 +1962,26 @@ QgsSvgCache        {#qgis_api_break_3_0_QgsSvgCache}
 - This class is no longer a singleton and instance() has been removed. Instead use QgsApplication::svgCache() to access an application-wide cache.
 - containsParamsV2() was removed. Use containsParamsV3() instead.
 - The rasterScaleFactor parameter was removed from all methods
+- svgAsImage(), svgAsPicture(), svgViewboxSize(), svgContent(), insertSvg(), cacheEntry() only accept absolute path to SVG file (relative paths will not be resolved).
 
 QgsSvgCacheEntry       {#qgis_api_break_3_0_QgsSvgCacheEntry}
 ----------------
 
 - The rasterScaleFactor member was removed.
+- The lookupKey member was removed.
+- The "file" member has been renamed to "path".
+- Constructor does not take lookup key as an optional last argument
+
+
+QgsSVGFillSymbolLayer    {#qgis_api_break_3_0_QgsSVGFillSymbolLayer}
+---------------------
+
+- The first argument of the constructor (svgFilePath) does not have default value anymore.
+
+QgsSvgMarkerSymbolLayer    {#qgis_api_break_3_0_QgsSvgMarkerSymbolLayer}
+-----------------------
+
+- The first argument of the constructor (path) does not have a default value anymore.
 
 QgsStyle (renamed from QgsStyleV2)        {#qgis_api_break_3_0_QgsStyle}
 ----------------------------------
@@ -2025,6 +2058,8 @@ QgsSymbolLayerUtils (renamed from QgsSymbolLayerUtilsV2)        {#qgis_api_break
 - pixelSizeScaleFactor() was removed. Use QgsRenderContext::convertToPainterUnits() instead.
 - mapUnitScaleFactor() was removed. Use QgsRenderContext::convertToMapUnits() instead.
 - estimateMaxSymbolBleed() now requires a QgsRenderContext argument (since the bleed depends on render context for non-pixel units)
+- loadSymbol(), saveSymbol(), loadSymbols(), saveSymbols(), loadSymbolLayer() now require a reference to QgsReadWriteContext
+- symbolNameToPath() and symbolPathToName() have been renamed to svgSymbolNameToPath() and svgSymbolPathToName() and they require reference to QgsPathResolver
 
 
 QgsSymbolSelectorWidget        {#qgis_api_break_3_0_QgsSymbolSelectorWidget}
@@ -2254,6 +2289,11 @@ optional property map passing down layer level properties to the SLD encoders. I
 - setScaleMethodToSymbol was removed. This is now handled using data defined scaling at a symbol layer level
 - usedAttributes is now a const method and returns QSet<QString> instead of QStringList
 
+QgsRendererAbstractMetadata   {#qgis_api_break_3_0_QgsRendererAbstractMetadata}
+---------------------------
+
+- createRenderer() now expects a reference to QgsReadWriteContext as the second argument
+
 
 Processing        {#qgis_api_break_3_0_Processing}
 ----------

python/core/qgspallabeling.sip

@@ -426,12 +426,12 @@ class QgsPalLayerSettings
     /** Read settings from a DOM element
      * @note added in 2.12
      */
-    void readXml( QDomElement &elem );
+    void readXml( QDomElement& elem, const QgsReadWriteContext &context );
 
     /** Write settings into a DOM element
      * @note added in 2.12
      */
-    QDomElement writeXml( QDomDocument &doc );
+    QDomElement writeXml( QDomDocument& doc, const QgsReadWriteContext &context );
 
     QgsPropertyCollection &dataDefinedProperties();
 

python/core/qgstextrenderer.sip

@@ -304,7 +304,7 @@ class QgsTextBackgroundSettings
 
     QString svgFile() const;
 %Docstring
- Returns the path to the background SVG file, if set.
+ Returns the absolute path to the background SVG file, if set.
 .. seealso:: setSvgFile()
  :rtype: str
 %End
@@ -312,8 +312,8 @@ class QgsTextBackgroundSettings
     void setSvgFile( const QString &file );
 %Docstring
  Sets the path to the background SVG file. This is only used if type() is set to
- QgsTextBackgroundSettings.ShapeSVG.
- \param file SVG file path
+ QgsTextBackgroundSettings.ShapeSVG. The path must be absolute.
+ \param file Absolute SVG file path
 .. seealso:: svgFile()
 %End
 
@@ -688,13 +688,13 @@ class QgsTextBackgroundSettings
 .. seealso:: readFromLayer()
 %End
 
-    void readXml( const QDomElement &elem );
+    void readXml( const QDomElement &elem, const QgsReadWriteContext &context );
 %Docstring
  Read settings from a DOM element.
 .. seealso:: writeXml()
 %End
 
-    QDomElement writeXml( QDomDocument &doc ) const;
+    QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context ) const;
 %Docstring
  Write settings into a DOM element.
 .. seealso:: readXml()
@@ -1251,13 +1251,13 @@ class QgsTextFormat
 .. seealso:: readFromLayer()
 %End
 
-    void readXml( const QDomElement &elem );
+    void readXml( const QDomElement &elem, const QgsReadWriteContext &context );
 %Docstring
  Read settings from a DOM element.
 .. seealso:: writeXml()
 %End
 
-    QDomElement writeXml( QDomDocument &doc ) const;
+    QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context ) const;
 %Docstring
  Write settings into a DOM element.
 .. seealso:: readXml()

src/app/qgslabelingwidget.cpp

@@ -20,6 +20,7 @@
 
 #include "qgslabelengineconfigdialog.h"
 #include "qgslabelinggui.h"
+#include "qgsreadwritecontext.h"
 #include "qgsrulebasedlabelingwidget.h"
 #include "qgsvectorlayer.h"
 #include "qgsvectorlayerlabeling.h"
@@ -75,8 +76,8 @@ void QgsLabelingWidget::setLayer( QgsMapLayer *mapLayer )
   if ( mLayer->labeling() )
   {
     QDomDocument doc;
-    QDomElement oldSettings = mLayer->labeling()->save( doc );
-    mOldSettings.reset( QgsAbstractVectorLayerLabeling::create( oldSettings ) );
+    QDomElement oldSettings = mLayer->labeling()->save( doc, QgsReadWriteContext() );
+    mOldSettings.reset( QgsAbstractVectorLayerLabeling::create( oldSettings, QgsReadWriteContext() ) );
     mOldPalSettings.readFromLayer( mLayer );
   }
   else

src/app/qgsrulebasedlabelingwidget.cpp

@@ -20,6 +20,7 @@
 #include "qgslabelinggui.h"
 #include "qgsmapcanvas.h"
 #include "qgsproject.h"
+#include "qgsreadwritecontext.h"
 #include "qgsrulebasedlabeling.h"
 #include "qgsvectorlayer.h"
 #include "qgsvectorlayerlabeling.h"
@@ -479,7 +480,7 @@ QMimeData *QgsRuleBasedLabelingModel::mimeData( const QModelIndexList &indexes )
 
     QDomElement rootElem = doc.createElement( QStringLiteral( "rule_mime" ) );
     rootElem.setAttribute( QStringLiteral( "type" ), QStringLiteral( "labeling" ) ); // for determining whether rules are from renderer or labeling
-    QDomElement rulesElem = rule->save( doc );
+    QDomElement rulesElem = rule->save( doc, QgsReadWriteContext() );
     rootElem.appendChild( rulesElem );
     doc.appendChild( rootElem );
 
@@ -529,7 +530,7 @@ bool QgsRuleBasedLabelingModel::dropMimeData( const QMimeData *data, Qt::DropAct
     QDomElement ruleElem = rootElem.firstChildElement( QStringLiteral( "rule" ) );
     if ( rootElem.attribute( QStringLiteral( "type" ) ) == QLatin1String( "renderer" ) )
       _renderer2labelingRules( ruleElem ); // do some modifications so that we load the rules more nicely
-    QgsRuleBasedLabeling::Rule *rule = QgsRuleBasedLabeling::Rule::create( ruleElem );
+    QgsRuleBasedLabeling::Rule *rule = QgsRuleBasedLabeling::Rule::create( ruleElem, QgsReadWriteContext() );
 
     insertRule( parent, row + rows, rule );
 

src/core/qgspallabeling.cpp

@@ -768,7 +768,7 @@ void QgsPalLayerSettings::writeToLayer( QgsVectorLayer *layer )
   layer->emitStyleChanged();
 }
 
-void QgsPalLayerSettings::readXml( QDomElement &elem )
+void QgsPalLayerSettings::readXml( QDomElement &elem, const QgsReadWriteContext &context )
 {
   enabled = true;
   drawLabels = true;
@@ -778,7 +778,7 @@ void QgsPalLayerSettings::readXml( QDomElement &elem )
   fieldName = textStyleElem.attribute( QStringLiteral( "fieldName" ) );
   isExpression = textStyleElem.attribute( QStringLiteral( "isExpression" ) ).toInt();
 
-  mFormat.readXml( elem );
+  mFormat.readXml( elem, context );
   previewBkgrdColor = QColor( textStyleElem.attribute( QStringLiteral( "previewBkgrdColor" ), QStringLiteral( "#ffffff" ) ) );
   substitutions.readXml( textStyleElem.firstChildElement( QStringLiteral( "substitutions" ) ) );
   useSubstitutions = textStyleElem.attribute( QStringLiteral( "useSubstitutions" ) ).toInt();
@@ -889,11 +889,11 @@ void QgsPalLayerSettings::readXml( QDomElement &elem )
 
 
 
-QDomElement QgsPalLayerSettings::writeXml( QDomDocument &doc )
+QDomElement QgsPalLayerSettings::writeXml( QDomDocument &doc, const QgsReadWriteContext &context )
 {
   // we assume (enabled == true && drawLabels == true) so those are not saved
 
-  QDomElement textStyleElem = mFormat.writeXml( doc );
+  QDomElement textStyleElem = mFormat.writeXml( doc, context );
 
   // text style
   textStyleElem.setAttribute( QStringLiteral( "fieldName" ), fieldName );

src/core/qgspallabeling.h

@@ -531,12 +531,12 @@ class CORE_EXPORT QgsPalLayerSettings
     /** Read settings from a DOM element
      * \since QGIS 2.12
      */
-    void readXml( QDomElement &elem );
+    void readXml( QDomElement &elem, const QgsReadWriteContext &context );
 
     /** Write settings into a DOM element
      * \since QGIS 2.12
      */
-    QDomElement writeXml( QDomDocument &doc );
+    QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context );
 
     /** Returns a reference to the label's property collection, used for data defined overrides.
      * \since QGIS 3.0

src/core/qgsrulebasedlabeling.cpp

@@ -193,14 +193,14 @@ QgsRuleBasedLabeling::Rule *QgsRuleBasedLabeling::Rule::clone() const
   return newrule;
 }
 
-QgsRuleBasedLabeling::Rule *QgsRuleBasedLabeling::Rule::create( const QDomElement &ruleElem )
+QgsRuleBasedLabeling::Rule *QgsRuleBasedLabeling::Rule::create( const QDomElement &ruleElem, const QgsReadWriteContext &context )
 {
   QgsPalLayerSettings *settings = nullptr;
   QDomElement settingsElem = ruleElem.firstChildElement( QStringLiteral( "settings" ) );
   if ( !settingsElem.isNull() )
   {
     settings = new QgsPalLayerSettings;
-    settings->readXml( settingsElem );
+    settings->readXml( settingsElem, context );
   }
 
   QString filterExp = ruleElem.attribute( QStringLiteral( "filter" ) );
@@ -218,7 +218,7 @@ QgsRuleBasedLabeling::Rule *QgsRuleBasedLabeling::Rule::create( const QDomElemen
   QDomElement childRuleElem = ruleElem.firstChildElement( QStringLiteral( "rule" ) );
   while ( !childRuleElem.isNull() )
   {
-    Rule *childRule = create( childRuleElem );
+    Rule *childRule = create( childRuleElem, context );
     if ( childRule )
     {
       rule->appendChild( childRule );
@@ -233,13 +233,13 @@ QgsRuleBasedLabeling::Rule *QgsRuleBasedLabeling::Rule::create( const QDomElemen
   return rule;
 }
 
-QDomElement QgsRuleBasedLabeling::Rule::save( QDomDocument &doc ) const
+QDomElement QgsRuleBasedLabeling::Rule::save( QDomDocument &doc, const QgsReadWriteContext &context ) const
 {
   QDomElement ruleElem = doc.createElement( QStringLiteral( "rule" ) );
 
   if ( mSettings )
   {
-    ruleElem.appendChild( mSettings->writeXml( doc ) );
+    ruleElem.appendChild( mSettings->writeXml( doc, context ) );
   }
   if ( !mFilterExp.isEmpty() )
     ruleElem.setAttribute( QStringLiteral( "filter" ), mFilterExp );
@@ -256,7 +256,7 @@ QDomElement QgsRuleBasedLabeling::Rule::save( QDomDocument &doc ) const
   for ( RuleList::const_iterator it = mChildren.constBegin(); it != mChildren.constEnd(); ++it )
   {
     Rule *rule = *it;
-    ruleElem.appendChild( rule->save( doc ) );
+    ruleElem.appendChild( rule->save( doc, context ) );
   }
   return ruleElem;
 }
@@ -401,11 +401,11 @@ QgsRuleBasedLabeling::~QgsRuleBasedLabeling()
 }
 
 
-QgsRuleBasedLabeling *QgsRuleBasedLabeling::create( const QDomElement &element )
+QgsRuleBasedLabeling *QgsRuleBasedLabeling::create( const QDomElement &element, const QgsReadWriteContext &context )
 {
   QDomElement rulesElem = element.firstChildElement( QStringLiteral( "rules" ) );
 
-  Rule *root = Rule::create( rulesElem );
+  Rule *root = Rule::create( rulesElem, context );
   if ( !root )
     return nullptr;
 
@@ -418,12 +418,12 @@ QString QgsRuleBasedLabeling::type() const
   return QStringLiteral( "rule-based" );
 }
 
-QDomElement QgsRuleBasedLabeling::save( QDomDocument &doc ) const
+QDomElement QgsRuleBasedLabeling::save( QDomDocument &doc, const QgsReadWriteContext &context ) const
 {
   QDomElement elem = doc.createElement( QStringLiteral( "labeling" ) );
   elem.setAttribute( QStringLiteral( "type" ), QStringLiteral( "rule-based" ) );
 
-  QDomElement rulesElem = mRootRule->save( doc );
+  QDomElement rulesElem = mRootRule->save( doc, context );
   rulesElem.setTagName( QStringLiteral( "rules" ) ); // instead of just "rule"
   elem.appendChild( rulesElem );
 

src/core/qgsrulebasedlabeling.h

@@ -241,10 +241,10 @@ class CORE_EXPORT QgsRuleBasedLabeling : public QgsAbstractVectorLayerLabeling
          * \param ruleElem  The XML rule element
          * \returns A new rule
          */
-        static Rule *create( const QDomElement &ruleElem );
+        static Rule *create( const QDomElement &ruleElem, const QgsReadWriteContext &context );
 
         //! store labeling info to XML element
-        QDomElement save( QDomDocument &doc ) const;
+        QDomElement save( QDomDocument &doc, const QgsReadWriteContext &context ) const;
 
         // evaluation
 
@@ -323,12 +323,12 @@ class CORE_EXPORT QgsRuleBasedLabeling : public QgsAbstractVectorLayerLabeling
     const Rule *rootRule() const { return mRootRule; }
 
     //! Create the instance from a DOM element with saved configuration
-    static QgsRuleBasedLabeling *create( const QDomElement &element );
+    static QgsRuleBasedLabeling *create( const QDomElement &element, const QgsReadWriteContext &context );
 
     // implementation of parent interface
 
     virtual QString type() const override;
-    virtual QDomElement save( QDomDocument &doc ) const override;
+    virtual QDomElement save( QDomDocument &doc, const QgsReadWriteContext &context ) const override;
     virtual QgsVectorLayerLabelProvider *provider( QgsVectorLayer *layer ) const override;
     virtual QStringList subProviders() const override;
     virtual QgsPalLayerSettings settings( QgsVectorLayer *layer, const QString &providerId = QString() ) const override;

src/core/qgstextrenderer.cpp

@@ -18,6 +18,8 @@
 #include "qgis.h"
 #include "qgstextrenderer_p.h"
 #include "qgsfontutils.h"
+#include "qgspathresolver.h"
+#include "qgsreadwritecontext.h"
 #include "qgsvectorlayer.h"
 #include "qgssymbollayerutils.h"
 #include "qgspainting.h"
@@ -805,14 +807,12 @@ void QgsTextBackgroundSettings::writeToLayer( QgsVectorLayer *layer ) const
   }
 }
 
-void QgsTextBackgroundSettings::readXml( const QDomElement &elem )
+void QgsTextBackgroundSettings::readXml( const QDomElement &elem, const QgsReadWriteContext &context )
 {
-  // TODO: convert relative path to absolute
-
   QDomElement backgroundElem = elem.firstChildElement( QStringLiteral( "background" ) );
   d->enabled = backgroundElem.attribute( QStringLiteral( "shapeDraw" ), QStringLiteral( "0" ) ).toInt();
   d->type = static_cast< ShapeType >( backgroundElem.attribute( QStringLiteral( "shapeType" ), QString::number( ShapeRectangle ) ).toUInt() );
-  d->svgFile = backgroundElem.attribute( QStringLiteral( "shapeSVGFile" ) );
+  d->svgFile = QgsSymbolLayerUtils::svgSymbolNameToPath( backgroundElem.attribute( QStringLiteral( "shapeSVGFile" ) ), context.pathResolver() );
   d->sizeType = static_cast< SizeType >( backgroundElem.attribute( QStringLiteral( "shapeSizeType" ), QString::number( SizeBuffer ) ).toUInt() );
   d->size = QSizeF( backgroundElem.attribute( QStringLiteral( "shapeSizeX" ), QStringLiteral( "0" ) ).toDouble(),
                     backgroundElem.attribute( QStringLiteral( "shapeSizeY" ), QStringLiteral( "0" ) ).toDouble() );
@@ -924,14 +924,12 @@ void QgsTextBackgroundSettings::readXml( const QDomElement &elem )
     setPaintEffect( nullptr );
 }
 
-QDomElement QgsTextBackgroundSettings::writeXml( QDomDocument &doc ) const
+QDomElement QgsTextBackgroundSettings::writeXml( QDomDocument &doc, const QgsReadWriteContext &context ) const
 {
-  // TODO: convert absolute path to relative
-
   QDomElement backgroundElem = doc.createElement( QStringLiteral( "background" ) );
   backgroundElem.setAttribute( QStringLiteral( "shapeDraw" ), d->enabled );
   backgroundElem.setAttribute( QStringLiteral( "shapeType" ), static_cast< unsigned int >( d->type ) );
-  backgroundElem.setAttribute( QStringLiteral( "shapeSVGFile" ), d->svgFile );
+  backgroundElem.setAttribute( QStringLiteral( "shapeSVGFile" ), QgsSymbolLayerUtils::svgSymbolPathToName( d->svgFile, context.pathResolver() ) );
   backgroundElem.setAttribute( QStringLiteral( "shapeSizeType" ), static_cast< unsigned int >( d->sizeType ) );
   backgroundElem.setAttribute( QStringLiteral( "shapeSizeX" ), d->size.width() );
   backgroundElem.setAttribute( QStringLiteral( "shapeSizeY" ), d->size.height() );
@@ -1549,7 +1547,7 @@ void QgsTextFormat::writeToLayer( QgsVectorLayer *layer ) const
   mBackgroundSettings.writeToLayer( layer );
 }
 
-void QgsTextFormat::readXml( const QDomElement &elem )
+void QgsTextFormat::readXml( const QDomElement &elem, const QgsReadWriteContext &context )
 {
   QDomElement textStyleElem = elem.firstChildElement( QStringLiteral( "text-style" ) );
   QFont appFont = QApplication::font();
@@ -1651,15 +1649,15 @@ void QgsTextFormat::readXml( const QDomElement &elem )
   }
   if ( textStyleElem.firstChildElement( QStringLiteral( "background" ) ).isNull() )
   {
-    mBackgroundSettings.readXml( elem );
+    mBackgroundSettings.readXml( elem, context );
   }
   else
   {
-    mBackgroundSettings.readXml( textStyleElem );
+    mBackgroundSettings.readXml( textStyleElem, context );
   }
 }
 
-QDomElement QgsTextFormat::writeXml( QDomDocument &doc ) const
+QDomElement QgsTextFormat::writeXml( QDomDocument &doc, const QgsReadWriteContext &context ) const
 {
   // text style
   QDomElement textStyleElem = doc.createElement( QStringLiteral( "text-style" ) );
@@ -1681,7 +1679,7 @@ QDomElement QgsTextFormat::writeXml( QDomDocument &doc ) const
   textStyleElem.setAttribute( QStringLiteral( "multilineHeight" ), d->multilineHeight );
 
   textStyleElem.appendChild( mBufferSettings.writeXml( doc ) );
-  textStyleElem.appendChild( mBackgroundSettings.writeXml( doc ) );
+  textStyleElem.appendChild( mBackgroundSettings.writeXml( doc, context ) );
   textStyleElem.appendChild( mShadowSettings.writeXml( doc ) );
   return textStyleElem;
 }

src/core/qgstextrenderer.h

@@ -27,6 +27,7 @@
 #include <QPicture>
 #include <QDomElement>
 
+class QgsReadWriteContext;
 class QgsTextBufferSettingsPrivate;
 class QgsTextBackgroundSettingsPrivate;
 class QgsTextShadowSettingsPrivate;
@@ -284,14 +285,14 @@ class CORE_EXPORT QgsTextBackgroundSettings
      */
     void setType( ShapeType type );
 
-    /** Returns the path to the background SVG file, if set.
+    /** Returns the absolute path to the background SVG file, if set.
      * \see setSvgFile()
      */
     QString svgFile() const;
 
     /** Sets the path to the background SVG file. This is only used if type() is set to
-     * QgsTextBackgroundSettings::ShapeSVG.
-     * \param file SVG file path
+     * QgsTextBackgroundSettings::ShapeSVG. The path must be absolute.
+     * \param file Absolute SVG file path
      * \see svgFile()
      */
     void setSvgFile( const QString &file );
@@ -605,12 +606,12 @@ class CORE_EXPORT QgsTextBackgroundSettings
     /** Read settings from a DOM element.
      * \see writeXml()
      */
-    void readXml( const QDomElement &elem );
+    void readXml( const QDomElement &elem, const QgsReadWriteContext &context );
 
     /** Write settings into a DOM element.
      * \see readXml()
      */
-    QDomElement writeXml( QDomDocument &doc ) const;
+    QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context ) const;
 
   private:
 
@@ -1087,12 +1088,12 @@ class CORE_EXPORT QgsTextFormat
     /** Read settings from a DOM element.
      * \see writeXml()
      */
-    void readXml( const QDomElement &elem );
+    void readXml( const QDomElement &elem, const QgsReadWriteContext &context );
 
     /** Write settings into a DOM element.
      * \see readXml()
      */
-    QDomElement writeXml( QDomDocument &doc ) const;
+    QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context ) const;
 
     /** Returns true if any component of the font format requires advanced effects
      * such as blend modes, which require output in raster formats to be fully respected.

src/core/qgstextrenderer_p.h

@@ -151,7 +151,7 @@ class CORE_EXPORT QgsTextBackgroundSettingsPrivate : public QSharedData
 
     bool enabled;
     QgsTextBackgroundSettings::ShapeType type;
-    QString svgFile;
+    QString svgFile;   //!< Absolute path to SVG file
     QgsTextBackgroundSettings::SizeType sizeType;
     QSizeF size;
     QgsUnitTypes::RenderUnit sizeUnits;

src/core/qgsvectorlayer.cpp

@@ -1782,7 +1782,7 @@ bool QgsVectorLayer::readStyle( const QDomNode &node, QString &errorMessage, con
     QDomElement labelingElement = node.firstChildElement( QStringLiteral( "labeling" ) );
     if ( !labelingElement.isNull() )
     {
-      QgsAbstractVectorLayerLabeling *l = QgsAbstractVectorLayerLabeling::create( labelingElement );
+      QgsAbstractVectorLayerLabeling *l = QgsAbstractVectorLayerLabeling::create( labelingElement, context );
       setLabeling( l ? l : new QgsVectorLayerSimpleLabeling );
     }
 
@@ -2011,7 +2011,7 @@ bool QgsVectorLayer::writeStyle( QDomNode &node, QDomDocument &doc, QString &err
 
     if ( mLabeling )
     {
-      QDomElement labelingElement = mLabeling->save( doc );
+      QDomElement labelingElement = mLabeling->save( doc, context );
       node.appendChild( labelingElement );
     }
 

src/core/qgsvectorlayerlabeling.cpp

@@ -19,11 +19,11 @@
 #include "qgsvectorlayer.h"
 
 
-QgsAbstractVectorLayerLabeling *QgsAbstractVectorLayerLabeling::create( const QDomElement &element )
+QgsAbstractVectorLayerLabeling *QgsAbstractVectorLayerLabeling::create( const QDomElement &element, const QgsReadWriteContext &context )
 {
   if ( element.attribute( QStringLiteral( "type" ) ) == QLatin1String( "rule-based" ) )
   {
-    return QgsRuleBasedLabeling::create( element );
+    return QgsRuleBasedLabeling::create( element, context );
   }
   else
   {
@@ -45,8 +45,9 @@ QString QgsVectorLayerSimpleLabeling::type() const
   return QStringLiteral( "simple" );
 }
 
-QDomElement QgsVectorLayerSimpleLabeling::save( QDomDocument &doc ) const
+QDomElement QgsVectorLayerSimpleLabeling::save( QDomDocument &doc, const QgsReadWriteContext &context ) const
 {
+  Q_UNUSED( context );
   // all configuration is kept in layer custom properties (for compatibility)
   QDomElement elem = doc.createElement( QStringLiteral( "labeling" ) );
   elem.setAttribute( QStringLiteral( "type" ), QStringLiteral( "simple" ) );

src/core/qgsvectorlayerlabeling.h

@@ -24,6 +24,7 @@ class QDomDocument;
 class QDomElement;
 
 class QgsPalLayerSettings;
+class QgsReadWriteContext;
 class QgsVectorLayer;
 class QgsVectorLayerLabelProvider;
 
@@ -47,7 +48,7 @@ class CORE_EXPORT QgsAbstractVectorLayerLabeling
     virtual QgsVectorLayerLabelProvider *provider( QgsVectorLayer *layer ) const = 0;
 
     //! Return labeling configuration as XML element
-    virtual QDomElement save( QDomDocument &doc ) const = 0;
+    virtual QDomElement save( QDomDocument &doc, const QgsReadWriteContext &context ) const = 0;
 
     //! Get list of sub-providers within the layer's labeling.
     virtual QStringList subProviders() const { return QStringList( QString() ); }
@@ -67,7 +68,7 @@ class CORE_EXPORT QgsAbstractVectorLayerLabeling
     // static stuff
 
     //! Try to create instance of an implementation based on the XML data
-    static QgsAbstractVectorLayerLabeling *create( const QDomElement &element );
+    static QgsAbstractVectorLayerLabeling *create( const QDomElement &element, const QgsReadWriteContext &context );
 };
 
 /** \ingroup core
@@ -85,7 +86,7 @@ class CORE_EXPORT QgsVectorLayerSimpleLabeling : public QgsAbstractVectorLayerLa
 
     virtual QString type() const override;
     virtual QgsVectorLayerLabelProvider *provider( QgsVectorLayer *layer ) const override;
-    virtual QDomElement save( QDomDocument &doc ) const override;
+    virtual QDomElement save( QDomDocument &doc, const QgsReadWriteContext &context ) const override;
     virtual QgsPalLayerSettings settings( QgsVectorLayer *layer, const QString &providerId = QString() ) const override;
     bool requiresAdvancedEffects( QgsVectorLayer *layer ) const override;
 };

tests/src/core/testqgslabelingengine.cpp

@@ -19,6 +19,7 @@
 #include <qgslabelingengine.h>
 #include <qgsproject.h>
 #include <qgsmaprenderersequentialjob.h>
+#include <qgsreadwritecontext.h>
 #include <qgsrulebasedlabeling.h>
 #include <qgsvectorlayer.h>
 #include <qgsvectorlayerdiagramprovider.h>
@@ -254,15 +255,15 @@ void TestQgsLabelingEngine::testRuleBased()
 
   // test read/write rules
   QDomDocument doc, doc2, doc3;
-  QDomElement e = vl->labeling()->save( doc );
+  QDomElement e = vl->labeling()->save( doc, QgsReadWriteContext() );
   doc.appendChild( e );
   // read saved rules
   doc2.setContent( doc.toString() );
   QDomElement e2 = doc2.documentElement();
-  QgsRuleBasedLabeling *rl2 = QgsRuleBasedLabeling::create( e2 );
+  QgsRuleBasedLabeling *rl2 = QgsRuleBasedLabeling::create( e2, QgsReadWriteContext() );
   QVERIFY( rl2 );
   // check that another save will keep the data the same
-  QDomElement e3 = rl2->save( doc3 );
+  QDomElement e3 = rl2->save( doc3, QgsReadWriteContext() );
   doc3.appendChild( e3 );
   QCOMPARE( doc.toString(), doc3.toString() );