Merge pull request #966 from luipir/SITA3-WmsGetLegendGraphicManagement

WMS getLegendGraphic management in QgsLegend and QgsComposer - Developed with funding from Regione Toscana-SITA

Author: jef-n

src/app/composer/qgscomposerlegendwidget.cpp

@@ -168,6 +168,8 @@ void QgsComposerLegendWidget::setGuiElements()
   mEqualColumnWidthCheckBox->setChecked( mLegend->equalColumnWidth() );
   mSymbolWidthSpinBox->setValue( mLegend->symbolWidth() );
   mSymbolHeightSpinBox->setValue( mLegend->symbolHeight() );
+  mWmsLegendWidthSpinBox->setValue( mLegend->wmsLegendWidth() );
+  mWmsLegendHeightSpinBox->setValue( mLegend->wmsLegendHeight() );
   mTitleSpaceBottomSpinBox->setValue( mLegend->style( QgsComposerLegendStyle::Title ).margin( QgsComposerLegendStyle::Bottom ) );
   mGroupSpaceSpinBox->setValue( mLegend->style( QgsComposerLegendStyle::Group ).margin( QgsComposerLegendStyle::Top ) );
   mLayerSpaceSpinBox->setValue( mLegend->style( QgsComposerLegendStyle::Subgroup ).margin( QgsComposerLegendStyle::Top ) );
@@ -280,6 +282,30 @@ void QgsComposerLegendWidget::on_mSymbolHeightSpinBox_valueChanged( double d )
   }
 }
 
+void QgsComposerLegendWidget::on_mWmsLegendWidthSpinBox_valueChanged( double d )
+{
+  if ( mLegend )
+  {
+    mLegend->beginCommand( tr( "Wms Legend width" ), QgsComposerMergeCommand::LegendWmsLegendWidth );
+    mLegend->setWmsLegendWidth( d );
+    mLegend->adjustBoxSize();
+    mLegend->update();
+    mLegend->endCommand();
+  }
+}
+
+void QgsComposerLegendWidget::on_mWmsLegendHeightSpinBox_valueChanged( double d )
+{
+  if ( mLegend )
+  {
+    mLegend->beginCommand( tr( "Wms Legend height" ), QgsComposerMergeCommand::LegendWmsLegendHeight );
+    mLegend->setWmsLegendHeight( d );
+    mLegend->adjustBoxSize();
+    mLegend->update();
+    mLegend->endCommand();
+  }
+}
+
 void QgsComposerLegendWidget::on_mTitleSpaceBottomSpinBox_valueChanged( double d )
 {
   if ( mLegend )

src/app/composer/qgscomposerlegendwidget.h

@@ -59,6 +59,8 @@ class QgsComposerLegendWidget: public QWidget, private Ui::QgsComposerLegendWidg
     void on_mEqualColumnWidthCheckBox_toggled( bool checked );
     void on_mSymbolWidthSpinBox_valueChanged( double d );
     void on_mSymbolHeightSpinBox_valueChanged( double d );
+    void on_mWmsLegendWidthSpinBox_valueChanged( double d );
+    void on_mWmsLegendHeightSpinBox_valueChanged( double d );
     void on_mTitleSpaceBottomSpinBox_valueChanged( double d );
     void on_mGroupSpaceSpinBox_valueChanged( double d );
     void on_mLayerSpaceSpinBox_valueChanged( double d );

src/app/legend/qgslegend.cpp

@@ -113,6 +113,8 @@ QgsLegend::QgsLegend( QgsMapCanvas *canvas, QWidget * parent, const char *name )
 
   connect( mMapCanvas, SIGNAL( layersChanged() ),
            this, SLOT( refreshCheckStates() ) );
+  connect( mMapCanvas, SIGNAL( extentsChanged() ),
+           this, SLOT( updateLegendItemSymbologies() ) );
 
   // Initialise the line indicator widget.
   mInsertionLine = new QWidget( viewport() );
@@ -141,6 +143,7 @@ QgsLegend::QgsLegend( QgsMapCanvas *canvas, QWidget * parent, const char *name )
 QgsLegend::~QgsLegend()
 {
   delete mInsertionLine;
+  delete mGetLegendGraphicPopup;
 }
 
 #ifdef QGISDEBUG
@@ -395,6 +398,24 @@ void QgsLegend::mousePressEvent( QMouseEvent * e )
 {
   if ( e->button() == Qt::LeftButton )
   {
+    // show WMS legend in case itemAt( e->pos() ) is a wms legend
+    // if it's not a legend later it return a null pixmap
+    QImage legend = getWmsLegendPixmap( itemAt( e->pos() ) );
+    if ( !legend.isNull() )
+    {
+      mGetLegendGraphicPopup = new QFrame();
+      mGetLegendGraphicPopup->setFrameStyle(QFrame::Box | QFrame::Raised);
+      mGetLegendGraphicPopup->setLineWidth(2);
+      mGetLegendGraphicPopup->setAutoFillBackground(true);
+      QVBoxLayout *layout = new QVBoxLayout;
+      QLabel *label = new QLabel(mGetLegendGraphicPopup);
+      label->setPixmap( QPixmap::fromImage(legend) );
+      layout->addWidget(label);
+      mGetLegendGraphicPopup->setLayout(layout);
+      mGetLegendGraphicPopup->move(e->globalX(), e->globalY());
+      mGetLegendGraphicPopup->show();
+    }
+
     mMousePressedFlag = true;
     mDropTarget = itemAt( e->pos() );
     if ( !mDropTarget )
@@ -624,6 +645,11 @@ void QgsLegend::updateGroupCheckStates( QTreeWidgetItem *item )
 
 void QgsLegend::mouseReleaseEvent( QMouseEvent * e )
 {
+  if (mGetLegendGraphicPopup) {
+    delete mGetLegendGraphicPopup;
+    mGetLegendGraphicPopup = 0;
+  }
+  
   QStringList layersPriorToEvent = layerIDs();
   QTreeWidget::mouseReleaseEvent( e );
   mMousePressedFlag = false;
@@ -3208,3 +3234,43 @@ void QgsLegend::updateLegendItemSymbologies()
     ll->refreshSymbology( ll->layer()->id() );
   }
 }
+
+QImage QgsLegend::getWmsLegendPixmap( QTreeWidgetItem *item )
+{
+  if ( !item )
+  {
+    return QImage();
+  }
+
+  QTreeWidgetItem *parent = item->parent();
+  if ( !parent ) 
+  {
+    return QImage();
+  }
+
+  QgsLegendItem* li = dynamic_cast<QgsLegendItem *>( parent );
+  if ( !li )
+  {
+    return QImage();
+  }
+
+  if ( li->type() != QgsLegendItem::LEGEND_LAYER )
+  {
+    return QImage();
+  }
+
+  QgsLegendLayer *lyr = qobject_cast<QgsLegendLayer*>( li );
+  QgsRasterLayer *rasterLayer = dynamic_cast<QgsRasterLayer*>( lyr->layer() );
+  if ( !rasterLayer )
+  {
+    return QImage();
+  }
+
+  if ( rasterLayer->providerType() != "wms" )
+  {
+    return QImage();
+  }
+  
+  return rasterLayer->dataProvider()->getLegendGraphic( canvas()->scale() );
+}
+

src/app/legend/qgslegend.h

@@ -590,6 +590,16 @@ class QgsLegend : public QTreeWidget
 
     bool verifyDrawingOrder();
 
+    /*!
+     * Check if current LegendItem belogs to a WMS layer 
+     * @param item LegendItem to check if belongs to a WMS layer
+     * @return QImage A valid Legend image if belogs to WMS otherwise QImage()
+     */
+    QImage getWmsLegendPixmap( QTreeWidgetItem *item );
+
+    //! popup QFrame containing WMS getLegendGraphic pixmap
+    QFrame *mGetLegendGraphicPopup;
+
   signals:
     void itemAdded( QModelIndex index );
     void itemMoved( QModelIndex oldIndex, QModelIndex newIndex );

src/app/legend/qgslegendlayer.cpp

@@ -208,6 +208,26 @@ void QgsLegendLayer::rasterLayerSymbology( QgsRasterLayer* layer )
 #if QT_VERSION >= 0x40700
   itemList.reserve( rasterItemList.size() );
 #endif
+
+  // GetLegendGraphics in case of WMS service... pixmap can return null if GetLegendGraphics 
+  // is not supported by server
+  QgsDebugMsg( QString( "layer providertype:: %1" ).arg( layer->providerType() ) );
+  if ( layer->providerType() == "wms" )
+  {
+    double currentScale = legend()->canvas()->scale();
+
+    QImage legendGraphic = layer->dataProvider()->getLegendGraphic( currentScale );
+    if ( !legendGraphic.isNull() )
+    {
+      QgsDebugMsg( QString( "downloaded legend with dimension Width:" )+QString::number(legendGraphic.width())+QString(" and Height:")+QString::number(legendGraphic.height()) );
+      
+#if QT_VERSION >= 0x40700
+      if ( rasterItemList.size() == 0) itemList.reserve( 1 );
+#endif
+      itemList.append( qMakePair( QString(""), QPixmap::fromImage(legendGraphic) ) );
+    }
+  }
+
   // Paletted raster may have many colors, for example UInt16 may have 65536 colors
   // and it is very slow, so we limit max count
   QSize iconSize = treeWidget()->iconSize();

src/app/qgsoptions.cpp

@@ -545,6 +545,9 @@ QgsOptions::QgsOptions( QWidget *parent, Qt::WFlags fl ) :
 
   cmbLegendDoubleClickAction->setCurrentIndex( settings.value( "/qgis/legendDoubleClickAction", 0 ).toInt() );
 
+  // WMS getLegendGraphic setting
+  mLegendGraphicResolutionSpinBox->setValue( settings.value("/qgis/defaultLegendGraphicResolution", 0).toInt() );
+
   //
   // Raster properties
   //
@@ -965,6 +968,7 @@ void QgsOptions::saveOptions()
   settings.setValue( "/qgis/addPostgisDC", cbxAddPostgisDC->isChecked() );
   settings.setValue( "/qgis/addOracleDC", cbxAddOracleDC->isChecked() );
   settings.setValue( "/qgis/addNewLayersToCurrentGroup", cbxAddNewLayersToCurrentGroup->isChecked() );
+  settings.setValue( "/qgis/defaultLegendGraphicResolution", mLegendGraphicResolutionSpinBox->value() );
   bool createRasterLegendIcons = settings.value( "/qgis/createRasterLegendIcons", false ).toBool();
   settings.setValue( "/qgis/createRasterLegendIcons", cbxCreateRasterLegendIcons->isChecked() );
   settings.setValue( "/qgis/copyGeometryAsWKT", cbxCopyWKTGeomFromTable->isChecked() );

src/core/composer/qgscomposeritemcommand.h

@@ -85,6 +85,8 @@ class CORE_EXPORT QgsComposerMergeCommand: public QgsComposerItemCommand
       LegendEqualColumnWidth,
       LegendSymbolWidth,
       LegendSymbolHeight,
+      LegendWmsLegendWidth,
+      LegendWmsLegendHeight,
       LegendTitleSpaceBottom,
       LegendGroupSpace,
       LegendLayerSpace,

src/core/composer/qgscomposerlegend.cpp

@@ -54,6 +54,8 @@ QgsComposerLegend::QgsComposerLegend( QgsComposition* composition )
 
   mSymbolWidth = 7;
   mSymbolHeight = 4;
+  mWmsLegendWidth = 50;
+  mWmsLegendHeight = 25;
   mWrapChar = "";
   mlineSpacing = 1.5;
   adjustBoxSize();
@@ -347,13 +349,41 @@ QgsComposerLegend::Nucleon QgsComposerLegend::drawSymbolItem( QgsComposerLegendI
   }
   else if ( rasterItem )
   {
-    if ( painter )
+    // manage WMS lengendGraphic
+    // actual code recognise if it's a legend because it has an icon and it's text is empty => this is not good MV pattern implementation :(
+    QIcon symbolIcon = symbolItem->icon();
+    if ( !symbolIcon.isNull() && symbolItem->text().isEmpty() )
     {
-      painter->setBrush( rasterItem->color() );
-      painter->drawRect( QRectF( point.x(), point.y() + ( itemHeight - mSymbolHeight ) / 2, mSymbolWidth, mSymbolHeight ) );
+      // find max size
+      QList<QSize> sizes = symbolIcon.availableSizes();
+      double maxWidth = 0;
+      double maxHeight = 0;
+      foreach ( QSize size, sizes )
+      {
+        if ( maxWidth < size.width() ) maxWidth = size.width();
+        if ( maxHeight < size.height() ) maxHeight = size.height();
+      }
+      QSize maxSize(maxWidth, maxHeight);
+
+      // get and print legend
+      QImage legend = symbolIcon.pixmap(maxWidth, maxHeight).toImage();
+      if ( painter )
+      {
+        painter->drawImage( QRectF( point.x(), point.y(), mWmsLegendWidth, mWmsLegendHeight ), legend, QRectF( 0, 0, maxWidth, maxHeight ) );
+      }
+      symbolSize.rwidth() = mWmsLegendWidth;
+      symbolSize.rheight() = mWmsLegendHeight;
+    }
+    else
+    {
+      if ( painter )
+      {
+        painter->setBrush( rasterItem->color() );
+        painter->drawRect( QRectF( point.x(), point.y() + ( itemHeight - mSymbolHeight ) / 2, mSymbolWidth, mSymbolHeight ) );
+      }
+      symbolSize.rwidth() = mSymbolWidth;
+      symbolSize.rheight() = mSymbolHeight;
     }
-    symbolSize.rwidth() = mSymbolWidth;
-    symbolSize.rheight() = mSymbolHeight;
   }
   else //item with icon?
   {
@@ -555,6 +585,8 @@ bool QgsComposerLegend::writeXML( QDomElement& elem, QDomDocument & doc ) const
 
   composerLegendElem.setAttribute( "symbolWidth", QString::number( mSymbolWidth ) );
   composerLegendElem.setAttribute( "symbolHeight", QString::number( mSymbolHeight ) );
+  composerLegendElem.setAttribute( "wmsLegendWidth", QString::number( mWmsLegendWidth ) );
+  composerLegendElem.setAttribute( "wmsLegendHeight", QString::number( mWmsLegendHeight ) );
   composerLegendElem.setAttribute( "wrapChar", mWrapChar );
   composerLegendElem.setAttribute( "fontColor", mFontColor.name() );
 
@@ -622,6 +654,8 @@ bool QgsComposerLegend::readXML( const QDomElement& itemElem, const QDomDocument
 
   mSymbolWidth = itemElem.attribute( "symbolWidth", "7.0" ).toDouble();
   mSymbolHeight = itemElem.attribute( "symbolHeight", "14.0" ).toDouble();
+  mWmsLegendWidth = itemElem.attribute( "wmsLegendWidth", "50" ).toDouble();
+  mWmsLegendHeight = itemElem.attribute( "wmsLegendHeight", "25" ).toDouble();
 
   mWrapChar = itemElem.attribute( "wrapChar" );
 

src/core/composer/qgscomposerlegend.h

@@ -87,6 +87,12 @@ class CORE_EXPORT QgsComposerLegend : public QgsComposerItem
     double symbolHeight() const {return mSymbolHeight;}
     void setSymbolHeight( double h ) {mSymbolHeight = h;}
 
+    double wmsLegendWidth() const {return mWmsLegendWidth;}
+    void setWmsLegendWidth( double w ) {mWmsLegendWidth = w;}
+
+    double wmsLegendHeight() const {return mWmsLegendHeight;}
+    void setWmsLegendHeight( double h ) {mWmsLegendHeight = h;}
+
     void setWrapChar( const QString& t ) {mWrapChar = t;}
     QString wrapChar() const {return mWrapChar;}
 
@@ -139,6 +145,11 @@ class CORE_EXPORT QgsComposerLegend : public QgsComposerItem
     /**Height of symbol icon*/
     double mSymbolHeight;
 
+    /**Width of WMS legendGraphic pixmap*/
+    double mWmsLegendWidth;
+    /**Height of WMS legendGraphic pixmap*/
+    double mWmsLegendHeight;
+
     /** Spacing between lines when wrapped */
     double mlineSpacing;