Allow customisation of color ramp legend items in a print layout legend

qgis · Dec 18, 2020 · 24549f05fdba156c9f231def85fefe43adcf1286 · 24549f0
1 parent 55dbd9c
commit 24549f05fdba156c9f231def85fefe43adcf1286
diff --git a/python/core/auto_generated/layertree/qgscolorramplegendnode.sip.in b/python/core/auto_generated/layertree/qgscolorramplegendnode.sip.in
@@ -55,7 +55,6 @@ Constructor for QgsColorRampLegendNode.
     virtual QSizeF drawSymbolText( const QgsLegendSettings &settings, ItemContext *ctx, QSizeF symbolSize ) const;
 
 
-
     void setIconSize( QSize size );
 %Docstring
 Set the icon ``size``, which controls how large the ramp will render in a layer tree widget.
@@ -73,6 +72,20 @@ Returns the icon size, which is how large the ramp will render in a layer tree w
     const QgsColorRamp *ramp() const;
 %Docstring
 Returns the color ramp used by the node.
+%End
+
+    QgsColorRampLegendNodeSettings settings() const;
+%Docstring
+Returns the node's settings.
+
+.. seealso:: :py:func:`setSettings`
+%End
+
+    void setSettings( const QgsColorRampLegendNodeSettings &settings );
+%Docstring
+Sets the node's ``settings``.
+
+.. seealso:: :py:func:`settings`
 %End
 
 };

diff --git a/python/core/auto_generated/qgsmaplayerlegend.sip.in b/python/core/auto_generated/qgsmaplayerlegend.sip.in
@@ -147,7 +147,7 @@ symbol width or height from :py:class:`QgsLegendSettings`.
 
     static void setLegendNodeCustomSymbol( QgsLayerTreeLayer *nodeLayer, int originalIndex, const QgsSymbol *symbol );
 %Docstring
-Sets a custom legend ``symbol`` size for the legend node belonging to ``nodeLayer`` at the specified ``originalIndex``.
+Sets a custom legend ``symbol`` for the legend node belonging to ``nodeLayer`` at the specified ``originalIndex``.
 
 If ``symbol`` is non-``None``, it will be used in place of the default symbol when rendering
 the legend node.
@@ -171,6 +171,37 @@ Caller takes ownership of the returned symbol.
 .. versionadded:: 3.14
 %End
 
+    static void setLegendNodeColorRampSettings( QgsLayerTreeLayer *nodeLayer, int originalIndex, const QgsColorRampLegendNodeSettings *settings );
+%Docstring
+Sets a custom legend color ramp ``settings`` for the legend node belonging to ``nodeLayer`` at the specified ``originalIndex``.
+
+If the corresponding legend node is not a QgsColorRampLegendNode then calling this method will have no effect.
+
+If ``settings`` is non-``None``, they will be used in place of the default settigns when rendering
+the legend node.
+
+.. seealso:: :py:func:`legendNodeColorRampSettings`
+
+.. versionadded:: 3.18
+%End
+
+    static QgsColorRampLegendNodeSettings *legendNodeColorRampSettings( QgsLayerTreeLayer *nodeLayer, int originalIndex ) /Factory/;
+%Docstring
+Returns the custom legend color ramp settings for the legend node belonging to ``nodeLayer`` at the specified ``originalIndex``.
+
+If the corresponding legend node is not a QgsColorRampLegendNode then calling this method will return ``None``.
+
+If the returned value is non-``None``, they will be used in place of the default settings when rendering
+the legend node.
+
+Caller takes ownership of the returned settings.
+
+.. seealso:: :py:func:`setLegendNodeColorRampSettings`
+
+.. versionadded:: 3.18
+%End
+
+
     static void setLegendNodeColumnBreak( QgsLayerTreeLayer *nodeLayer, int originalIndex, bool columnBreakBeforeNode );
 %Docstring
 Sets whether a forced column break should occur before the node.

diff --git a/src/core/layertree/qgscolorramplegendnode.cpp b/src/core/layertree/qgscolorramplegendnode.cpp
@@ -39,14 +39,9 @@ QgsColorRampLegendNode::QgsColorRampLegendNode( QgsLayerTreeLayer *nodeLayer, Qg
   : QgsLayerTreeModelLegendNode( nodeLayer, parent )
   , mRamp( ramp )
   , mSettings( settings )
+  , mMinimumValue( minimumValue )
+  , mMaximumValue( maximumValue )
 {
-  QgsNumericFormatContext numericContext;
-  if ( mSettings.minimumLabel().isEmpty() )
-    mSettings.setMinimumLabel( settings.numericFormat()->formatDouble( minimumValue, numericContext ) );
-
-  if ( mSettings.maximumLabel().isEmpty() )
-    mSettings.setMaximumLabel( settings.numericFormat()->formatDouble( maximumValue, numericContext ) );
-
   const int iconSize = QgsLayerTreeModel::scaleIconSize( 16 );
   mIconSize = QSize( iconSize, iconSize * 6 );
 
@@ -58,6 +53,34 @@ const QgsColorRamp *QgsColorRampLegendNode::ramp() const
   return mRamp.get();
 }
 
+QgsColorRampLegendNodeSettings QgsColorRampLegendNode::settings() const
+{
+  return mSettings;
+}
+
+void QgsColorRampLegendNode::setSettings( const QgsColorRampLegendNodeSettings &settings )
+{
+  mSettings = settings;
+}
+
+QString QgsColorRampLegendNode::labelForMinimum() const
+{
+  if ( !mSettings.minimumLabel().isEmpty() )
+    return mSettings.prefix() + mSettings.minimumLabel() + mSettings.suffix();
+
+  QgsNumericFormatContext numericContext;
+  return mSettings.prefix() + mSettings.numericFormat()->formatDouble( mMinimumValue, numericContext )  + mSettings.suffix();
+}
+
+QString QgsColorRampLegendNode::labelForMaximum() const
+{
+  if ( !mSettings.maximumLabel().isEmpty() )
+    return mSettings.prefix() + mSettings.maximumLabel() + mSettings.suffix();
+
+  QgsNumericFormatContext numericContext;
+  return mSettings.prefix() + mSettings.numericFormat()->formatDouble( mMaximumValue, numericContext ) + mSettings.suffix();
+}
+
 QVariant QgsColorRampLegendNode::data( int role ) const
 {
   if ( role == Qt::DisplayRole )
@@ -86,8 +109,8 @@ QVariant QgsColorRampLegendNode::data( int role ) const
 
       const QFont font = data( Qt::FontRole ).value< QFont >();
 
-      const QString minLabel = mSettings.prefix() + mSettings.minimumLabel() + mSettings.suffix();
-      const QString maxLabel = mSettings.prefix() + mSettings.maximumLabel() + mSettings.suffix();
+      const QString minLabel = labelForMinimum();
+      const QString maxLabel = labelForMaximum();
 
       const QFontMetrics fm( font );
       const int maxTextWidth = std::max( fm.boundingRect( minLabel ).width(), fm.boundingRect( maxLabel ).width() );
@@ -152,8 +175,8 @@ QSizeF QgsColorRampLegendNode::drawSymbol( const QgsLegendSettings &settings, It
   QgsTextFormat format = QgsTextFormat::fromQFont( symbolLabelFont );
   format.setColor( settings.fontColor() );
 
-  const QString minLabel = mSettings.prefix() + mSettings.minimumLabel() + mSettings.suffix();
-  const QString maxLabel = mSettings.prefix() + mSettings.maximumLabel() + mSettings.suffix();
+  const QString minLabel = labelForMinimum();
+  const QString maxLabel = labelForMaximum();
 
   double minHeightMm = QgsTextRenderer::textHeight( *context, format, QStringList() << minLabel << maxLabel, QgsTextRenderer::Rect ) / context->scaleFactor();
 
@@ -259,8 +282,8 @@ QSizeF QgsColorRampLegendNode::drawSymbolText( const QgsLegendSettings &settings
   QgsTextFormat format = QgsTextFormat::fromQFont( symbolLabelFont );
   format.setColor( settings.fontColor() );
 
-  const QString minLabel = mSettings.prefix() + mSettings.minimumLabel() + mSettings.suffix();
-  const QString maxLabel = mSettings.prefix() + mSettings.maximumLabel() + mSettings.suffix();
+  const QString minLabel = labelForMinimum();
+  const QString maxLabel = labelForMaximum();
 
   const double height = symbolSize.height();
   const double width = symbolSize.width();

diff --git a/src/core/layertree/qgscolorramplegendnode.h b/src/core/layertree/qgscolorramplegendnode.h
@@ -65,7 +65,6 @@ class CORE_EXPORT QgsColorRampLegendNode : public QgsLayerTreeModelLegendNode
     QSizeF drawSymbol( const QgsLegendSettings &settings, ItemContext *ctx, double itemHeight ) const override;
     QSizeF drawSymbolText( const QgsLegendSettings &settings, ItemContext *ctx, QSizeF symbolSize ) const override;
 
-
     /**
      * Set the icon \a size, which controls how large the ramp will render in a layer tree widget.
      *
@@ -85,13 +84,32 @@ class CORE_EXPORT QgsColorRampLegendNode : public QgsLayerTreeModelLegendNode
      */
     const QgsColorRamp *ramp() const;
 
+    /**
+     * Returns the node's settings.
+     *
+     * \see setSettings()
+     */
+    QgsColorRampLegendNodeSettings settings() const;
+
+    /**
+     * Sets the node's \a settings.
+     *
+     * \see settings()
+     */
+    void setSettings( const QgsColorRampLegendNodeSettings &settings );
+
   private:
+    QString labelForMinimum() const;
+    QString labelForMaximum() const;
+
     std::unique_ptr< QgsColorRamp > mRamp;
 
     mutable QPixmap mPixmap; // cached symbol preview
     QSize mIconSize;
 
     QgsColorRampLegendNodeSettings mSettings;
+    double mMinimumValue = 0;
+    double mMaximumValue = 0;
 
 };
 

diff --git a/src/core/qgsmaplayerlegend.cpp b/src/core/qgsmaplayerlegend.cpp
@@ -225,6 +225,40 @@ QgsSymbol *QgsMapLayerLegendUtils::legendNodeCustomSymbol( QgsLayerTreeLayer *no
   return QgsSymbolLayerUtils::loadSymbol( elem, rwContext );
 }
 
+void QgsMapLayerLegendUtils::setLegendNodeColorRampSettings( QgsLayerTreeLayer *nodeLayer, int originalIndex, const QgsColorRampLegendNodeSettings *settings )
+{
+  if ( settings )
+  {
+    QDomDocument doc;
+    QgsReadWriteContext rwContext;
+    rwContext.setPathResolver( QgsProject::instance()->pathResolver() );
+    QDomElement elem = doc.createElement( QStringLiteral( "rampSettings" ) );
+    settings->writeXml( doc, elem, rwContext );
+    doc.appendChild( elem );
+    nodeLayer->setCustomProperty( "legend/custom-ramp-settings-" + QString::number( originalIndex ), doc.toString() );
+  }
+  else
+    nodeLayer->removeCustomProperty( "legend/custom-ramp-settings-" + QString::number( originalIndex ) );
+}
+
+QgsColorRampLegendNodeSettings *QgsMapLayerLegendUtils::legendNodeColorRampSettings( QgsLayerTreeLayer *nodeLayer, int originalIndex )
+{
+  const QString settingsDef = nodeLayer->customProperty( "legend/custom-ramp-settings-" + QString::number( originalIndex ) ).toString();
+  if ( settingsDef.isEmpty() )
+    return nullptr;
+
+  QDomDocument doc;
+  doc.setContent( settingsDef );
+  const QDomElement elem = doc.documentElement();
+
+  QgsReadWriteContext rwContext;
+  rwContext.setPathResolver( QgsProject::instance()->pathResolver() );
+
+  QgsColorRampLegendNodeSettings settings;
+  settings.readXml( elem, rwContext );
+  return new QgsColorRampLegendNodeSettings( settings );
+}
+
 void QgsMapLayerLegendUtils::setLegendNodeColumnBreak( QgsLayerTreeLayer *nodeLayer, int originalIndex, bool columnBreakBeforeNode )
 {
   if ( columnBreakBeforeNode )
@@ -256,6 +290,14 @@ void QgsMapLayerLegendUtils::applyLayerNodeProperties( QgsLayerTreeLayer *nodeLa
 
       symbolNode->setCustomSymbol( QgsMapLayerLegendUtils::legendNodeCustomSymbol( nodeLayer, i ) );
     }
+    else if ( QgsColorRampLegendNode *colorRampNode = dynamic_cast< QgsColorRampLegendNode * >( legendNode ) )
+    {
+      std::unique_ptr< QgsColorRampLegendNodeSettings > settings( QgsMapLayerLegendUtils::legendNodeColorRampSettings( nodeLayer, i ) );
+      if ( settings )
+      {
+        colorRampNode->setSettings( *settings );
+      }
+    }
 
     const QSizeF userSize = QgsMapLayerLegendUtils::legendNodeSymbolSize( nodeLayer, i );
     if ( userSize.isValid() )

diff --git a/src/core/qgsmaplayerlegend.h b/src/core/qgsmaplayerlegend.h
@@ -31,6 +31,7 @@ class QgsPointCloudLayer;
 class QgsReadWriteContext;
 class QgsVectorLayer;
 class QgsLegendPatchShape;
+class QgsColorRampLegendNodeSettings;
 class QgsSymbol;
 
 #include "qgis_core.h"
@@ -150,7 +151,7 @@ class CORE_EXPORT QgsMapLayerLegendUtils
     static QSizeF legendNodeSymbolSize( QgsLayerTreeLayer *nodeLayer, int originalIndex );
 
     /**
-     * Sets a custom legend \a symbol size for the legend node belonging to \a nodeLayer at the specified \a originalIndex.
+     * Sets a custom legend \a symbol for the legend node belonging to \a nodeLayer at the specified \a originalIndex.
      *
      * If \a symbol is non-NULLPTR, it will be used in place of the default symbol when rendering
      * the legend node.
@@ -173,6 +174,35 @@ class CORE_EXPORT QgsMapLayerLegendUtils
      */
     static QgsSymbol *legendNodeCustomSymbol( QgsLayerTreeLayer *nodeLayer, int originalIndex ) SIP_FACTORY;
 
+    /**
+     * Sets a custom legend color ramp \a settings for the legend node belonging to \a nodeLayer at the specified \a originalIndex.
+     *
+     * If the corresponding legend node is not a QgsColorRampLegendNode then calling this method will have no effect.
+     *
+     * If \a settings is non-NULLPTR, they will be used in place of the default settigns when rendering
+     * the legend node.
+     *
+     * \see legendNodeColorRampSettings()
+     * \since QGIS 3.18
+     */
+    static void setLegendNodeColorRampSettings( QgsLayerTreeLayer *nodeLayer, int originalIndex, const QgsColorRampLegendNodeSettings *settings );
+
+    /**
+     * Returns the custom legend color ramp settings for the legend node belonging to \a nodeLayer at the specified \a originalIndex.
+     *
+     * If the corresponding legend node is not a QgsColorRampLegendNode then calling this method will return NULLPTR.
+     *
+     * If the returned value is non-NULLPTR, they will be used in place of the default settings when rendering
+     * the legend node.
+     *
+     * Caller takes ownership of the returned settings.
+     *
+     * \see setLegendNodeColorRampSettings()
+     * \since QGIS 3.18
+     */
+    static QgsColorRampLegendNodeSettings *legendNodeColorRampSettings( QgsLayerTreeLayer *nodeLayer, int originalIndex ) SIP_FACTORY;
+
+
     /**
      * Sets whether a forced column break should occur before the node.
      *

diff --git a/src/gui/layout/qgslayoutlegendwidget.cpp b/src/gui/layout/qgslayoutlegendwidget.cpp
@@ -42,6 +42,7 @@
 #include "qgsexpressioncontextutils.h"
 #include "qgslegendpatchshapewidget.h"
 #include "qgslayertreefilterproxymodel.h"
+#include "qgscolorramplegendnodewidget.h"
 
 #include <QMenu>
 #include <QMessageBox>
@@ -1586,6 +1587,16 @@ QgsLayoutLegendNodeWidget::QgsLayoutLegendNodeWidget( QgsLayoutItemLegend *legen
     mPatchShapeButton->hide();
   }
 
+  if ( QgsColorRampLegendNode *colorRampNode = dynamic_cast< QgsColorRampLegendNode * >( mLegendNode ) )
+  {
+    mLabelGroup->hide();
+    mColorRampLegendWidget->setSettings( colorRampNode->settings() );
+  }
+  else
+  {
+    mColorRampLegendWidget->hide();
+  }
+
   if ( mLegendNode )
   {
     switch ( static_cast< QgsLayerTreeModelLegendNode::NodeTypes >( mLegendNode->data( QgsLayerTreeModelLegendNode::NodeTypeRole ).toInt() ) )
@@ -1619,6 +1630,8 @@ QgsLayoutLegendNodeWidget::QgsLayoutLegendNodeWidget( QgsLayoutItemLegend *legen
   connect( mColumnBreakBeforeCheckBox, &QCheckBox::toggled, this, &QgsLayoutLegendNodeWidget::columnBreakToggled );
 
   connect( mColumnSplitBehaviorComboBox, qgis::overload<int>::of( &QComboBox::currentIndexChanged ), this, &QgsLayoutLegendNodeWidget::columnSplitChanged );
+
+  connect( mColorRampLegendWidget, &QgsColorRampLegendNodeWidget::widgetChanged, this, &QgsLayoutLegendNodeWidget::colorRampLegendChanged );
 }
 
 void QgsLayoutLegendNodeWidget::labelChanged()
@@ -1791,6 +1804,19 @@ void QgsLayoutLegendNodeWidget::customSymbolChanged()
   mLegend->endCommand();
 }
 
+void QgsLayoutLegendNodeWidget::colorRampLegendChanged()
+{
+  mLegend->beginCommand( tr( "Edit Legend Item" ) );
+
+  QgsColorRampLegendNodeSettings settings = mColorRampLegendWidget->settings();
+  QgsMapLayerLegendUtils::setLegendNodeColorRampSettings( mLayer, mOriginalLegendNodeIndex, &settings );
+  mLegend->model()->refreshLayerLegend( mLayer );
+
+  mLegend->adjustBoxSize();
+  mLegend->updateFilterByMap();
+  mLegend->endCommand();
+}
+
 void QgsLayoutLegendNodeWidget::columnBreakToggled( bool checked )
 {
   mLegend->beginCommand( tr( "Edit Legend Columns" ) );

diff --git a/src/gui/layout/qgslayoutlegendwidget.h b/src/gui/layout/qgslayoutlegendwidget.h
@@ -197,6 +197,7 @@ class GUI_EXPORT QgsLayoutLegendNodeWidget: public QgsPanelWidget, private Ui::Q
     void insertExpression();
     void sizeChanged( double );
     void customSymbolChanged();
+    void colorRampLegendChanged();
     void columnBreakToggled( bool checked );
     void columnSplitChanged();