[FEATURE][diagrams] Add optional legend entries for diagram sizes

A new "legend" tab has been added to diagram properties, allowing both the existing attribute legend and a new size legend to be enabled/disabled. The size legend has a configurable marker symbol. Also includes unit tests for both diagram attribute and size legends. Sponsored by ADUGA
qgis · Apr 18, 2016 · efb84ea · efb84ea
1 parent e9c41e8
commit efb84ea
Show file tree

Hide file tree

Showing 25 changed files with 966 additions and 127 deletions.
diff --git a/images/images.qrc b/images/images.qrc
@@ -576,6 +576,7 @@
         <file>icons/qgis-icon-60x60_xmas.png</file>
         <file>themes/default/mActionTracing.png</file>
         <file>themes/default/vector_grid.png</file>
+        <file>themes/default/legend.svg</file>
         <file>themes/default/multieditChangedValues.svg</file>
         <file>themes/default/multieditMixedValues.svg</file>
         <file>themes/default/multieditSameValues.svg</file>

diff --git a/images/themes/default/legend.svg b/images/themes/default/legend.svg
diff --git a/python/core/diagram/qgsdiagram.sip b/python/core/diagram/qgsdiagram.sip
@@ -33,6 +33,14 @@ class QgsDiagram
     /** Returns the size in map units the diagram will use to render. Interpolate size*/
     virtual QSizeF diagramSize( const QgsFeature& feature, const QgsRenderContext& c, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) = 0;
 
+    /** Returns the size of the legend item for the diagram corresponding to a specified value.
+     * @param value value to return legend item size for
+     * @param s diagram settings
+     * @param is interpolation settings
+     * @note added in QGIS 2.16
+     */
+    virtual double legendSize( double value, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) const = 0;
+
   protected:
     QgsDiagram();
     QgsDiagram( const QgsDiagram& other );
@@ -69,4 +77,12 @@ class QgsDiagram
      *  @return The properly scaled font for rendering
      */
     QFont scaledFont( const QgsDiagramSettings& s, const QgsRenderContext& c );
+
+    /** Returns the scaled size of a diagram for a value, respecting the specified diagram interpolation settings.
+     * @param value value to calculate corresponding circular size for
+     * @param s diagram settings
+     * @param is interpolation settings
+     * @note added in QGIS 2.16
+     */
+    QSizeF sizeForValue( double value, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) const;
 };
diff --git a/python/core/diagram/qgshistogramdiagram.sip b/python/core/diagram/qgshistogramdiagram.sip
@@ -13,5 +13,6 @@ class QgsHistogramDiagram: QgsDiagram
 
     QSizeF diagramSize( const QgsAttributes& attributes, const QgsRenderContext& c, const QgsDiagramSettings& s );
     QSizeF diagramSize( const QgsFeature& feature, const QgsRenderContext& c, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is );
+    double legendSize( double value, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) const;
     QString diagramName() const;
 };
diff --git a/python/core/diagram/qgspiediagram.sip b/python/core/diagram/qgspiediagram.sip
@@ -13,5 +13,6 @@ class QgsPieDiagram: QgsDiagram
 
     QSizeF diagramSize( const QgsAttributes& attributes, const QgsRenderContext& c, const QgsDiagramSettings& s );
     QSizeF diagramSize( const QgsFeature& feature, const QgsRenderContext& c, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is );
+    double legendSize( double value, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) const;
     QString diagramName() const;
 };
diff --git a/python/core/diagram/qgstextdiagram.sip b/python/core/diagram/qgstextdiagram.sip
@@ -26,6 +26,7 @@ class QgsTextDiagram: QgsDiagram
 
     QSizeF diagramSize( const QgsAttributes& attributes, const QgsRenderContext& c, const QgsDiagramSettings& s );
     QSizeF diagramSize( const QgsFeature& feature, const QgsRenderContext& c, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is );
+    double legendSize( double value, const QgsDiagramSettings& s, const QgsDiagramInterpolationSettings& is ) const;
 
     QString diagramName() const;
 };
diff --git a/python/core/qgsdiagramrendererv2.sip b/python/core/qgsdiagramrendererv2.sip
@@ -410,7 +410,56 @@ class QgsDiagramRendererV2
      */
     virtual QList< QgsLayerTreeModelLegendNode* > legendItems( QgsLayerTreeLayer* nodeLayer ) const /Factory/;
 
+    /** Returns true if renderer will show legend items for diagram attributes.
+     * @note added in QGIS 2.16
+     * @see setAttributeLegend()
+     * @see sizeLegend()
+     */
+    bool attributeLegend() const;
+
+    /** Sets whether the renderer will show legend items for diagram attributes.
+     * @param enabled set to true to show diagram attribute legend
+     * @note added in QGIS 2.16
+     * @see attributeLegend()
+     * @see setSizeLegend()
+     */
+    void setAttributeLegend( bool enabled );
+
+    /** Returns true if renderer will show legend items for diagram sizes.
+     * @note added in QGIS 2.16
+     * @see setSizeLegend()
+     * @see attributeLegend()
+     * @see sizeLegendSymbol()
+     */
+    bool sizeLegend() const;
+
+    /** Sets whether the renderer will show legend items for diagram sizes.
+     * @param enabled set to true to show diagram size legend
+     * @note added in QGIS 2.16
+     * @see sizeLegend()
+     * @see setAttributeLegend()
+     * @see setSizeLegendSymbol()
+     */
+    void setSizeLegend( bool enabled );
+
+    /** Returns the marker symbol used for rendering the diagram size legend.
+     * @note added in QGIS 2.16
+     * @see setSizeLegendSymbol()
+     * @see sizeLegend()
+     */
+    QgsMarkerSymbolV2* sizeLegendSymbol() const;
+
+    /** Sets the marker symbol used for rendering the diagram size legend.
+     * @param symbol marker symbol, ownership is transferred to the renderer.
+     * @note added in QGIS 2.16
+     * @see sizeLegendSymbol()
+     * @see setSizeLegend()
+     */
+    void setSizeLegendSymbol( QgsMarkerSymbolV2* symbol /Transfer/ );
+
   protected:
+    QgsDiagramRendererV2( const QgsDiagramRendererV2& other );
+    //QgsDiagramRendererV2& operator=( const QgsDiagramRendererV2& other );
 
     /** Returns diagram settings for a feature (or false if the diagram for the feature is not to be rendered). Used internally within renderDiagram()
      * @param feature the feature