[FEATURE] labels support in QgsPalettedRasterRenderer, fixes #8886

python/core/raster/qgspalettedrasterrenderer.sip

@@ -5,7 +5,7 @@ class QgsPalettedRasterRenderer : QgsRasterRenderer
 %End
   public:
     /**Renderer owns color array*/
-    QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QColor* colorArray /Array,Transfer/, int nColors /ArraySize/ );
+    QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QColor* colorArray /Array,Transfer/, int nColors /ArraySize/, const QVector<QString> labels = QVector<QString>() );
     ~QgsPalettedRasterRenderer();
     QgsRasterInterface * clone() const /Factory/;
     static QgsRasterRenderer* create( const QDomElement& elem, QgsRasterInterface* input ) /Factory/;

src/core/qgsprojectfiletransform.cpp

@@ -774,6 +774,11 @@ void QgsProjectFileTransform::convertRasterProperties( QDomDocument& doc, QDomNo
       green = colorRampEntryElem.attribute( "green" ).toInt();
       blue = colorRampEntryElem.attribute( "blue" ).toInt();
       newPaletteElem.setAttribute( "color", QColor( red, green, blue ).name() );
+      QString label = colorRampEntryElem.attribute( "label" );
+      if ( !label.isEmpty() )
+      {
+        newPaletteElem.setAttribute( "label", label );
+      }
       newColorPaletteElem.appendChild( newPaletteElem );
     }
     rasterRendererElem.appendChild( newColorPaletteElem );

src/core/raster/qgspalettedrasterrenderer.cpp

@@ -22,10 +22,11 @@
 #include <QDomDocument>
 #include <QDomElement>
 #include <QImage>
+#include <QVector>
 
 QgsPalettedRasterRenderer::QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber,
-    QColor* colorArray, int nColors ):
-    QgsRasterRenderer( input, "paletted" ), mBand( bandNumber ), mNColors( nColors )
+    QColor* colorArray, int nColors, const QVector<QString> labels ):
+    QgsRasterRenderer( input, "paletted" ), mBand( bandNumber ), mNColors( nColors ), mLabels( labels )
 {
   mColors = new QRgb[nColors];
   for ( int i = 0; i < nColors; ++i )
@@ -35,8 +36,8 @@ QgsPalettedRasterRenderer::QgsPalettedRasterRenderer( QgsRasterInterface* input,
   delete[] colorArray;
 }
 
-QgsPalettedRasterRenderer::QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QRgb* colorArray, int nColors ):
-    QgsRasterRenderer( input, "paletted" ), mBand( bandNumber ), mColors( colorArray ), mNColors( nColors )
+QgsPalettedRasterRenderer::QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QRgb* colorArray, int nColors, const QVector<QString> labels ):
+    QgsRasterRenderer( input, "paletted" ), mBand( bandNumber ), mColors( colorArray ), mNColors( nColors ), mLabels( labels )
 {
 }
 
@@ -51,6 +52,7 @@ QgsRasterInterface * QgsPalettedRasterRenderer::clone() const
   renderer->setOpacity( mOpacity );
   renderer->setAlphaBand( mAlphaBand );
   renderer->setRasterTransparency( mRasterTransparency );
+  renderer->mLabels = mLabels;
   return renderer;
 }
 
@@ -64,6 +66,7 @@ QgsRasterRenderer* QgsPalettedRasterRenderer::create( const QDomElement& elem, Q
   int bandNumber = elem.attribute( "band", "-1" ).toInt();
   int nColors = 0;
   QRgb* colors = 0;
+  QVector<QString> labels;
 
   QDomElement paletteElem = elem.firstChildElement( "colorPalette" );
   if ( !paletteElem.isNull() )
@@ -94,14 +97,20 @@ QgsRasterRenderer* QgsPalettedRasterRenderer::create( const QDomElement& elem, Q
       if ( value >= 0 && value < nColors )
       {
         colors[value] = QColor( entryElem.attribute( "color", "#000000" ) ).rgba();
+        QString label = entryElem.attribute( "label" );
+        if ( !label.isEmpty() )
+        {
+          if ( value >= labels.size() ) labels.resize( value + 1 );
+          labels[value] = label;
+        }
       }
       else
       {
         QgsDebugMsg( QString( "value %1 out of range" ).arg( value ) );
       }
     }
   }
-  QgsRasterRenderer* r = new QgsPalettedRasterRenderer( input, bandNumber, colors, nColors );
+  QgsPalettedRasterRenderer* r = new QgsPalettedRasterRenderer( input, bandNumber, colors, nColors, labels );
   r->readXML( elem );
   return r;
 }
@@ -134,6 +143,15 @@ QRgb* QgsPalettedRasterRenderer::rgbArray() const
   return rgbValues;
 }
 
+void QgsPalettedRasterRenderer::setLabel( int idx, QString label )
+{
+  if ( idx >= mLabels.size() )
+  {
+    mLabels.resize( idx + 1 );
+  }
+  mLabels[idx] = label;
+}
+
 QgsRasterBlock * QgsPalettedRasterRenderer::block( int bandNo, QgsRectangle  const & extent, int width, int height )
 {
   QgsRasterBlock *outputBlock = new QgsRasterBlock();
@@ -240,6 +258,10 @@ void QgsPalettedRasterRenderer::writeXML( QDomDocument& doc, QDomElement& parent
     QDomElement colorElem = doc.createElement( "paletteEntry" );
     colorElem.setAttribute( "value", i );
     colorElem.setAttribute( "color", QColor( mColors[i] ).name() );
+    if ( !label( i ).isEmpty() )
+    {
+      colorElem.setAttribute( "label", label( i ) );
+    }
     colorPaletteElem.appendChild( colorElem );
   }
   rasterRendererElem.appendChild( colorPaletteElem );
@@ -251,7 +273,8 @@ void QgsPalettedRasterRenderer::legendSymbologyItems( QList< QPair< QString, QCo
 {
   for ( int i = 0; i < mNColors; ++i )
   {
-    symbolItems.push_back( qMakePair( QString::number( i ), QColor( mColors[i] ) ) );
+    QString lab = label( i ).isEmpty() ? QString::number( i ) : label( i );
+    symbolItems.push_back( qMakePair( lab, QColor( mColors[i] ) ) );
   }
 }
 

src/core/raster/qgspalettedrasterrenderer.h

@@ -18,6 +18,8 @@
 #ifndef QGSPALETTEDRASTERRENDERER_H
 #define QGSPALETTEDRASTERRENDERER_H
 
+#include <QVector>
+
 #include "qgsrasterrenderer.h"
 
 class QColor;
@@ -30,8 +32,8 @@ class CORE_EXPORT QgsPalettedRasterRenderer: public QgsRasterRenderer
 {
   public:
     /**Renderer owns color array*/
-    QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QColor* colorArray, int nColors );
-    QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QRgb* colorArray, int nColors );
+    QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QColor* colorArray, int nColors, const QVector<QString> labels = QVector<QString>() );
+    QgsPalettedRasterRenderer( QgsRasterInterface* input, int bandNumber, QRgb* colorArray, int nColors, const QVector<QString> labels = QVector<QString>() );
     ~QgsPalettedRasterRenderer();
     QgsRasterInterface * clone() const;
     static QgsRasterRenderer* create( const QDomElement& elem, QgsRasterInterface* input );
@@ -48,6 +50,14 @@ class CORE_EXPORT QgsPalettedRasterRenderer: public QgsRasterRenderer
      */
     QRgb* rgbArray() const;
 
+    /** Return optional category label
+     *  @note added in 2.1 */
+    QString label( int idx ) const { return mLabels.value( idx ); }
+
+    /** Set category label
+     *  @note added in 2.1 */
+    void setLabel( int idx, QString label );
+
     void writeXML( QDomDocument& doc, QDomElement& parentElem ) const;
 
     void legendSymbologyItems( QList< QPair< QString, QColor > >& symbolItems ) const;
@@ -60,6 +70,8 @@ class CORE_EXPORT QgsPalettedRasterRenderer: public QgsRasterRenderer
     QRgb* mColors;
     /**Number of colors*/
     int mNColors;
+    /** Optional category labels, size of vector may be < mNColors */
+    QVector<QString> mLabels;
 };
 
 #endif // QGSPALETTEDRASTERRENDERER_H

src/gui/raster/qgspalettedrendererwidget.cpp

@@ -52,24 +52,36 @@ QgsRasterRenderer* QgsPalettedRendererWidget::renderer()
 {
   int nColors = mTreeWidget->topLevelItemCount();
   QColor* colorArray = new QColor[nColors];
+  QVector<QString> labels;
   for ( int i = 0; i < nColors; ++i )
   {
     colorArray[i] = mTreeWidget->topLevelItem( i )->background( 1 ).color();
+    QString label = mTreeWidget->topLevelItem( i )->text( 2 );
+    if ( !label.isEmpty() )
+    {
+      if ( i >= labels.size() ) labels.resize( i + 1 );
+      labels[i] = label;
+    }
   }
   int bandNumber = mBandComboBox->itemData( mBandComboBox->currentIndex() ).toInt();
-  return new QgsPalettedRasterRenderer( mRasterLayer->dataProvider(), bandNumber, colorArray, nColors );
+  return new QgsPalettedRasterRenderer( mRasterLayer->dataProvider(), bandNumber, colorArray, nColors, labels );
 }
 
 void QgsPalettedRendererWidget::on_mTreeWidget_itemDoubleClicked( QTreeWidgetItem * item, int column )
 {
   if ( column == 1 && item ) //change item color
   {
+    item->setFlags( Qt::ItemIsEnabled | Qt::ItemIsSelectable );
     QColor c = QColorDialog::getColor( item->background( column ).color() );
     if ( c.isValid() )
     {
       item->setBackground( column, QBrush( c ) );
     }
   }
+  else if ( column == 2 && item )
+  {
+    item->setFlags( Qt::ItemIsEnabled | Qt::ItemIsEditable | Qt::ItemIsSelectable );
+  }
 }
 
 void QgsPalettedRendererWidget::setFromRenderer( const QgsRasterRenderer* r )
@@ -85,6 +97,7 @@ void QgsPalettedRendererWidget::setFromRenderer( const QgsRasterRenderer* r )
       QTreeWidgetItem* item = new QTreeWidgetItem( mTreeWidget );
       item->setText( 0, QString::number( i ) );
       item->setBackground( 1, QBrush( colors[i] ) );
+      item->setText( 2, pr->label( i ) );
     }
     delete[] colors;
   }
@@ -102,6 +115,7 @@ void QgsPalettedRendererWidget::setFromRenderer( const QgsRasterRenderer* r )
         QTreeWidgetItem* item = new QTreeWidgetItem( mTreeWidget );
         item->setText( 0, QString::number( index ) );
         item->setBackground( 1, QBrush( itemIt->color ) );
+        item->setText( 2, itemIt->label );
         ++index;
       }
     }

src/ui/qgspalettedrendererwidgetbase.ui

@@ -42,6 +42,9 @@
        <height>280</height>
       </size>
      </property>
+     <property name="columnCount">
+      <number>3</number>
+     </property>
      <column>
       <property name="text">
        <string>Value</string>
@@ -52,6 +55,11 @@
        <string>Color</string>
       </property>
      </column>
+     <column>
+      <property name="text">
+       <string>Label</string>
+      </property>
+     </column>
     </widget>
    </item>
   </layout>