[BACKPORT] to 1.8. Further improvements to multiple layer removal in one operation support for the registry and apply suggested improvements from Jürgen.

Author: timlinux

python/core/qgsmaplayerregistry.sip

@@ -26,6 +26,23 @@ public:
  //! Retrieve the mapLayers collection (mainly intended for use by projection)
  QMap<QString,QgsMapLayer*> & mapLayers();
 
+ /** Add a list of layers to the map of loaded layers
+    @returns QList<QgsMapLayer *> - a list of the map layers that were added
+    successfully. If a layer is invalid, or already exists in the registry,
+    it will not be part of the returned QList.
+    @note added in QGIS 1.8
+
+    As a side-effect QgsProject is made dirty.
+
+    If theEmitSignal is true (by default), a layersAdded( QList<QgsMapLayer *>)
+    signal will be emitted indicating that a batch of layers were added.
+    Not emitting signal is useful when you want to use registry for layers
+    on a different canvas and don't want them added to the main canvas automatically.
+ */
+ QList<QgsMapLayer *> addMapLayers( QList<QgsMapLayer *> theMapLayers,
+                                    bool theEmitSignal = true ) /Deprecated/;
+
+
  /** Add a layer to the map of loaded layers 
     @returns NULL if unable to add layer, otherwise pointer to newly added layer
     @note
@@ -38,17 +55,26 @@ public:
  */
  QgsMapLayer *  addMapLayer(QgsMapLayer * theMapLayer /Transfer/, bool theEmitSignal = TRUE);
 
- /** Remove a layer from qgis
+ /** Remove a set of layers from qgis
+    @note As a side-effect QgsProject is made dirty.
+    Any canvases using the affected layers will need to remove them
 
-    @note
+    If theEmitSignal is true (by default), a layersRemoved( QStringList theLayerIds )
+    signal will be emitted indicating to any listeners that the layers are being removed.
 
-    As a side-effect QgsProject is made dirty.
+    The layer being removed is deleted as well as the registry
+    table entry.
+ */
+ void removeMapLayers( QStringList theLayerIds, bool theEmitSignal = true );
 
+
+ /** Remove a layer from qgis
+    @note
+    As a side-effect QgsProject is made dirty.
     Any canvases using that layer will need to remove it
- 
     theEmitSignal - see addMapLayer()
  */
- void removeMapLayer(QString theLayerId, bool theEmitSignal = TRUE);
+ void removeMapLayer(QString theLayerId, bool theEmitSignal = TRUE) /Deprecated/;
 
  /** Remove all registered layers 
 
@@ -72,17 +98,26 @@ public:
  void reloadAllLayers();
 
 signals:
+ /** Emitted when one or more layers are removed from the registry
+    @note intended to replace layerWillBeRemoved in QGIS 1.8
+ */
+ void layersWillBeRemoved( QStringList theLayerIds );
 
-    /** emitted when a layer is removed from the registry
-
-       connected to main map canvas and overview map canvas remove()
-    */
+ /** emitted when a layer is removed from the registry
+     connected to main map canvas and overview map canvas remove()
+     @note rather use layersWillBeRemoved
+ */
  void layerWillBeRemoved(QString theLayerId);
 
-    /** emitted when a layer is added to the registry
+ /** Emitted when one or more layers are added to the registry
+    @note intended to replace layerWasAdded in QGIS 1.8
+ */
+ void layersAdded( QList<QgsMapLayer *> theMapLayers );
 
-       connected to main map canvas and overview map canvas addLayer()
-    */
+ /** emitted when a layer is added to the registry
+     connected to main map canvas and overview map canvas addLayer()
+     @note rather use layersWereAdded
+ */
  void layerWasAdded(QgsMapLayer * theMapLayer);
 
  /** emitted when ALL layers are removed at once

src/app/gps/qgsgpsinformationwidget.cpp

@@ -1073,13 +1073,17 @@ void QgsGPSInformationWidget::updateCloseFeatureButton( QgsMapLayer * lyr )
   {
     if ( mpLastLayer )  // disconnect previous layer
     {
-      disconnect( mpLastLayer, SIGNAL( editingStarted() ), this, SLOT( layerEditStateChanged() ) );
-      disconnect( mpLastLayer, SIGNAL( editingStopped() ), this, SLOT( layerEditStateChanged() ) );
+      disconnect( mpLastLayer, SIGNAL( editingStarted() ),
+                  this, SLOT( layerEditStateChanged() ) );
+      disconnect( mpLastLayer, SIGNAL( editingStopped() ),
+                  this, SLOT( layerEditStateChanged() ) );
     }
     if ( vlayer ) // connect new layer
     {
-      connect( vlayer, SIGNAL( editingStarted() ), this, SLOT( layerEditStateChanged() ) );
-      connect( vlayer, SIGNAL( editingStopped() ), this, SLOT( layerEditStateChanged() ) );
+      connect( vlayer, SIGNAL( editingStarted() ),
+               this, SLOT( layerEditStateChanged() ) );
+      connect( vlayer, SIGNAL( editingStopped() ),
+               this, SLOT( layerEditStateChanged() ) );
     }
     mpLastLayer = vlayer;
   }

src/app/legend/qgslegend.cpp

@@ -95,12 +95,14 @@ QgsLegend::QgsLegend( QgsMapCanvas *canvas, QWidget * parent, const char *name )
            this, SLOT( writeProject( QDomDocument & ) ) );
 
   // connect map layer registry signal to legend
-  connect( QgsMapLayerRegistry::instance(), SIGNAL( layerWillBeRemoved( QString ) ),
-           this, SLOT( removeLayer( QString ) ) );
+  connect( QgsMapLayerRegistry::instance(),
+           SIGNAL( layersWillBeRemoved( QStringList ) ),
+           this, SLOT( removeLayers( QStringList ) ) );
   connect( QgsMapLayerRegistry::instance(), SIGNAL( removedAll() ),
            this, SLOT( removeAll() ) );
-  connect( QgsMapLayerRegistry::instance(), SIGNAL( layerWasAdded( QgsMapLayer* ) ),
-           this, SLOT( addLayer( QgsMapLayer * ) ) );
+  connect( QgsMapLayerRegistry::instance(),
+           SIGNAL( layersAdded( QList<QgsMapLayer*> ) ),
+           this, SLOT( addLayers( QList<QgsMapLayer *> ) ) );
 
   connect( mMapCanvas, SIGNAL( layersChanged() ),
            this, SLOT( refreshCheckStates() ) );
@@ -279,38 +281,48 @@ void QgsLegend::removeGroup( int groupIndex )
   }
 }
 
-void QgsLegend::removeLayer( QString layerId )
+void QgsLegend::removeLayers( QStringList theLayers )
 {
   QgsDebugMsg( "Entering." );
-
-  bool invLayerRemoved = false;
-
-  for ( QTreeWidgetItem* theItem = firstItem(); theItem; theItem = nextItem( theItem ) )
+  foreach (const QString &myId, theLayers)
   {
-    QgsLegendItem *li = dynamic_cast<QgsLegendItem *>( theItem );
-    if ( li )
-    {
-      // save legend layer (parent of a legend layer file we're going to delete)
-      QgsLegendLayer* ll = qobject_cast<QgsLegendLayer *>( li );
+    bool invLayerRemoved = false;
 
-      if ( ll && ll->layer() && ll->layer()->id() == layerId )
+    for ( QTreeWidgetItem* theItem = firstItem();
+          theItem; theItem = nextItem( theItem ) )
+    {
+      QgsLegendItem *li = dynamic_cast<QgsLegendItem *>( theItem );
+      if ( li )
       {
-        if ( !ll->isVisible() )
+        // save legend layer (parent of a legend layer file we're going to delete)
+        QgsLegendLayer* ll = qobject_cast<QgsLegendLayer *>( li );
+
+        if ( ll && ll->layer() && ll->layer()->id() == myId )
         {
-          invLayerRemoved = true;
+          if ( !ll->isVisible() )
+          {
+            invLayerRemoved = true;
+          }
+          removeItem( ll );
+          delete ll;
+          break;
         }
-        removeItem( ll );
-        delete ll;
-        break;
       }
     }
+    emit itemRemoved();
+    if ( invLayerRemoved )
+      emit invisibleLayerRemoved();
   }
   updateMapCanvasLayerSet();
   adjustIconSize();
+}
 
-  emit itemRemoved();
-  if ( invLayerRemoved )
-    emit invisibleLayerRemoved();
+//deprecated delegates to removeLayers now
+void QgsLegend::removeLayer( QString theLayer )
+{
+  QStringList myList;
+  myList << theLayer;
+  removeLayers(myList);
 }
 
 void QgsLegend::mousePressEvent( QMouseEvent * e )
@@ -846,77 +858,98 @@ int QgsLegend::getItemPos( QTreeWidgetItem* item )
   return -1;
 }
 
-void QgsLegend::addLayer( QgsMapLayer * layer )
+//introduced in QGIS 1.8 - add layers in a batch
+void QgsLegend::addLayers( QList<QgsMapLayer *> theLayerList )
 {
   QgsDebugMsg( "Entering." );
   if ( !mMapCanvas || mMapCanvas->isDrawing() )
   {
     return;
   }
 
-  QgsLegendLayer* llayer = new QgsLegendLayer( layer );
-  if ( !QgsProject::instance()->layerIsEmbedded( layer->id() ).isEmpty() )
-  {
-    QFont itemFont;
-    itemFont.setItalic( true );
-    llayer->setFont( 0, itemFont );
-  }
+  QSettings settings;
 
-  //set the correct check states
-  blockSignals( true );
-  llayer->setCheckState( 0, llayer->isVisible() ? Qt::Checked : Qt::Unchecked );
-  blockSignals( false );
+  //Note if the canvas was previously blank so we can
+  //zoom to all layers at the end if neeeded
+  bool myFirstLayerFlag = false;
+  if ( layers().count() > 0 ) myFirstLayerFlag = true;
 
-  QgsLegendGroup *lg = dynamic_cast<QgsLegendGroup *>( currentItem() );
-  if ( !lg && currentItem() )
+  //iteratively add the layers to the canvas
+  for (int i = 0; i < theLayerList.size(); ++i)
   {
-    lg = dynamic_cast<QgsLegendGroup *>( currentItem()->parent() );
-  }
+    QgsMapLayer * layer = theLayerList.at(i);
+    QgsLegendLayer* llayer = new QgsLegendLayer( layer );
+    if ( !QgsProject::instance()->layerIsEmbedded( layer->id() ).isEmpty() )
+    {
+      QFont itemFont;
+      itemFont.setItalic( true );
+      llayer->setFont( 0, itemFont );
+    }
 
-  int index;
-  if ( lg )
-  {
-    index = lg->indexOfChild( currentItem() );
-  }
-  else
-  {
-    index = indexOfTopLevelItem( currentItem() );
-  }
+    //set the correct check states
+    blockSignals( true );
+    llayer->setCheckState( 0, llayer->isVisible() ? Qt::Checked : Qt::Unchecked );
+    blockSignals( false );
 
-  if ( index < 0 )
-  {
-    index = 0;
-  }
+    QgsLegendGroup *lg = dynamic_cast<QgsLegendGroup *>( currentItem() );
+    if ( !lg && currentItem() )
+    {
+      lg = dynamic_cast<QgsLegendGroup *>( currentItem()->parent() );
+    }
 
-  QSettings settings;
-  if ( lg && settings.value( "/qgis/addNewLayersToCurrentGroup", false ).toBool() )
-  {
-    lg->insertChild( index, llayer );
-  }
-  else
-  {
-    insertTopLevelItem( index, llayer );
-    setCurrentItem( llayer );
-  }
+    int index = 0;
+    if ( lg )
+    {
+      index = lg->indexOfChild( currentItem() );
+    }
+    else
+    {
+      index = indexOfTopLevelItem( currentItem() );
+    }
 
-  setItemExpanded( llayer, true );
-  //don't expand raster items by default, there could be too many
-  refreshLayerSymbology( layer->id(), layer->type() != QgsMapLayer::RasterLayer );
+    if ( index < 0 )
+    {
+      index = 0;
+    }
 
-  updateMapCanvasLayerSet();
+    if ( lg && settings.value( "/qgis/addNewLayersToCurrentGroup", false ).toBool() )
+    {
+      lg->insertChild( index, llayer );
+    }
+    else
+    {
+      insertTopLevelItem( index, llayer );
+      setCurrentItem( llayer );
+    }
+
+    setItemExpanded( llayer, true );
+    //don't expand raster items by default, there could be too many
+    refreshLayerSymbology( layer->id(), layer->type() != QgsMapLayer::RasterLayer );
 
+    updateMapCanvasLayerSet();
+    emit itemAdded( indexFromItem( llayer ) );
+}
   // first layer?
-  if ( layers().count() == 1 )
+  if ( myFirstLayerFlag )
   {
+    QgsMapLayer * myFirstLayer = theLayerList.at(0);
     if ( !mMapCanvas->mapRenderer()->hasCrsTransformEnabled() )
-      mMapCanvas->mapRenderer()->setDestinationCrs( layer->crs() );
+      mMapCanvas->mapRenderer()->setDestinationCrs( myFirstLayer->crs() );
     mMapCanvas->zoomToFullExtent();
     mMapCanvas->clearExtentHistory();
   }
   //make the QTreeWidget item up-to-date
   doItemsLayout();
 
-  emit itemAdded( indexFromItem( llayer ) );
+
+}
+
+//deprecated since 1.8 - delegates to addLayers
+void QgsLegend::addLayer( QgsMapLayer * layer )
+{
+  QList<QgsMapLayer *> myList;
+  myList << layer;
+  addLayers( myList );
 }
 
 void QgsLegend::setLayerVisible( QgsMapLayer * layer, bool visible )

src/app/legend/qgslegend.h

@@ -207,7 +207,13 @@ class QgsLegend : public QTreeWidget
 
   public slots:
 
-    /*!Adds a new layer group with the maplayer to the canvas*/
+
+    /*!Adds a new layer group with the maplayers to the canvas*/
+    void addLayers( QList<QgsMapLayer *> );
+
+    /** Adds a new layer group with the maplayer to the canvas
+      * @note Deprecated since 1.8 - use addLayers rather
+      */
     void addLayer( QgsMapLayer * layer );
 
     void setLayerVisible( QgsMapLayer * layer, bool visible );
@@ -264,8 +270,14 @@ class QgsLegend : public QTreeWidget
      */
     void removeGroup( int groupIndex );
 
+    /*!
+     * @deprecated - use removeLayers() rather
+     */
     void removeLayer( QString );
 
+    /** Remove one or more layers from the legend */
+    void removeLayers( QStringList theLayers );
+
     /** called to read legend settings from project */
     void readProject( const QDomDocument & );