symbology-ng: updates to symbol layer registry and renderer registry …

…so that they can be used from python.

Added wrappers for these two registries and their metadata classes.


git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@12769 c8812cc2-4d05-0410-92ff-de0c093fc19c

python/core/symbology-ng-core.sip

@@ -3,6 +3,15 @@ typedef QList<QgsSymbolV2*> QgsSymbolV2List;
 
 typedef QList< QPair<QString, QPixmap> > QgsLegendSymbologyList;
 
+
+// this is a workaround for an error in generated code by SIP
+// to ensure it will recognize the class name
+%ModuleHeaderCode
+class QgsRendererV2Widget;
+class QgsSymbolLayerV2Widget;
+%End
+
+
 ///////////////
 
 /*
@@ -608,31 +617,25 @@ typedef QMap<QString, QString> QgsStringMap;
 
 //////////
 
-//typedef QgsSymbolLayerV2 * ( * QgsSymbolLayerV2CreateFunc )( const QgsStringMap& );
-//typedef QgsSymbolLayerV2Widget*( *QgsSymbolLayerV2WidgetFunc )();
+class QgsSymbolLayerV2Widget /External/;
 
-
-class QgsSymbolLayerV2Metadata
+class QgsSymbolLayerV2AbstractMetadata
 {
 %TypeHeaderCode
 #include <qgssymbollayerv2registry.h>
 %End
 
-public:
-  /** construct invalid metadata */
-  QgsSymbolLayerV2Metadata();
-
-  /** construct metadata */
-  // TODO
-  //QgsSymbolLayerV2Metadata(QString name, QgsSymbolV2::SymbolType type,
-  //                         QgsSymbolLayerV2CreateFunc pfCreate,
-  //                         QgsSymbolLayerV2WidgetFunc pfWidget);
+  public:
+    /** construct metadata */
+    QgsSymbolLayerV2AbstractMetadata( QString name, QgsSymbolV2::SymbolType type );
 
-  QString name() const;
-  QgsSymbolV2::SymbolType type();
-  // TODO QgsSymbolLayerV2CreateFunc createFunction() const;
-  // TODO QgsSymbolLayerV2WidgetFunc widgetFunction() const;
+    QString name() const;
+    QgsSymbolV2::SymbolType type() const;
 
+    /** create a symbol layer of this type given the map of properties. */
+    virtual QgsSymbolLayerV2* createSymbolLayer( const QgsStringMap& map ) = 0 /Factory/;
+    /** create widget for symbol layer of this type. Can return NULL if there's no GUI */
+    virtual QgsSymbolLayerV2Widget* createSymbolLayerWidget() /Factory/;
 };
 
 //////////
@@ -649,13 +652,16 @@ public:
   static QgsSymbolLayerV2Registry* instance();
 
   //! return metadata for specified symbol layer
-  QgsSymbolLayerV2Metadata symbolLayerMetadata(QString name) const;
+  QgsSymbolLayerV2AbstractMetadata* symbolLayerMetadata(QString name) const;
 
   //! register a new symbol layer type
-  void addSymbolLayerType(const QgsSymbolLayerV2Metadata& metadata);
+  void addSymbolLayerType(QgsSymbolLayerV2AbstractMetadata* metadata /Transfer/);
 
   //! create a new instance of symbol layer given symbol layer name and properties
-  QgsSymbolLayerV2* createSymbolLayer(QString name, const QgsStringMap& properties) const /Factory/;
+  // TODO: disabled in PyQGIS because if used with symbol layer from Python
+  //   the combination of /Factory/ annotation QgsSymbolLayerV2AbstractMetadata::createSymbolLayer()
+  //   and here is deadly: results in premature deallocation of the symbol layer -> segfaults
+  //QgsSymbolLayerV2* createSymbolLayer(QString name, const QgsStringMap& properties) const /Factory/;
 
   //! return a list of available symbol layers for a specified symbol type
   QStringList symbolLayersForType(QgsSymbolV2::SymbolType type);
@@ -665,6 +671,7 @@ public:
 
 protected:
   QgsSymbolLayerV2Registry();
+  ~QgsSymbolLayerV2Registry();
 
 };
 
@@ -787,3 +794,57 @@ public:
   static void rendererV2toV1(QgsVectorLayer* layer);
 
 };
+
+////////////
+
+class QgsRendererV2Widget /External/;
+
+class QgsRendererV2AbstractMetadata
+{
+%TypeHeaderCode
+#include <qgsrendererv2registry.h>
+%End
+
+  public:
+    QgsRendererV2AbstractMetadata( QString name, QString visibleName, QString iconName = QString() );
+
+    QString name() const;
+    QString visibleName() const;
+    QString iconName() const;
+
+    /** Return new instance of the renderer given the DOM element. Returns NULL on error.
+     * Pure virtual function: must be implemented in derived classes.  */
+    virtual QgsFeatureRendererV2* createRenderer( QDomElement& elem ) = 0 /Factory/;
+    /** Return new instance of settings widget for the renderer. Returns NULL on error. */
+    virtual QgsRendererV2Widget* createRendererWidget( QgsVectorLayer* layer, QgsStyleV2* style, QgsFeatureRendererV2* renderer ) /Factory/;
+
+};
+
+
+class QgsRendererV2Registry
+{
+%TypeHeaderCode
+#include <qgsrendererv2registry.h>
+%End
+
+  public:
+
+    static QgsRendererV2Registry* instance();
+
+    //! add a renderer to registry. Takes ownership of the metadata object.
+    bool addRenderer( QgsRendererV2AbstractMetadata* metadata /Transfer/ );
+
+    //! remove renderer from registry
+    bool removeRenderer( QString rendererName );
+
+    //! get metadata for particular renderer. Returns NULL if not found in registry.
+    QgsRendererV2AbstractMetadata* rendererMetadata( QString rendererName );
+
+    //! return a list of available renderers
+    QStringList renderersList();
+
+  protected:
+    //! protected constructor
+    QgsRendererV2Registry();
+    ~QgsRendererV2Registry();
+};

python/gui/symbology-ng-gui.sip

@@ -96,3 +96,38 @@ signals:
   void symbolModified();
 
 };
+
+
+
+class QgsSymbolLayerV2Widget : QWidget
+{
+%TypeHeaderCode
+#include <qgssymbollayerv2widget.h>
+%End
+
+  public:
+    QgsSymbolLayerV2Widget( QWidget* parent );
+    virtual ~QgsSymbolLayerV2Widget();
+
+    virtual void setSymbolLayer( QgsSymbolLayerV2* layer ) = 0;
+    virtual QgsSymbolLayerV2* symbolLayer() = 0;
+
+  signals:
+    void changed();
+};
+
+class QgsRendererV2Widget : QWidget
+{
+%TypeHeaderCode
+#include <qgsrendererv2widget.h>
+%End
+
+  public:
+    QgsRendererV2Widget( QgsVectorLayer* layer, QgsStyleV2* style );
+
+    virtual ~QgsRendererV2Widget();
+
+    //! return pointer to the renderer (no transfer of ownership)
+    virtual QgsFeatureRendererV2* renderer() = 0;
+
+};

src/core/symbology-ng/qgsrendererv2.cpp

@@ -311,13 +311,11 @@ QgsFeatureRendererV2* QgsFeatureRendererV2::load( QDomElement& element )
   // load renderer
   QString rendererType = element.attribute( "type" );
 
-  QgsRendererV2CreateFunc pfCreate = QgsRendererV2Registry::instance()->rendererMetadata( rendererType ).createFunction();
-
-  // unknown renderer type?
-  if ( pfCreate == NULL )
+  QgsRendererV2AbstractMetadata* m = QgsRendererV2Registry::instance()->rendererMetadata( rendererType );
+  if (m == NULL)
     return NULL;
 
-  QgsFeatureRendererV2* r = pfCreate( element );
+  QgsFeatureRendererV2* r = m->createRenderer( element );
   if ( r )
     r->setUsingSymbolLevels( element.attribute( "symbollevels", "0" ).toInt() );
 

src/core/symbology-ng/qgsrendererv2registry.cpp

@@ -11,20 +11,29 @@ QgsRendererV2Registry* QgsRendererV2Registry::mInstance = NULL;
 QgsRendererV2Registry::QgsRendererV2Registry()
 {
   // add default renderers
-  addRenderer( QgsRendererV2Metadata( "singleSymbol",
+  addRenderer( new QgsRendererV2Metadata( "singleSymbol",
                                       QObject::tr( "Single Symbol" ),
                                       QgsSingleSymbolRendererV2::create,
                                       "rendererSingleSymbol.png" ) );
-  addRenderer( QgsRendererV2Metadata( "categorizedSymbol",
+  addRenderer( new QgsRendererV2Metadata( "categorizedSymbol",
                                       QObject::tr( "Categorized" ),
                                       QgsCategorizedSymbolRendererV2::create,
                                       "rendererCategorizedSymbol.png" ) );
-  addRenderer( QgsRendererV2Metadata( "graduatedSymbol",
+  addRenderer( new QgsRendererV2Metadata( "graduatedSymbol",
                                       QObject::tr( "Graduated" ),
                                       QgsGraduatedSymbolRendererV2::create,
                                       "rendererGraduatedSymbol.png" ) );
 }
 
+QgsRendererV2Registry::~QgsRendererV2Registry()
+{
+  foreach (QString name, mRenderers.keys())
+  {
+    delete mRenderers[name];
+  }
+  mRenderers.clear();
+}
+
 QgsRendererV2Registry* QgsRendererV2Registry::instance()
 {
   if ( !mInstance )
@@ -34,34 +43,32 @@ QgsRendererV2Registry* QgsRendererV2Registry::instance()
 }
 
 
-void QgsRendererV2Registry::addRenderer( const QgsRendererV2Metadata& metadata )
+bool QgsRendererV2Registry::addRenderer( QgsRendererV2AbstractMetadata* metadata )
 {
-  mRenderers[metadata.name()] = metadata;
-  mRenderersOrder << metadata.name();
+  if (metadata == NULL || mRenderers.contains(metadata->name()) )
+    return false;
+
+  mRenderers[metadata->name()] = metadata;
+  mRenderersOrder << metadata->name();
+  return true;
 }
 
 bool QgsRendererV2Registry::removeRenderer( QString rendererName )
 {
   if ( !mRenderers.contains( rendererName ) )
     return false;
+
+  delete mRenderers[rendererName];
   mRenderers.remove( rendererName );
   mRenderersOrder.removeAll( rendererName );
   return true;
 }
 
-QgsRendererV2Metadata QgsRendererV2Registry::rendererMetadata( QString rendererName )
+QgsRendererV2AbstractMetadata* QgsRendererV2Registry::rendererMetadata( QString rendererName )
 {
   return mRenderers.value( rendererName );
 }
 
-bool QgsRendererV2Registry::setRendererWidgetFunction( QString name, QgsRendererV2WidgetFunc f )
-{
-  if ( !mRenderers.contains( name ) )
-    return false;
-  mRenderers[name].setWidgetFunction( f );
-  return true;
-}
-
 QStringList QgsRendererV2Registry::renderersList()
 {
   return mRenderersOrder;

src/core/symbology-ng/qgsrendererv2registry.h

@@ -10,41 +10,69 @@ class QgsVectorLayer;
 class QgsStyleV2;
 class QgsRendererV2Widget;
 
+/**
+ Stores metadata about one renderer class.
+
+ @note It's necessary to implement createRenderer() function.
+   In C++ you can use QgsRendererV2Metadata convenience class.
+ */
+class CORE_EXPORT QgsRendererV2AbstractMetadata
+{
+  public:
+    QgsRendererV2AbstractMetadata( QString name, QString visibleName, QString iconName = QString() )
+        : mName( name ), mVisibleName( visibleName ), mIconName( iconName ) {}
+
+    QString name() const { return mName; }
+    QString visibleName() const { return mVisibleName; }
+    QString iconName() const { return mIconName; }
+
+    /** Return new instance of the renderer given the DOM element. Returns NULL on error.
+     * Pure virtual function: must be implemented in derived classes.  */
+    virtual QgsFeatureRendererV2* createRenderer( QDomElement& elem ) = 0;
+    /** Return new instance of settings widget for the renderer. Returns NULL on error. */
+    virtual QgsRendererV2Widget* createRendererWidget( QgsVectorLayer* layer, QgsStyleV2* style, QgsFeatureRendererV2* renderer )
+      { return NULL; }
+
+  protected:
+    //! name used within QGIS for identification (the same what renderer's type() returns)
+    QString mName;
+    //! name visible for users (translatable)
+    QString mVisibleName;
+    //! icon to be shown in the renderer properties dialog
+    QString mIconName;
+};
+
+
 typedef QgsFeatureRendererV2*( *QgsRendererV2CreateFunc )( QDomElement& );
 typedef QgsRendererV2Widget*( *QgsRendererV2WidgetFunc )( QgsVectorLayer*, QgsStyleV2*, QgsFeatureRendererV2* );
 
-class CORE_EXPORT QgsRendererV2Metadata
+/**
+ Convenience metadata class that uses static functions to create renderer and its widget.
+ */
+class CORE_EXPORT QgsRendererV2Metadata : public QgsRendererV2AbstractMetadata
 {
   public:
-    /** construct invalid metadata */
-    QgsRendererV2Metadata()
-        : mName(), mVisibleName(), mCreateFunc( NULL ), mIconName(), mWidgetFunc( NULL ) {}
 
     /** construct metadata */
     QgsRendererV2Metadata( QString name,
                            QString visibleName,
                            QgsRendererV2CreateFunc pfCreate,
                            QString iconName = QString(),
                            QgsRendererV2WidgetFunc pfWidget = NULL )
-        : mName( name ), mVisibleName( visibleName ), mCreateFunc( pfCreate ), mIconName( iconName ), mWidgetFunc( pfWidget ) {}
+        : QgsRendererV2AbstractMetadata( name, visibleName, iconName ), mCreateFunc( pfCreate ), mWidgetFunc( pfWidget ) {}
+
+    virtual QgsFeatureRendererV2* createRenderer( QDomElement& elem ) { return mCreateFunc ? mCreateFunc(elem):NULL; }
+    virtual QgsRendererV2Widget* createRendererWidget( QgsVectorLayer* layer, QgsStyleV2* style, QgsFeatureRendererV2* renderer )
+      { return mWidgetFunc ? mWidgetFunc(layer, style, renderer) : NULL; }
 
-    QString name() const { return mName; }
-    QString visibleName() const { return mVisibleName; }
-    QString iconName() const { return mIconName; }
     QgsRendererV2CreateFunc createFunction() const { return mCreateFunc; }
     QgsRendererV2WidgetFunc widgetFunction() const { return mWidgetFunc; }
 
     void setWidgetFunction( QgsRendererV2WidgetFunc f ) { mWidgetFunc = f; }
 
   protected:
-    //! name used within QGIS for identification (the same what renderer's type() returns)
-    QString mName;
-    //! name visible for users (translatable)
-    QString mVisibleName;
     //! pointer to function that creates an instance of the renderer when loading project / style
     QgsRendererV2CreateFunc mCreateFunc;
-    //! icon to be shown in the renderer properties dialog
-    QString mIconName;
     //! pointer to function that creates a widget for configuration of renderer's params
     QgsRendererV2WidgetFunc mWidgetFunc;
 };
@@ -60,28 +88,26 @@ class CORE_EXPORT QgsRendererV2Registry
 
     static QgsRendererV2Registry* instance();
 
-    //! add a renderer to registry
-    void addRenderer( const QgsRendererV2Metadata& metadata );
+    //! add a renderer to registry. Takes ownership of the metadata object.
+    bool addRenderer( QgsRendererV2AbstractMetadata* metadata );
 
     //! remove renderer from registry
     bool removeRenderer( QString rendererName );
 
-    //! get factory method for particular renderer
-    QgsRendererV2Metadata rendererMetadata( QString rendererName );
-
-    //! assign a widget factory to particular renderer
-    bool setRendererWidgetFunction( QString name, QgsRendererV2WidgetFunc f );
+    //! get metadata for particular renderer. Returns NULL if not found in registry.
+    QgsRendererV2AbstractMetadata* rendererMetadata( QString rendererName );
 
     //! return a list of available renderers
     QStringList renderersList();
 
   protected:
     //! protected constructor
     QgsRendererV2Registry();
+    ~QgsRendererV2Registry();
 
     static QgsRendererV2Registry* mInstance;
 
-    QMap<QString, QgsRendererV2Metadata> mRenderers;
+    QMap<QString, QgsRendererV2AbstractMetadata*> mRenderers;
 
     //! list to keep order in which renderers have been added
     QStringList mRenderersOrder;